Raw Water Pump Impeller Replacement How To Guide

Changing A Raw Water Pump Impeller

Changing an impeller is not a difficult chore, and it is one that every boater should consider adding to their arsenal of do-it-yourself maintenance techniques. It is common for many engines to have an impeller change that takes less than 20 minutes, even if you are a bit sluggish. The physical access to the pump is the most difficult component of the job to do. Raw water impellers are a common wear item; nevertheless, they do not always operate according to a set schedule of hours or days. The simplest of errors, such as forgetting to open the engine’s raw water intake, or the presence of a partial weed plug in the intake, may cause an impeller to fail in a matter of minutes.

If they are allowed to run hot for an extended period of time, they may lose a blade or drop a piece that may become lodged in a hose, elbow, or the heat exchanger.

It is critical to locate and replace all of the missing impeller parts in order to avoid further damage or overheating concerns.

Some people believe this is excessive, and you’ll have to determine for yourself what kind of maintenance routine you want to follow.

In our Westerbeke, I pay $16.00 for the impeller to be replaced, and the process takes around 8-10 minutes.

In comparison to the few minutes and few boat bucks necessary for this easy maintenance, an overheated engine or a thrown blade can cost many, many times more in terms of both time and money.

In the spring, or if you run the engine dry for more than 30 to 45 seconds, or when the flow is restricted due to an obstruction in the strainer or intake system, you should have a trouble-free impeller that will never throw a blade or cause flow to be restricted owing to a worn impeller again.

New Impeller Kit

This is the impeller kit that I’m now using in my engine. It comes with gaskets, installation instructions, and impeller lube, which is nothing more than glycerin in its purest form. If you look closely, you will note that the impeller box does not mention Westerbeke on it. On this specific engine, Westerbeke makes use of a Johnson pump, and Hamilton Marine carries the precise impeller item that is required. They could be useful for your engine as well. The impeller on the left is a fresh new replacement, whereas the impeller on the right was taken from the engine last autumn after it was winterized.

Yes, I could get this impeller via Westerbeke, but it would cost about $38.00 against $16.00 at Hamilton Marine, despite the fact that they are identical down to the engraved Johnson component number on the impeller itself.

I usually recommend that you have at least one entirely new replacement impeller on board at all times, as well as a minimum of two gaskets on hand. Sometimes you’ll need to inspect the impeller, but it may not be necessary to replace it, necessitating the use of an additional gasket or o-ring.

Removing The Screws

As previously said, this job is quite simple. It is possible to change an impeller if you are capable of changing oil, air filters, or cleaning a blender after creating frozen chick drinks in a blender. Loosen and remove the screws, starting with Step 1. If they are frozen or corroded, use some PB Blaster to defrost them, but be extremely cautious not to blast them all over the place. PB Blaster like eating pump seals, engine seals, and even engine gaskets for breakfast, so please keep that in mind.

Purchase a few extra face plate screws to keep on hand in case one of them happens to fall into the bilge.

Pry The Plate Off

Step 2: Remove the cover plate by prying it off. This is something I do with a knife blade and it works well. There are several methods for removing the plate, but whichever method you use, make sure it does not damage the gasket’s mating surfaces in the process. Before you begin, be sure you CLOSE THE ENGINE INTAKE SEACOCK before pulling off the plate or attempting to remove the impeller. This is critical. You shouldn’t be surprised if water starts to drain after you remove the cover plate. There will be some water left in the HX and hoses after this.

Check For Wear

In addition to the face plate of a water pump, it is regarded a wear item. Alternatively, if it is scored and worn, it should be replaced or flipped. Just in case, I have a spare cover plate that is brand new on board. Even at Westerbeke’s excessive costs, it was just $13.00, making it a very affordable piece of insurance once again. Pumps with cover plates that do not have component numbers stamped on them, such as certain Oberdorfer versions, are among them. Alternatively, if your cover plate is worn and the opposite side does not have any paint or stamping marks, you may just turn it over and re-use the plate.

My paper gasket came out in one piece, with the exception of a little fragment of paper stuck to it.

You can get lucky every now and again!

Clean The Cover Plate

When it comes to water pumps, their face plates are considered worn items. Replacement or flipping it is recommended if it has been scored and worn down to a pulp. Always have an extra cover plate on hand in case something goes wrong with the first one. Even at Westerbeke’s outrageous costs, it was just $13.00, making it a very affordable kind of insurance once again. Pumps with cover plates that do not have component numbers stamped onto them, such as certain Oberdorfer versions, are available.

It is not possible to flip my Westerbeke face plate since it has a component number imprinted on it. I was able to remove my paper gasket in one piece, with the exception of a little fragment. That was not done on purpose, but rather by chance. You can get lucky every now and again.

Ready To Re-Install

As soon as I finished cleaning this plate, I made the decision to replace it with my new one and save this one as a backup. Even though the plate in the photo shows just minor wear and could probably be re-used with success, I chose to purchase a new one for $13.00 to save money.

The Old Impeller

The fact that I changed this impeller only a couple of months ago in April and that it is now late July indicates that you have been reading and paying attention to what I have been writing. So what is it about this impeller that has already broken and damaged it? That is a straightforward response. On a spring tide day, we were cruising back in complete silence with no breeze. It is a lovely aspect of spring tides in Maine that they reach out far up onto the shoreline and draw every last piece of seaweed and dumped debris back off the beach and back into the water.

