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Raw water pump cover inspection

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bobct

Advanced Contributor
I replaced the impeller on one

I replaced the impeller on one engine and the inside of the cover has a slight groove.

Does this cause an issue which can make the engine run hot? I thought I read that here recently...


Bob
 
"Should not be a problem. As l

"Should not be a problem. As long as the impeller is in good shape, the groove is not overly deep, I'm pretty sure the groove will not interfere with volume/mass of water going through the pump."
 
"I have not seen a wear limit

"I have not seen a wear limit spec on the cover. Grooves and wear will affect the amount of bypass water in the chamber (bad) and worse case, could affect the ability to actually prime an air filled pump. From the OP report, i'd reuse the cover, but check the bearing for wear by looking at the slop of the shaft. All in all, the cover is the easiest item to replace, if the water volume is too low."
 
"Bob,

I replace an impeller

"Bob,

I replace an impeller a few weeks ago and had the exact same groove, an arc about 220 degrees in coverage and the deepest part of the groove in the middle of the arc maybe almost 90 degrees. I took the cover and rolled it around some wet 320 & 400 grit paper on the flat top of my table saw. In about 2 minutes, all of it was gone except for a slight shadow of the 90 degree arc which I left alone, re-installed and all was fine. I did not have any freeplay to speak of in the end cap or shaft bearing...so."
 
"Here is it
<[img]"http://www

"Here is it
334271.jpg
e35 cover"">As I think about it...It is in the area where the cam plate squishes the vanes down and probably creates extra pressure on the housing cover as they expand causing all of them to do this????"
 
"I use the 'see=ok, feel=w

"I use the 'see=ok, feel=work' approach on mine.
If you can see the groove but not have it catch your fingernail it is ok. If your nail catches when dragged across the scratch, it too deep.

Any opening that the cavities see is an exit path for the water or entry path for the air. The bigger they are, the larger the problem they present."
 
"your theory Al?

I don'

"your theory Al?

I don't think the grooving is caused by the pump's design, with the cam. I think it is caused by a foreign object (sand, etc) that gets inhaled during operation.

With the spinning impeller, the centrifugal force pushes all the looses 'parts' to the outer diameter of the housing. I'd suspect the cam forcing the vanes down, on exhaust, work those parts to the outer edges and the grooving results.

I've seen 'hard parts' embed into the impeller and groove housings as well as cams. It doesn't take much grit at 3000 rpm to groove that bronze (soft) material."
 
Does anyone know if the Sherwo

Does anyone know if the Sherwood E-35 pump cover is available as a seperate part? I see it in the "major rebuild" kit but not anywhere else.

The bearings and shaft are nice and tight so I'll just replace both covers if I can get them reasonably priced.
 
"The cover is not in the major

"The cover is not in the major rebuild kit, only the cover carbon bushing.
THe cover is just under $60 @ jms. comes with the new bushing."
 
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