Is this pump rebuildable?

Feb 10, 2004
3,919
Hunter 40.5 Warwick, RI
This is a water pump that was installed on a Volvo MD22L-B. The seal was leaking water, and since I have a groove on the shaft where the seal rides, I could not simply replace the seal. But now I am looking at this pump contemplating a rebuild that will include new bearings, seal, and of course a new impeller and gasket. The cam looks to be in good condition although I will remove it and look at it very closely.

The pump body is my primary concern. The walls are smooth but the inside surface has a partial circular groove in the area of the cam. This groove can be seen in the picture below and can be felt with a fingernail. I attempted to measure the depth with my vernier caliper but the readings varied and I have no confidence in the readings. However, the largest reading I saw was 0.004" and the least reading was 0.0015". The groove is arguably very shallow. If you click on this image it will become full size and the groove will be very easy to see.
2015_1122_1428081280x960.jpg

There are similar grooves in the cover plate, but I can sand them out with fine sandpaper on a piece of glass.

As for the groove on the shaft at the seal location- Volvo very nicely does not offer a replacement shaft, so I am stuck with buying a complete pump for $500 or so. I plan to install a SKF Speedy sleeve on the shaft to provide a smooth sealing surface.

This will be a pump that I will carry as a spare.

So my question is- Is the groove in the pump body acceptable? I realize that there could be some pumping efficiency lost due to water leaking in that groove, but I suspect it would not even be measurable, so I feel that is not a reason to discard the body.
 
Sep 15, 2009
6,243
S2 9.2a Fairhope Al
is that pump made by volvo i suspect it's not and it looks a lot like a johnson pump to me you may try doing research on johnson pumps and may find something that will cross over
 
Jan 25, 2011
2,391
S2 11.0A Anacortes, WA
Sorta looks like a Johnson F7B9. The cover plate should tell. If so, look at spxflow.com
 
Jan 27, 2008
3,045
ODay 35 Beaufort, NC
Rich, you could fix the shaft by grinding it down, chrome plating and then grinding back to original size. Likewise if the groove you are talking about in the body is in the face in front of the cam, you could bore the body a little deeper to clean up the grove and then bond in a bronze washer the thickness that you removed to get it back to the original depth. You'll need a machine shop to do this unless you have access to one. See if a local community college with a machining program would take it on as a project to teach the kids how to do repairs. Or maybe for a small donation they'd let you use the equipment during off hours.
 
Nov 26, 2012
1,653
Hunter 34 Berkeley
The groove is gonna cause it to not develop a good seal. May work anyway but not as well. Maybe rebuild it, test it and keep it as an emergency spare if it works.
 
Aug 28, 2015
190
Oday 28 St Joseph, MI
The bronze from which those pumps are made is really tough material but all pumps wear from the passing of the vanes on their surfaces hundreds of thousands of times. And unless you boat in distilled, filtered water, there is microscopic grit in the water and this all adds up to the pump eventually putting out less than it should. Add the wear on the cover plate and the back of the inside and, well, you get the picture. I would bite the bullet and replace it.
 
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Likes: JoeWhite
Jun 2, 2011
347
Hunter H33 Port Credit Harbour, ON.
The groove is probably insignificant in as much as the impeller will bridge the groove on the flat side surface. The majority of the surface appears to be good. A pump becomes inefficient when there is a groove that bridges the intake and output sections. The pump is delivering large flow and relatively low pressure. I think that you would not notice any issues.
 
Feb 10, 2004
3,919
Hunter 40.5 Warwick, RI
Thanks for all the input. I have decided to rebuild the pump with new bearings and a seal. I am also going to install a SKF Speedi-Sleeve on the shaft to cover the worn spot where the seal rides. Use of a Speedi-Sleeve is a well known and accepted practice for all kinds of machinery. Since Volvo won't sell a shaft by itself, the only choice is to use the sleeve or junk the $500 pump.
Since I replaced the pump because it was leaking seawater past the seal and the worn spot on the shaft, the Speedi-Sleeve should fix that issue. I didn't replace the pump because it wasn't pumping enough water, so I really don't think that the worn grove in the bottom of the pump cavity will affect the flow in any measurable amount.
There are some pumps that are designed with a wear plate in the bottom of the pump chamber that can re replaced like the cover plate can be replaced. Unfortunately, this pump isn't designed that way.
 