1. Water temperature was closely monitored, and it only rose to around 8-10 degrees over usual when we arrived to the mooring.
2. It was undoubtedly reducing flow, but it had not been completely depleted; it had just been pumping less volume.
3. Every time I find myself in a scenario like this, when the flow was restricted, I make it a point to examine the impeller.
4. Normally, I would have stopped the boat and cleaned the strainer, but the temperature was not even at 190 degrees, when it should have been at 180, and we had a hungry infant on board, so I continued to press forward.
5. If it’s in good shape, the only thing you’ll have to pay is a $.88 cent gasket.
6. Probably another 5-10 hours before this one started tossing chunks at me, if I’m being honest with myself.
7. Despite the fact that I believe the concept is excellent, I am a little wary after having had two previous attempts fail.
8. The use of Globe impellers may be an alternative, but I am aware of the failures I have witnessed and the fact that they are nearly two to three times the cost of my standard Johnson impeller.

Remove The Impeller

Whilst the basic principle of water pumps is the same across all manufacturers, there may be differences in the way the impeller is mounted on or linked to the shaft. This pump has a slotted shaft, and the impeller is attached to the shaft by a screw that fits into the groove. I just use my needle nose Vise Grip pliers to remove it from the situation. It just jumps out at you, and it couldn’t be any more straightforward. Some pumps are held together using set screws or c-clips. A set of c-clip pliers will be required for impellers that have retaining rings that are secured by c-clips.

Most engine and pump manufacturers include on-line parts guides that include an exploded picture of the engine or pump and allow you to have a peek inside the engine or pump before you open it up.

Check The Pump Body

Check the pump body for wear and debris, and replace the pump if necessary. Run your finger around the interior of the container to feel for grooves or rough patches, and then take a close look at it from all angles. Once you have completed this, add some impeller lube, also known as glycerin, to your finger and lubricate the interior surfaces of the pump body, including the rear wall, which is also a sealing surface for the impeller. Before final assembly or installation of the impeller, lubricate the back of the pump and the cover plate with glycerin to prevent sticking or corrosion.

The impeller material and some petroleum greases are incompatible with each other, and greases have a tendency to get sticky in the internals.

At any drug shop, it will cost you around $3.00 for a lifetime supply.

New Impeller

To prepare the impeller for installation, lubricate the whole exterior with glycerin. Using your fingers, push the lubricant into the pump body and seat it into the pump. Although I’ve seen it suggested that zip ties be used to pre-compress the impeller before insertion, I’m not sure I understand why this would be necessary. The impellers of extremely huge Detroit diesels, Cummins, Caterpillars, and even one lung teeny small Yanmars have all been changed, and they all went back in well without the need of a zip tie to pre-compress the impeller before reinstalling it.

• Do not be concerned if the vanes on your impeller were pointing in different directions when you removed it, as seen in the photo of the previous impeller.
• Occasionally, during the last revolution, the engine will actually spin back a notch or two, causing the impeller blades to be out of sync with respect to the rotational direction of the engine.
• It is a complete urban myth/dock lore that impeller vanes must be mounted in the direction of rotation in order to function properly.
• Please don’t be too hard on yourself about the direction of the vane; it just doesn’t matter.

Chose The Right Gasket

If you purchase an OEM impeller straight from Yanmar, Westerbeke, or Universal, to mention a few manufacturers, the impeller will almost always come with the appropriate gasket.

Select the proper gasket for your impeller if it comes with more than one, by comparing it to the cover plate or o-ring groove on the cover plate.

Prep The Gasket

These low-cost paper gaskets have a tendency to suck donkey balls. (grin) HondaBond 4 is a sealant that I occasionally apply to assist the gasket in forming a good seal (do not confuse HondaBond 4 with HondaBond HT which is silicone). As a general rule, I do not recommend silicone gasket maker for this application and instead recommend products such as the Hondabond 4, YamaBond, or ThreeBond 1104. Permatex also makes a product called The Right Stuff, which is quite comparable. These sealants do not completely cure, they stay flexible, and they will not contaminate the sealing surfaces with silicone after they have been applied.

• You simply need enough to cover the surfaces with a thin layer of skim coat.
• This helps to keep the gasket aligned and makes the technique a one-step operation.
• Depending on your skill level with a wrench, you may be able to do this by feel, but if not, a torque wrench may be necessary to complete the task.
• These paper gaskets are also susceptible to drying out.

Check Your Hoses

When you’re in the engine compartment, make a habit of checking your hoses physically and visually every time you’re there. This is a wire-reinforced hose that was on the verge of breaking down completely. Undoubtedly the most difficult to replace, and the only way I could tell it was damaged was by feeling its resistance. Corrosion and rotting of internal reinforcing wire through the jacket are evident by the white residue and bulges, which indicate significant corrosion and rotting.

All Done

As you can see, replacing an impeller is fairly simple! Best of luck and safe boating!

