I've pulled my Sherwood G65 pump off my Perkins 4108 for a rebuild. At the drive end there's been some deformation as you can see from the picture. It seems as if the drive shaft on the motor side didn't fully sit inside the pump shaft. Can any one explain this? I have the manual, but am having a hard time finding any diagrams for the adapter plate and all the corresponding assembly for the motor side of the pump drive.
Thanks in advance!
The 4 studs that mount the pump are part of a round plate inside the timing gear cover. That plate floats, so during mounting you can center it and the pump and drive slot.
You need to measure the depth the drives overlap. It wouldn't be the first time someone put a damaged part back in. I have a number of parts and shop manuals covering many years. None show the timing cover/raw water pump assembly in any detail. Price for a new pump is about $350. Parts are available. These pumps can be rebuilt as long as the housing isn't damaged.
Two pix of pump parts.
Depco: Depco Pump Company
Marineparts: PERKINS COOLING PUMPS
The image in the above picture isn't like it is, that's some other thing. The mounting ring with the studs needs to be tighened down with the pump in the center. The shaft you have is bent because the pump was not in the center of the pump drive gear. To do it corectly you need to double check the alignment at 90deg.
With all the old gasket gunk removed and a new gasket in place and more goop, slide the pump into place with no interference. Turn the engine 180deg (90deg at the pump). and check the fit again.
I'm not personally familiar with your engine, never having worked on one, and there may be model variations specific to it, but there may be a 'coupling' missing from your shaft. The specified shaft for a G65 pump is 12444, a picture of it is shown below.
The pump flange should seal against the engine mounting flange with a new gasket and clean flanges with no additional sealant, though with less than perfect surfaces you might need some.
DEPCO pump is right in the next town down south of me I have used them for over 25 years.They just do pumps , they know pumps. Big ones small ones,.any pump repair and they stand behing there stuff 100%.
Depco pump Clearwater fl !
I uses a blue Globe impeller in my Perkins 4108 water pump. The only impeller i will use.
A couple of dollars more but less wear and no tear off of rubber fingers ever. ! and i carry spares
I've pulled my Sherwood G65 pump off my Perkins 4108 for a rebuild. At the drive end there's been some deformation as you can see from the picture. It seems as if the drive shaft on the motor side didn't fully sit inside the pump shaft. Can any one explain this? I have the manual, but am having a hard time finding any diagrams for the adapter plate and all the corresponding assembly for the motor side of the pump drive.
Thanks in advance!
When I left Corfu for Italy in 2007 my salt water pump on my 4108 gave up and I made it to Orthoni by pouring salt water into the cooling (by the bucket load).
The next day we sailed back to North Corfu and managed to get the pump to a workshop in Corfu Town old port. ( Known in those days the "Rolls Royce Man") The next day it was rebuilt and off we went to Italy.
When you live on an island they "FIX" things. Pity the world in not like that any more. Our dish washer pump bearing packed in here in the UK. The only answer was to buy a new pump, it almost the cost of a new dish washer. In Corfu they would have fixed it!
I'm sure a good machine shop can sort it.
I can't see anyone really answer his concern?
Obviously the pump had been done up tight or oil would have been spewing out everywhere.
I'd have to think a bearing behind the pump drive has worn or collapsed to allow it to move away from the pump shaft.
Would it be possible to use long nose pliers to grab the drive and see if there is any in/out slack in the drive?
Quite possible you might need to replace that pump drive if it's worn similar to the pump shaft.
The 4 studs that mount the pump are part of a round plate inside the timing gear cover. That plate floats, so during mounting you can center it and the pump and drive slot.
Guy, you are correct. I've done this repair/change out several times. When you read the manual closely, it says to loosely install the pump, (I put the new pump on, using silicon rubber to seal, and I make it snug enough to hold it in place, but loose enough that with force, the inner ring will slide a little bit to align the shafts' axis). Then, roll the engine a few turns. This will align the axis of the pump shaft with the engine's internal driving shaft, (cam shaft?). I then tighten up the pump, carefully, in that position. I am a US Merchant Marine Chief Engineer. In my career I've worked on a lot of equipment that needs to be finessed, but never Diesel engines, until this. Usually Diesels are very precise; but this is English. Aligning teeth or pumps appears to be an issue in England. Perkins 4-108's/Westerbeke 40-108's are great/reliable engines. You just have to understand their quirks.
The alignment procedure outlined above is to align the seawater pump adaptor (drive) plate, which bolts onto the drive gear with three bolts and holds the drive key that actually drives the pump. See picture below.
It is clearly stated in the manual that that procedure should only be used if the adaptor plate has been loosened or removed and the alignment tool is unavailable, and is considered an interim method until the proper tool can be obtained. See page M4 in the manual linked to below.