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Likes: Rick D
Jan 30, 2012
1,123
Nor'Sea 27 "Kiwanda" Portland/ Anacortes
Rich

What is the smallest Speedi Sleeve? If not small enough you can make a brand new duplicate shaft My price for a 10mm shaft was about $65

Charles
 
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Feb 14, 2014
7,400
Hunter 430 Waveland, MS
So my question is- Is the groove in the pump body acceptable? I realize that there could be some pumping efficiency lost due to water leaking in that groove, but I suspect it would not even be measurable, so I feel that is not a reason to discard the body.
It should be expectable. Would guess that the groove is where the impeller vane is at maximum deflection or maximum force. Since rubber pump vanes are the seal against both the cam and the cover plate/back housing, your impeller wear pattern should reveal if there is a problem.

Careful on your cover plate polish, your tolerance is that gasket thickness (onion paper).:yikes: I have the same engine as yours.

I stopped or perhaps delayed my slight drip ( i mean very very slight) by tapping the shaft seal gently around the seal toward the engine to reposition it. I believe the shaft is tapered. Is it?

Keep us/me informed of the progress.
Jim...

PS: My VP22L-B has ≈1400 hours.
 
Feb 14, 2014
7,400
Hunter 430 Waveland, MS
You got my curiosity up. You can replace the shaft by a new replacement number (almost as expensive as the rebuild kit). My guess it was an improvement over the first production ( which wore to fast ;)). Please note that damn expensive O-Ring (part #4) and part #8 is your water seal:banghead:. I would guess shaft wear was from bearings. In my post #12, it was part #8 that I tapped.

http://www.marinepartseurope.com/en/volvo-penta-explodedview-7746710-26-2812.aspx

BTW the cam part#9 is replaceable too. It looks like the bearings have to be pressed on the shaft.
Jim...

PS: Keep your pump housing.
 
Feb 10, 2004
3,919
Hunter 40.5 Warwick, RI
I have finished my rebuild of the Volvo raw water pump #3580946 or the latest number 3582510. I soaked and cleaned all the parts in an ultrasonic cleaner (probably over-kill) and then using wire brushes in my dremel and by hand I cleaned up all of the important surfaces. I used a small bench press to install the new bearings- industry number 6003-2RS. These are standard clearance tolerance bearings- they easily meet the requirements of the pump. I could not source the seal (Jabsco SP2700-1027) locally so I ordered a couple of them from Depco in Florida. Now I have a spare since the pump uses just one seal.
I should have taken pictures as I went along, but I didn't - sorry. I used a small bench press to install the bearings on the shaft. Each bearing presses up to a shoulder on the shaft so there was no special positioning required. Next I installed the SKF Speedi-Sleeve on the shaft to cover the worn groove from the water seal. The Speedi-Sleeve is supplied with an installation tool that slides over the sleeve and is used to drive it onto the shaft into the correct position. The instructions tell you to put a thin coating of a non-hardening sealer on the inside of the sleeve, and I think that is to fill the worn groove and help to support the sleeve in that spot. I used Permatex 2B sealer. The lip on the sleeve needs to be removed after the installation in order for the shaft and sleeve to fit into the pump. This lip needs to be cut in one spot prior to installation. It's very important to do this because otherwise the lip is much more difficult to remove afterwards.
The shaft and bearing assembly is now inserted into the pump body. It is not a press fit, but it is close. Very light taps seat it properly and then the internal C-clip is installed to hold the bearings and shaft in place. I coated the bearings and the internal pump body with 3-in-1 oil before insertion.
The o-ring is now slid onto the shaft and positioned in the middle of the weep holes. I think the purpose of this o-ring is just to fling off any water that gets past a failed seal so that the water doesn't get to the bearings. Finally the seal is lubricated and installed. I slipped a corner of a plastic bag over the splines to protect the seal lip from any possible damage from the splines. I used a deep socket that was almost the diameter of the seal and would accept the shaft to install it.
The cover plate was wire-brushed and then lapped on a piece of glass with 150 and 400 grit sandpaper to smooth out the wear grooves. It is not perfect, but I am confident that it will work just fine.
I will not install an impeller until I am ready to use the pump. This will be my spare unit that I will carry on-board. From the attached picture looking into the pump body, you can see the edge of the Speedi-Sleeve in position with the water seal.
 