Impeller Replacement 101

A essential component of your engine’s cooling system, the impeller is a critical component of the cooling system. A spare impeller on board is a good idea in case of an unexpected failure of the primary one. Raw water pumps of the flexible impeller type are commonly seen in inboard and sterndrive engines. Flexible impeller pumps are commonly found in a variety of applications, including shower drain sump pumps, certain bilge pumps, wakeboard ballast pump systems, oil changing systems, and many others.

Why Impeller Pumps Fail

Pumps with flexible impellers perform best when they are used on a regular basis. If your pump is electrically operated and has been sitting for months with the impeller in one position and the blades on one side bent, it may “take a set” and trip a circuit breaker when it is turned on. When the pump is turned on, it is possible that the impeller will become stuck to the housing and fall apart. Impellers are harmed by debris that is sucked into the machine, by chemicals, and, most importantly, by running out of fuel.

Of course, each time you start the engine, you should inspect the wet exhaust on your transom to ensure that the correct flow of cooling water is being provided.

Correctly built impellers can endure for several years, but you should adhere to a preventative maintenance routine rather than relying on emergency repairs when possible.

Regardless, an impeller will ultimately break while in operation, and this will most likely occur at an inopportune moment for the user. Because the impeller is one of the most important components of your engine’s cooling system, you should always have a spare on board.

Selecting the Right Impeller

Our inventory includes impellers from a variety of brands, including Johnson Pump, Mercury Marine, Sierra, and Jabsco, among others. There are a variety of methods for determining the West Marine model number for a new Jabsco impeller, including the following:

• Manufacturers such as Johnson Pump, Mercury Marine, Sierra and Jabsco are among those who supply us with impellers for our customers. When looking for a new Jabsco impeller, there are numerous methods to use to obtain the West Marine model number.

Neoprene, Nitrile or Polyurethane

Use neoprene impellers for engine cooling as well as for fresh and salt water transfer chores, if possible. Neoprene is only suited for use in pumps when only trace quantities of oil or diesel fuel are present, such as in a car wash. Nitrile impellers should be used for bilge pumping and transfer responsibilities when the water is significantly polluted, such as when it is contaminated by oil or fuel. To transport diesel fuel, a sliding vane pump such as the Jabsco Vane Puppy or the Groco Flo-Master should be utilized.

This application makes use of impellers made of polyurethane.

Replacing Impellers in Raw Water Pumps

The process of replacement is pretty straightforward. In order to use a raw water pump, you must first shut the water intake through the hull valve. After that, unscrew the screws holding the pump’s end cover in place and remove the cover and gasket. Remove the old impeller by grasping the impeller’s hub with channel lock or needle-nose pliers and pulling it out. Use an Impeller Puller Tool for the quickest and most straightforward removal (or in cases when the other tools are ineffective). It is not recommended to use a screwdriver to lever it out, since this may score the soft bronze of the pump body, resulting in leaks and other problems.

• When the impeller has been removed, it should be thoroughly examined.
• By bending each vane, you can make sure it’s working properly.
• Small bits of rubber can migrate into the heat exchanger or the engine, causing overheated damage and premature failure.
• Condensing the impeller’s vanes using a hefty rubber band or a loop of light line, then inserting and pulling the loop out with your pliers is the best method.
• Your pump may require further maintenance, particularly if the seals, bearings, wear plates, or clutch are worn out or damaged.

As a general reference book, we strongly suggest this one. If your pump has reached the end of its useful life, most of the “classic” pumps from Jabsco, Sherwood, and Johnson Pump are still available for purchase.

