Water pump question

[Hydro Therapy]

Im in the process of replacing the impeller in my Westerbeke 12C two. The faceplate faces toward the rear of the engine so It’s another hideous job. I managed two remove the faceplate. Once off I managed to stick my phone camera and take a photo so I could see what I was dealing with. One of the impeller vanes was broken off so definitely time to service. I managed to blindly remove the old impeller with long pliers that have a 90 degree bend at the end. I was unable to install the new impeller. Too difficult to line up without seeing. I figured it would be best to remove the entire pump. The base of the pump is secured to the block by four stud bolts. I noticed there is a gasket between the pump base and block. Does the gasket keep fluid from coming out of the block? I want to know what I’m getting into before I remove it. I have a parts booklet and Westerbeke doesn’t list a gasket.

Thanks,

Mark

 

[Hydro Therapy]

The picture in my parts booklet shows an object that extends into the block from the impeller. I’m guessing the object butts up to the crank and the crank motion is what powers the pump? If correct will oil leak out when I remove the pump from the block?

 

[Jim 5757]

You have crankcase oil on the engine side. New gasket there would be best. Not knowing which brand pump I can only guess you might have a pump shaft with a woodruff key under the impeller,and a tongue on the engine side.

 

[Stu Jackson]

Mark,

Yes, you need a gasket between the pump body and the engine. Oil will not come out, because with the engine off the oil is in the sump at the bottom of the engine. What pump do you have? That will help us to help you. Can you post the picture(s) you took?

 

[Hydro Therapy]

I don’t know the pump brand but I attached a few pics. The one is of the old impeller before removed. The second is the pump but it’s not a great shot. Thanks for your response. I will hopefully make it back to the boat tomorrow and pull it.

 

[SG]

I'd not be pulling that pump off it were me....Have you considered Speedseal? We have had these for many years.

http://speedseal.com/speedseal.html

 

[Hydro Therapy]

The speed seal would be great if I was able to view or had straight access to the front of my pump. The problem is my access is from behind the pump. I’m unable to view the inside of it. Everything I do is by feel not by sight.

 

[Hydro Therapy]

I removed the water pump today. Stu was correct, no oil leakage from the block. Once I had it off I was able to view the pumps inside. Everything is in good condition. Since the removal allowed me to see the inside I realized why I couldn’t get the new impeller to seat. The through bolt on the new impeller was thicker then the one Iremoved. It was too thick to slide into the shaft. I should of noticed that prior to removing the pump but I didn’t. I still think it was a good idea to remove the entire pump. Now I now that pumps interior is in good shape.

I swapped the through bolts on the old and new impeller and installed. I just ordered a replacement gasket for the pump mount.

Thanks

 

[kmacdonald]

With the pump out it is easy to check the bearings. With the impeller removed, turn the pump shaft. It should be real smooth and no play in it. If there is, replace the bearings and seals.

 

[Ron20324]

I removed the water pump today.,,,...

Take pictures, for future reference, of the pump and gasket.

 

[KD3PC]

still time to do the speedseal...it will save you tons of time over the next few seasons in changing the impeller.
now while the whole unit is out.

 

[SG]

The impeller for our Westerbeke generator had a problem. The impeller’s stud inexplicably was too thick.

Not all of the replacements ARES consistent.

We had to simply get replacements or file down the stud.

I found this out after hours I’d tryung to figure it out. My mechanic figured it out in about twenty minutes of puzzling over it.

 

[kmacdonald]

The impeller for our Westerbeke generator had a problem. The impeller’s stud inexplicably was too thick.

Not all of the replacements ARES consistent.

We had to simply get replacements or file down the stud.

I found this out after hours I’d tryung to figure it out. My mechanic figured it out in about twenty minutes of puzzling over it.

Let's see, twenty minutes at $2.00/minute equals $40. Not bad. How much did you save on the impeller?

 

[SG]

The impellers were in Westerbeke boxes :^)))) The changed the spec slightly on some of their impellers.

Our mechanic replaced the "spars" with ones that fit - number was the same on the boxes. He said, "just one of those things."

I had messed around trying to figure-out why that damn impeller wouldn't slide in the generator. The generator was "hot", my knuckles were bloody, I just couldn't figure-out why I couldn't slide that sucker in there.

Anyway, if it doesn't fit, don't force it. (I was pretty close to pounding the damn thing in with a rubber mallet :^))) Of course that would have cost me a lot more than $40 ;^))))))

 

[kmacdonald]

I'd be really mad with Westerbeke. I wonder if it was an imitation product? Makes you wonder about their QC.

 

[SG]

Spooled again apparently found the same problem!!! See the quote below.

The 7 KW generator is a 1998 or '97 item. The water pump is really made by someone else. I'm not sure what the deal is. I have three or four extra generator impellers for the Chesapeake nettles and southern New England eel grass. Generally (that keeps the eel grass away ;^))) ) -- nothing keeps the nettles away in July and August except heading north to New England.

Anyway, I'm stocked with my spar impellers that all will fit like they're supposed to.
The through bolt on the new impeller was thicker then the one I removed. It was too thick to slide into the shaft. I should of noticed that prior to removing the pump but I didn’t. I still think it was a good idea to remove the entire pump. Now I now that pumps interior is in good shape.

 

[kmacdonald]

Yes, they all switch pump manufacturers from time to time. Wherever they get the best deal or they get mad when the pumps become available with a different part number at a 80% discount.
Getting the correct size key in an impeller shouldn't be rocket science. But then again, to design an exhaust system that when it fails, it will ruin the engine isn't engineering proficiency. Actually, I don't think an engineer would do it if they weren't required to but that's just my opinion.