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Sep 15, 2009
6,243
S2 9.2a Fairhope Al
wow did you do all that in a vacuum controlled environment ....you were really thorough in that process...nice to see someone take so much effort good job
 
Nov 6, 2006
9,885
Hunter 34 Mandeville Louisiana
Great looking job, Rich.. Ya have a spare that you can really depend on now.
 
Feb 14, 2014
7,400
Hunter 430 Waveland, MS
The o-ring is now slid onto the shaft and positioned in the middle of the weep holes. I think the purpose of this o-ring is just to fling off any water that gets past a failed seal so that the water doesn't get to the bearings.
Great work!:clap: I am making lottsa notes about the shaft sleeve.

The following section is not meant to over shadow your craftsmanship, but to help you on what to look for as to wear on you new pump.
-------------------
The rotating water seal (part #8) is pressure sealed against the rotating rubber impeller (part #10) and would not be expected to wear. The impeller is, in effect, a rotating rubber O-ring.

The O-Ring (part #4), which is a compression type stationary seal, seals the rotating water seal (part #8) against the rotating part of the shaft bearings (part#6) (inside race). Thus the rotating water seal (part #8) is sandwiched sealed between the o-ring and the impeller.

If you get a drip on the new pump, you should only need to buy parts 4, 8 , & 10 for a full seal for the bearings, but normally just 10 the impeller.

WaterPump.png


BTW I am curious of your engine hours and would you sell me your spare for say...$150 :biggrin: if mine leaks like yours did?
Jim...
 
Oct 2, 2008
3,807
Pearson/ 530 Strafford, NH
So back to those grooves, I noticed the grooves on my pump cover and decided to go with a Speed Seal. So what makes the groove? I just check and the vanes stand a little proud of the impeller body for some purpose. I would think a little water would cool the pump body. What's the thinking of the pump engineers? Will these grooves come back?

All U Get
 
Feb 10, 2004
3,919
Hunter 40.5 Warwick, RI
Not being a pump engineer ( my engineering education was electrical - Snap, crackle, pop, and Ka-Zap...), I think that the grooves that wear in the cover plate and in the bottom of the pump cavity are due to sand and other abrasive particles in the water that get caught between the metal and the impeller. I don't know how to eliminate that wear, but unless the grooves are really deep, I can't understand how they would noticeably affect the pumping capacity. I read that others have maintained that the plate needs to be perfectly smooth for their pump to work. I'm not saying they are wrong, but that is not my experience.
 
Feb 10, 2004
3,919
Hunter 40.5 Warwick, RI
The rotating water seal (part #8) is pressure sealed against the rotating rubber impeller (part #10) and would not be expected to wear. The impeller is, in effect, a rotating rubber O-ring.

The O-Ring (part #4), which is a compression type stationary seal, seals the rotating water seal (part #8) against the rotating part of the shaft bearings (part#6) (inside race). Thus the rotating water seal (part #8) is sandwiched sealed between the o-ring and the impeller.

If you get a drip on the new pump, you should only need to buy parts 4, 8 , & 10 for a full seal for the bearings, but normally just 10 the impeller.

BTW I am curious of your engine hours and would you sell me your spare for say...$150 :biggrin: if mine leaks like yours did?
Jim...
Your pump may be slightly different than mine, but on my pump the water seal (#8) is pressed into a machined cavity before the impeller is installed. The seal is slightly below the inside surface of the pump cavity so it doesn't ride on the impeller. The o-ring (#4) does not press against the water seal because the body clearance toward the bearings is a greater diameter than the o-ring - so the o-ring cannot be compressed between the body and the water seal. Looking at my replacement Volvo pump that is presently on my engine, the o-ring is centered on the shaft under the weep holes. So the o-ring doesn't seal anything- that is why I think it's purpose is to fling water if there was a seal failure ( like I had due to the wear groove in the shaft.