Raw Water Pump Impeller replacement – How to Guide

1. I spent some time attempting to determine how difficult it would be to replace the Impeller, but was unable to locate any information on the actual step-by-step procedures for doing so. In order to help those who are new to do it yourself maintenance, I decided to put this information out there for those who would rather spend a weekend bonding with their boat than spend $200 dollars only to have the impeller rebuilt. This is a collection of the instructions from the Solec handbook, as well as some shortcuts I discovered while completing the work myself. Following are the operating instructions for the Mercruise 5.0L MPI engines with serial numbers 6000XX and above. 5L MPI SRN6000XX raw water impeller is being replaced with a new one. 1. Loosen the serpentine belt as much as possible. Using a 5/8 box wrench and a 5/16 socket, unscrew the 5/8 locking nut on the starboard side of the engine so that the belt tension is released and you may remove the belt from the raw water pump, alternator, and tension pulley. Take a look at Fig. 12. The next step is to remove all of the water from the engine. If you’re towing your boat or putting it on blocks, now would be a good time to remove the drain plug from the boat
2. Otherwise, there will be a lot of water in the bilge. A little wrench may be used to start the first drian plug which is located at the bottom of the engine, on the port side (if you can’t get it to spin, use a small screwdriver). The following two are located on the inlet and outlet of the Raw Water pump, respectively. You may wish to remove the water/fuel separator filter at this stage if you want to have easier access to the engine. Make certain that all of the water has been drained from the raw water pump
3. Otherwise, when you go to remove the hoses, you will be battling against the vacuum formed by the water in the pump, which will be difficult. The placements of the drain plugs are depicted in Fig. 2. The hose shown in Figure 2 is the one that is used to drain the water and connects to the three-way splitter that is located directly above the water pump and adjacent to the alternator once it has been emptied. Disconnect it right now if you want. This will make it much easier to remove the entire assembly. 4. It is now necessary to rectify all of the mercrusier diagrams available on the internet. Take a look at figure 3. In the diagram, take notice of the double headed screw15 and the nut16. They are depicted in the erroneous place
4. Instead, they should be depicted at the location where screw17 and washer20 are depicted. It is really Screw17 that is in the lower hole, not the top one. In addition to securing the raw water pump component in place, these screws and nuts also serve to secure one end of a bracket for the starboard side tension puller in place. It is likely that you will require a Swivel/U join socket adaptor in order to get the clearance necessary to break them free. Once these are released, the entire bracket should come tumbling down
5. However, you will not be able to remove it at this time. Fig. 35. Graphite on a white background with a black outline. After that, you’ll need to unscrew the nut that holds the starboard side tension pulley mounting bracket, which is located below the alternator. Take note of Fig. 4. It will be possible to move the tension pulley and its mounting bracket out of the way once this has been completed. Fig. 46. Fig. 46. The next step is the most difficult. The raw water pump’s intake and exhaust hoses should be unclamped, and the hole assembly should be taken out as a result of this. Take a look at Fig. 57. The raw water pump should now be removed from its mounting bracket now that you have gotten yourself out of the bilge. Only a 10mm socket/wrench should be required to remove the two bolts from the rear of the pump and the one screw that is located on top of the pump. After that, unscrew the four remaining bolts on the rear of the pump and pull the pump out from behind it. Take a look at Fig. 68. If you want to make this process as simple as possible, you’ll need a specific tool at this point. If you have an impeller puller, use it to remove the impeller (as seen in figure 7) from the case
6. If you don’t, go to your local boaters world and get one. Keep track of the rotation angle of the impeller that you removed since the replacement impeller will need to be installed in the same manner. Illustration 79. A small amount of soapy water will aid in the installation of the impeller in the casing. Then, using the replacement O-ring that came with the impeller kit, replace the O-ring on the case and reassemble the raw water case as instructed. The raw water pump’s bolts, as well as the bolts connecting the raw water pump to the mounting bracket, should be tightened to 8.8ft-in. Install the intake and exhaust water hoses to the raw water pump again, making sure to tighten the hose clamps and drain plugs all the way. 11.Tighten the bolts holding the raw water pump and starboard tension pulley mounting frame to the engine block to 30 ft-lb of force. 12.Re-attach the engine hose that goes under the raw water pump to the vehicle. tighten the tension pulley mounting bolts located under the alternator. Repair the serpentine belt and tension it so that it bends no more than 1/4 inch at its widest span between pulleys, then tighten it again. 15. Drop the boat in the water or put on the muffs and monitor the PSI and/or temperature of the water. As a result of the engine being emptied, the water pressure will be quite low at first, but it should return to normal within a few seconds. It took me two full days to complete this task on my first attempt, which included the time it took to acquire the necessary materials. along with determining the best method of accessing particular areas I estimate that I could complete this task in roughly 30 minutes the next time. According to my calculations, even after purchasing the impeller kit, the impeller puller, and a torque wrench, it will still be less expensive than having the dealer perform the work. My only expenditure will be $34.00 for the kit the next time, which is a significant savings over the $200+ I spent the previous time. I hope you find this content interesting

Four SunsNot a pot stirrerTECHNICAL Contributor PLATINUM Sponsor

• This is a fantastic piece of writing! Personally, I feel that maintaining the engine’s cooling system in peak operating condition is the most important and difficult aspect of boat maintenance. I’ve seen individuals talk about changing the oil every 50 hours, but they don’t bother to look at the impellers, strainers, and risers. Thank you for your hard work. Gary, I want to conduct a series of these as I aim to perform the most of my own servicing in order to lower my operating costs as much as possible. Aside from that, it will provide me with a comprehensive inventory of the tools and components I should take on board in case I break down while out on the sea.

• It’s a well-written piece. When my pump failed last year, the temperature was a steamy 95 degrees. I made the decision to get it done by a local auto repair. Can you tell me how much space you guys have to go to this pump? As you can see in the picture, there is very little place for me to get my arms in there
• Wish2fish
• The lack of space is the reason for writing this message. There actually isn’t any clearance between the water separator and the engine mounting bracket, despite the fact that most instruction sets I’ve found urge you to approach it from the side. Neither a waste holding tank nor a generator would be out of place on my boat, which is located downstream of the engine. Moreover, in front of the engine, there is a space of around 1 to 2 feet between it and the gas tank and freshwater tank, which are piled on top of each other. Even worse, I only have approximately 6 inches to work with from the front of the water pump to get to the bolt that holds the mounting bracket for the water pump. This is why I require a Swivel/U-joint for my socket set
• I need to be able to come out and then angle up or to the side in order to have the necessary leverage. In order to properly replace the impeller, it is recommended that you start from the front and remove all of the blet, mounting brackets, and hoses. This will give you enough room to remove the raw water pump and its hoses from the bilge in order to do the impeller repair. If you’d like, I can take a picture of the engine room the next time I’m on the boat if that may be of use