Is should also be noted that the 4108 uses Sherwood, Johnson and Jabsco pumps and the drives on all three are about 7/8" in diameter, the same as the key that drives them.
The shaft that Monty shows in his original post, is clearly missing the 'coupling' (which looks to be hardened steel in the picture) that increases the size of the shaft to match the larger dimension of the drive key. This is likely the cause of the wear observed in the picture, but if someone has loosened the drive plate and not realigned it properly, that could be the end cause of the observed wear, and indeed, could have caused the 'coupling' to break, (in which case the two halves are lying in the oil pan or bottom of the gear housing), but the root cause is the reduced drive area caused by the loss of the coupling...
Coupling is #2 below (12442, not available separately).
And finally, again, sealant is not required on gasketed joints, unless the surfaces are badly corroded, pitted or scarred. Granted, there are, in rare cases, 'problem' joints that have to be 'sealed', but by far the cause of gasket leaks is improper or inadequate cleaning (a side effect of gluing gaskets on if not specifically specified) and distortion induced in flanges caused by overzealous tightening, oftentimes enough so that the mating flanges have to be dressed down with a flat file to re-obtain proper sealing surfaces.
The alignment procedure outlined above is to align the seawater pump adaptor (drive) plate, which bolts onto the drive gear with three bolts and holds the drive key that actually drives the pump. See picture below.
It is clearly stated in the manual that that procedure should only be used if the adaptor plate has been loosened or removed and the alignment tool is unavailable, and is considered an interim method until the proper tool can be obtained. See page M4 in the manual linked to below.
Is should also be noted that the 4108 uses Sherwood, Johnson and Jabsco pumps and the drives on all three are about 7/8" in diameter, the same as the key that drives them.
The shaft that Monty shows in his original post, is clearly missing the 'coupling' (which looks to be hardened steel in the picture) that increases the size of the shaft to match the larger dimension of the drive key. This is likely the cause of the wear observed in the picture, but if someone has loosened the drive plate and not realigned it properly, that could be the end cause of the observed wear, and indeed, could have caused the 'coupling' to break, (in which case the two halves are lying in the oil pan or bottom of the gear housing), but the root cause is the reduced drive area caused by the loss of the coupling...
Coupling is #2 below (12442, not available separately).
And finally, again, sealant is not required on gasketed joints, unless the surfaces are badly corroded, pitted or scarred. Granted, there are, in rare cases, 'problem' joints that have to be 'sealed', but by far the cause of gasket leaks is improper or inadequate cleaning (a side effect of gluing gaskets on if not specifically specified) and distortion induced in flanges caused by overzealous tightening, oftentimes enough so that the mating flanges have to be dressed down with a flat file to re-obtain proper sealing surfaces.
My engine is a Westerbeke 40-108, and therefore, perhaps somewhat different? In the photo the 4 studs that hold the pump to the engine penetrate the rigid cover and actually screw into a circular, "free floating", steel ring that is inside the cover. The holes in the cover are somewhat larger than the studs, and therefore do not properly center the pump. As I recall, the instructions recommended using plastigage or similar to check the depth of the penetration of the two shafts at the coupling; then use the proper number of gaskets, as shims, or none, to maintain that depth. I used silicon, and no gasket, because that is what was needed to obtain the proper clearance.
I am not near the boat or manuals, and quite busy at the moment, so I'm working from memory here. When I have time I'll read up on the tool that you mention. And yes, his pump shaft does appear to be missing the collar that would add strength to the coupling. That, combined with being off-axis would certainly cause the stated damage.
I am having problems and needs some advice. Perkins 4.108 has what appears to be the Jabscowaterpump. It has been leaking for years now. I need to replace it. The issue is it is very inaccessible. The front of the engine sits close to a bulkhead. I have tried to remove the 4 - 7/16 inch nuts that are securing the pump to the adapter plate. I do not think it is going to happen. I can not even get an open ended wrench on most of them. They also appear badly corroded. The pump seems to be attached to what I think is called an adapter plate. I found a photo that looks similar to my setup. You see the secondary ring behind the actual pump body. This ring has 4 bolts that I was able to get out. I put a good deal of pressure on the pump, wiggled it a bit but it remains rock solid.
Can anyone tell me if this pump can be removed with those 4 bolts out? I don't want to reef on it without knowing. or are the bolts that go through the body of the pump still holding it on? I have read some of the other posts on this and there is also an issue of alignment. Apparently if I take this adapter plate off it has to (should have) have a tool to center it when I put it on. Can anyone confirm I can get the pump off by removing the adapter plate and that I should get this tool to reinstall? Photo of similar setup to mine and tool inserted in adapter plate.