GunnWell-Known MemberTECHNICAL Contributor

• You have written an excellent piece. Last year, when my pump failed, the temperature was a steamy 95°F. I made the decision to have it done by a local auto repair shop. Can you tell me how much space you’ve got to get to the pump? Wish2fish
• The lack of space in which I can get my arms is the reason for writing this article
• Wish2fish
• The lack of space is the reason for writing this post There actually isn’t any clearance between the water separator and the engine mounting bracket, despite the fact that most instruction sets I’ve found tell you to approach it from one side. In the wake of the engine on my boat, there is adequate space for either a waste holding tank or a generator. There are around 1 to 2 feet between the front of the engine and the gas tank and freshwater tank, which are piled on top of each other in the area in front of the engine. Even worse, I only have approximately 6 inches of clearance from the front of the water pump to reach the bolt that holds the mounting bracket for the water pump in place. As a result, I want a Swivel/U-joint for my socket set, so that I may come out of the socket and then angle up or to the side in order to provide the necessary leverage. In order to properly replace the impeller, it is recommended that you start from the front and remove all of the blet, mounting brackets, and hoses. This will give you enough room to remove the raw water pump and its hoses from the bilge in order to do the impeller replacement properly. In the event that you require it, I can take a picture of the engine room the next time I’m on the boat if that will be of use

Dave SWell-Known MemberTECHNICAL Contributor

• Excellent piece of writing.: thumbsup: The brass water pumps on the newer 350 MAGs, such as the one I have on my boat, replace the plastic ones found on the older models. It seems likely that I will be doing my for the first time in the next 6-12 months. According to the current information, it will be essential to loosen the gasoline cooler on the 350 MAG engines in order to have enough area to get to the pump. Furthermore, because the pump is different, there may be some other things that need to be done a little differently as well
• Dave
• The raw water pump on my vehicle was not made of plastic, but rather of what appeared to be cast iron, and unlike the diagram in Fig 3 (which was taken from one of the service manuals available on the internet), it did not have anything on the back of the pump other than the intake and exhaust hose fittings. As a result, our configuration may be more similar than not.

• My water pump bearings failed after only two years and 200 hours of operation. The recommended length of service is three years or 300 hours. I don’t believe that changing the impeller is a good idea. I replaced the complete pump, particularly because the bearings had failed. I’ve started carrying an extra pump. I’ve used raw water pumps from Jabsco on my boats for years and have never experienced anything like this. In comparison, these merc pumps are total and utter crap. In addition, the information in the preceding thread is correct regarding pump/impeller replacement. Another example of bad design is the fact that in order to service the impeller, you must remove the belt and the complete pump. What a load of nonsense. Moreover, despite the fact that I had complete warranties, the raw water pumps were not protected. Is there anyone else having troubles with their raw water pump? Tom. You did an excellent job with the writing. Consider mentioning that this is a Bravo water pump configuration and that it does not applicable to Alpha setups. I had intended to document the full alpha procedure this year and post it on this site as well
• How much does the raw water pump for the 350 Mags cost? Barry
• I believe that the most perplexing aspect of this entire topic of impellers is that this is nothing more than a water pump in its most basic form (in my mind). Consider what would happen if we had to pay as much attention to, and put as much effort into, the water pumps in our automobiles as we do with these engines. Can you picture needing to replace the water pump on your automobile on a regular basis if it was a newer model? Of course, they aren’t comparing apples to apples, but geeze, don’t you think they could come up with something a little more dependable? I agree that the merc water pump design is bad. The level of serviceability and durability for such a critical component is simply unacceptable, and it is absolutely not on pace with many other brands. When purchased from a dealer, they cost around $325.00
• However, they are presently available on eBay for $130.00 shipped with pully. I just purchased a spar because none were available when I experienced my failure.

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• It took only two years and 200 hours for my water pump bearings to fail. Three years or 300 hours of servicing is recommended. I don’t think it’s a good idea to change the impeller
• I replaced the complete pump, especially because the bearings were damaged. My extra pump is now always with me. In all of my years of boating, I have never experienced this type of failure with the Jabsco raw water pumps. If you look at them side by side, these Mercedes pumps are utter and total junk. In addition, the information in the preceding thread is correct regarding pump/impeller replacements. Another example of bad design is the fact that in order to service the impeller, you must remove the belt and the complete pump assembly. What a slap in the face to our intelligence. Moreover, despite the fact that I had complete warranties, the raw water pumps were not protected. Have any of you experienced troubles with your raw water pump? Tom. Wonderful write-up, congratulations. This is a Bravo water pump configuration, and it does not apply to Alpha setups, which you may wish to highlight. I had intended to document the full alpha procedure this year and post it on this site as well
• How much does the raw water pump for the 350 Mags cost?
• Barry
• This is nothing more than a water pump, which is what I find most perplexing about the entire topic of impellers (in my mind). Consider what it would be like if we had to pay as much attention to, and put as much effort into, the water pumps in our automobiles as we do these engines. Imagine having to replace the water pump on your automobile on a regular basis if it were a newer model. Of course, they aren’t comparing apples to apples, but geeze, don’t you think they could come up with something a little more dependable? I agree that the merc water pump design is a disaster. There is something really wrong with the serviceability and durability of such a critical component. It definitely falls short of many other brands in this category. When purchased from a dealer, they cost around $325.00
• However, they can be purchased on eBay for $130.00 shipped with pully. I just purchased a spar, since none were available when I experienced my failure
• Nonetheless,

• Amen. For a little moment, I thought you were going to agree with their choice of colors. I think that comparing it to an automobile water pump is unfair
• Yet,

ronddsWell-Known Member

• 3rd of October, 2006 Jersey Shore2001 380DAM 380DAM 380DAM erc 8.1s erc 8.1s erc 8.1s (2008). V-drives from Hurth ZF 63. GMR 24xHD dome, WB 7.0 BCGD (2013), Garmin 8208740 MFDs, WB 7.0 BCGD (2013) Your raw water pump does not have an equivalent in the vehicle industry. Instead of using sea water to cool the coolant, automobiles use air to do it. Boats, like automobiles, are equipped with a circulator pump. and they need little maintenance – or, to put it another way, they don’t require care more than every 2-3 seasons. Also worth noting is that Crusader now employs a stainless impeller for raw water collection, and they are not nearly as temperamental as our mercs were in previous years. I didn’t see the stage in those instructions where it says to “use a shrink ray to reduce oneself down to the size necessary to fit between the engines and the bulkhead.” As for the step that reads “have your chiropractor on speed dial,” I didn’t see it since I was focused on getting to the bolts and hose clamps while dangling upside down in the engine compartment for over two hours. This job is ridiculously simple, provided that you have easy access to the pump removal area. EVERYTHING RELATES TO ACCESS
• Again, I recognize that these are not the same as a comparison
• However, my observation is nothing short of astounding at how the industry appears to believe that it is “OK” to have a (somewhat critical engine component such as this) fail after a relatively short period of time. It appears to me to be technically outdated

NehalenniaWell-Known Member

• 22nd of August, 2007 310DA Marysville, Washington 20011 Westerbeke is equipped with twin 350 MAGs. 4.5KWTwin 350 MAG V-drives with variable speed control Because they require $200 from each and every one of us on a regular basis
• THANK YOU for starting this discussion. The time it would have taken me to figure this out and then redo it after making mistakes would have been several days or perhaps weeks. My first time around, I was able to complete my port engine in about an hour, with the majority of the time being spent on the hoses. I’d want to share some of the things I’ve learnt about this. With the exception of the Fuel-Water filter, I didn’t have to remove anything else. It was only a matter of removing the three bracket nuts and the hose clamps. (I did not remove the mounting bracket for the tension pulley on the starboard side.) It was difficult to get the two primary hoses disconnected (even with the water drained). For any hose removal, there are two things that can be done to make the job easier: 1) carefully use a flat head screwdriver to break the seal around the edge of the hose
• And 2) twist the hose until you feel it come loose (this was hard on the two big hoses). Even with these suggestions, it was still difficult. I cracked a couple knuckles while removing the hoses. But first, buy yourself a set of these, which are Flex ratchet Wrenches that can be found at Lowe’s, Sears, Advanced Auto, and other hardware stores, among other places. Depending on the brand you choose, you may get only the 10mm one for $12 or the entire set for $60. They are really helpful in obtaining some of these bolts. off. In addition, I placed Silicon grease on the O-ring to seal it. This may be obtained at a diving shop or by placing an online order. It aids in the creation of a good seal and maintains the O-Ring flexible, allowing it to maintain a good seal. After a few years, petroleum-based compounds (such as Vaseline, grease, and so on) will cause the O-ring to become goo.

NehalenniaWell-Known Member

1. 22nd of August, 2007 Westerbeke, WA2001 310DA twin 350 MAGs, Marysville, WA2001 4.5KWTwin 350 MAG V-drives with variable speed control Tom. The photos on the link have become inactive. That being said, I’d be interested in taking another look at this.

Sidebar should be visible.

Changing A Raw Water Pump Impeller by Compass Marine How To

23-JUL-2008 The Raw Water Pump is a device that pumps raw water into a system. Changing an impeller is not a difficult chore, and it is one that every boater should consider adding to their arsenal of do-it-yourself maintenance techniques. On many engines, changing the impeller takes less than 20 minutes, even if you are a sluggish worker who works in a confined space. The access to the pump is the most difficult component of the process. Impellers are a wear item, although they do not always adhere to a “time” or “hours of usage” schedule, as is the case with other wear items.

• Both being drained and being exposed to high temperatures are unwelcome to them.
• If this occurs, you will have a much greater job on your hands in terms of locating the piece in order to avoid more damage or overheating concerns from occurring.
• Some people believe that this is excessive, and you will have to determine for yourself what your maintenance regimen will be.
• When I change the impeller in my Westerbeke diesel engine, I pay $16.00 for the part and it takes approximately 8-10 minutes.
• When an engine gets too hot or a blade breaks, the cost in both time and money is far more than the few minutes and “few” boat dollars that are necessary for this easy maintenance.

The result should be a trouble-free impeller that will never throw a blade or cause a flow loss due to a worn impeller if you do it every spring, or every time the engine is run dry for more than 30-45 seconds, or when the engine is operating under restricted flow because of a blockage in the strainer or intake system 23-JUL-2008New Impeller Kit is now available.

• Gaskets, instructions, and impeller lubrication (which is nothing more than glycerin) are all included with the purchase of this unit.
• On this specific engine, Westerbeke makes use of a Johnson pump, and Hamilton Marine carries the precise replacement kit that is required.
• The impeller on the left is a fresh new replacement, whereas the impeller on the right was taken from the engine last autumn after it was winterized.
• Yes, I could get this impeller via Westerbeke, but it would cost about $38.00 against $16.00 at Hamilton Marine, despite the fact that they are identical down to the engraved component number on the impeller’s surface.
• 23-JUL-2008Removing the ScrewsAs I already stated, this job is really simple.
• To defrost them or rust them, spray them with PB Blaster, but be extremely careful not to spray it on too thickly!
• Use a penetrating oil only if absolutely necessary.

Make sure you have some spare face plate screws on hand because one will always fall into the bilge, never to be seen again, and it will always do so at the most inconvenient of times.

23-JUL-2008 Remove the plate by prying it off.

This is accomplished with the help of my Leatehrman knife blade, which is satisfactory.

It goes without saying that you should CLOSE the engine intake seacock before pulling off the plate or replacing the impeller for obvious reasons.

23-JUL-2008 Examine for signs of wear The face plate of a water pump might be regarded to be another wear-and-tear component.

Just in case, I have a spare cover plate that is brand new on board.

Pumps with face plates that do not have partnumbers “stamped” on them, such as certain Oberdorfer versions, are among those to be avoided.

My Westerbeke face plate has a deep embossed design and cannot be flipped over for cleaning.

That was not done on purpose, but rather by chance.

Clean the cover plate on the 23rd of July, 2008.

I just use Scotch-Brite pads to accomplish this.

Keeping up with your cleaning tasks can help to reduce the likelihood of a gasket leak occurring.

As soon as I finished cleaning this plate, I made the decision to replace it with my new one and save this one as a backup.

The Old Impeller on the 23rd of July, 2008.

So what is it about this impeller that has already broken and damaged it?

On a spring tide day, we were cruising back in complete silence with no breeze.

About a mile from our mooring, I noticed a shift in the exhaust noise, as if less water was being thrown out of the exhaust pipe.

The next day, I returned to the boat and cleaned the strainer as well as the intake hose that runs between the strainer and the seacock.

Clearly, it was sufficient to heat up the impeller and cause damage to it.

I was somewhat aback by the fact that only a few minutes of reduced flow could do such significant damage.

The bottom line is as follows: At the very least, if you run your impeller dry or with reduced flow, you should check on it.

If it’s broken, like mine was, get a new one.

I was right!

Despite the fact that I believe the concept is excellent, I am a little wary after having had two previous attempts fail.

23-JUL-2008 Remove the impeller from the engine.

This pump has a slotted shaft, and the impeller is attached to the shaft by a screw that fits into the groove.

It just jumps out at you, and it couldn’t be any more straightforward.

A set of c-clip pliers will be required for impellers that have retaining rings that are secured by c-clips.

Most engine and pump manufacturers include on-line parts guides that include an exploded picture of the engine or pump and allow you to have a peek inside the engine or pump before you open it up.

Run your finger around the interior of the container to feel for grooves or rough patches, and then take a close look at it from all angles.

Before final assembly or installation of the impeller, lubricate the back of the pump as well as the cover plate on the impeller side.

Avoid the use of petroleum-based lubricants since they have the potential to reduce the life of the impellers’ composite material.

Although I’ve seen it suggested that zip ties be used to pre-compress the impeller before insertion, I’m not sure I understand why this would be necessary.

It is not necessary to overthink the re-insertion; simply carry out the procedure.

This is rather common and is caused by the small amount of “back spin” that a diesel engine might experience as it shuts down.

Even if you placed it in entirely backwards in relation to the pump’s rotation, it would self-correct without causing any long-term problems.

23-JUL-2008 Selecting the Proper Gasket If you purchase an OEM impeller straight from Yanmar, Westerbeke, or Universal, to mention a few manufacturers, the impeller will almost always come with the appropriate gasket.

If your impeller arrived with more than one gasket, choose the most appropriate one by comparing it to the cover plate or o-ring groove on your cover plate.

eOceanic

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The trick to inserting a new water pump impeller

Pumps with flexible rubber impellers are the most popular type of cooling mechanism for sailboat engines. The rubber impeller, on the other hand, wears out and degrades with time, necessitating its replacement on a regular basis, often once a year. This can be problematic, particularly for bigger pumps, where the vanes can be uncomfortably stiff and the pump housing can be difficult to access in the confines of an engine compartment, as well as for smaller pumps.

Why address this?

A faulty impeller might cause the engine to overheat. Making impeller maintenance a less difficult process increases the likelihood that it will be completed. Having a seamless implementation might make the process of replacing a failing impeller while at sea more pleasant.

How to address this?

When replacing an impeller, the majority of the time the difficulty is with the new replacement impeller’s stiff blades being difficult to install into the impeller housing. The use of a cable tie at this point, in order to precompress the blades and lower the diameter of the replacement impeller, should make insertion of the new impeller far easier. Simply follow the instructions outlined below:

• 1. Use a clean cloth to thoroughly wipe out the impeller housing, and then apply a generous layer of petroleum jelly to the whole surface (Vaseline). If petroleum jelly is not available, a generous amount of dishwashing soap will suffice
• If none of these options is available, a generous amount of petroleum jelly will suffice. 2. Apply petroleum jelly to the impeller that has been replaced. This not only assists in easing the impellor into the pump, but it also serves as initial lubrication because the pump will not be completely submerged in water during initial starting. 3. Tie an electrical cable tie around the impeller
• 4. Tighten the cable tie down until it brings the impeller vanes together into a contracted form, but not so tightly that it is difficult to remove
• 5. 5. Insert the constrained impeller into the pump housing
• 6. As the impeller slides into position, the cable tie will come into contact with the outside edge of the housing. Pull the cable tie off using pliers if necessary while pushing the impeller into the pump housing, allowing the vanes inside the pump housing to be released. When the cable tie is removed, the impeller will cheerfully return to its original position. 7. Replace the cover with a new one. Some are shaped in such a way that the orientation is immediately apparent. However, if you happen to have a perfectly round cover that isn’t immediately apparent, search for any lettering or marking on the cover. The text will generally be shown with the right side up, indicating how it is oriented. In the event that this is not possible, you should be able to see the shadowing of the camera on the cover and determine its direction
• In a cross-orientation, tighten the cover in the same manner as you would a car’s steering wheel. As the screws are tightened into the bronze housing, be patient with them
• They should be just snug enough. The material is not very strong and it is simple to strip out the threads by overtightening it. Moreover, as soon as the engine starts, the impeller vanes will automatically move into the right position, eliminating the need to try to match the original alignment.

A cable tie is used to restrict the movement of the impeller. Photograph courtesy of Michael Harpur Getting the impeller into the machine is frequently the most difficult element of the process. It is possible, however, that you will have problems removing the original impeller. Using a pair of pliers to free a stuck impeller is the most effective method of removing it. Take a hold of a vane from either side with both pliers and pull it out from below. When removing the impeller from the housing, it is critical not to pry the tools away from the edge of the housing.

Any damage to the edge may result in an insufficient seal, which may result in air intrusion or a leak.

With thanks to:

Yacht Obsession is a film by Michael Harpur. Replacement of the impeller on a Volvo Penta marine water pump A picture is worth a thousand words, as the saying goes. We are constantly on the lookout for images that capture the essence of this encounter in a bright, sunny setting. If you have any photographs that you think we might be able to utilize, please post them here. All we want is a brief explanation of the image if it is not immediately evident how you would like to be attributed for your work and how you would like to be credited for your work.

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How to: change a marine diesel water impeller

According to Bruce Jacobs of Rubicon 3, a well maintained impeller pump should prevent an impeller failure. When you start your engine, one of the most important things to look for is whether or not the raw water cooling system is functioning correctly. It should be possible to see water pouring out of the exhaust pipe. The water and exhaust gases will have traveled from the engine to the skin fitting through a strengthened rubbing hose that has been routed through several water traps and loops.

If you don’t see any exhaust water, you’ll need to look for the raw water impeller by following the line that comes out of the raw water filter.

Removal

Then, carefully remove the faceplate screws, being careful not to lose them in the bilge. Before you begin, place a tray or tea towel on the floor and make sure you are using the proper instrument to avoid damaging them. When the faceplate is removed, a little amount of water will drip out; have a sponge ready to clean up the mess.

Impeller

When removing the impeller, it is recommended practice to use an impeller puller, which pulls the impeller out from under the housing, preventing damage to the housing from occurring. In practice, many individuals use a set of fine-nose pliers, which are not perfect, but are enough as long as you are cautious to pull straight. Look for cracks and wear during a thorough inspection of the item.

Missing bits

Inspect the rubber impeller for signs of damage or wear on the blades before continuing. If any parts are missing, it is critical to ensure that these do not become caught in the cooling system, since this can prevent effective cooling from occurring. Examine the water system and take apart the hoses and heat exchanger to look for broken pieces. Because there is some delicate copper tubing in the heat exchanger, use soft electrical wire to gently push out any rubber that you may come across.

Corrosion

You could also run into wear or corrosion in the pump’s housing, face plate, or lift plate – the cam that causes the splines to bend, resulting in the lift effect of the pump. This is held in place by grub screws and may be easily changed. You should also inspect the rubber O-ring seal for the faceplate (some engines use paper gaskets), and while you’re at it, check the drive shaft seal located at the rear of the housing — a leak here may cause catastrophic damage to an engine.

Fitting

1. New impellers are often packaged with a small amount of oil or lubrication. Take care to put it in the correct way around – it has a front and a rear – and to bend the fins in the direction that the engine will turn – generally towards the engine side and away from the sea-water entrance – before sliding it into place. Replace the face plate after applying a little amount of lubricant to the O-ring or gasket. You may be able to reuse the old gasket if it’s in good shape if it’s an emergency situation and you don’t have access to a spare gasket. Other options include applying sealants to the interior of the face plate, but this should only be done for the purpose of getting you home
2. It is best practice to replace your impeller before it fails. As long as you start the engine with all of the correct tests – raw water seacock open, filter clean and water streaming out of the exhaust – you should not have any problems with the engine. Take a look at the impeller’s packaging to see how many service hours are suggested, and make sure you replace it before it breaks.

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The professionals at rubicon3adventure.com, the UK’s specialists in adventure sailing and training, have provided this information with gratitude.