Raw Water Impeller Shaft Lube

[Pgitug]

What kind of lube do you use on the shaft when you install a new raw water pump impeller? I have been told that petroleum based products are not recommended as they will deteriorate the rubber impeller.
What product works the best?

 

[Simi 60]

https://www.woolworths.com.au/shop/...nts-lubricant-gold?googleshop=1&cmpid=smaf014

And for end cap o rings

 

[DavidM]

Lanocote

 

[jleonard]

I use Pam cooking spray if the impeller does not include the lubricant.
I have also used liquid dish soap.

 

[psneeld]

I had a pretty serious water drip from my raw water pump on my genset several months back.

The bolts holding it on were pretty rusted from lack of maintenance from the PO, so I have been hesitant to do anything till my sumner break of major maintenance.

I sprayed the drip opening several times with Armor All Protectorant, and after 50 hours of running time, the genset still pumps great and doesnt leak anymore....so add another lubricant to the pile that works fine.

After a long spell of not running the genny, water is the only lube so just about any lube but dry is probably OK.

 

[Simi 60]

Lanocote

Just be wary, I used lanolin grease for the o rings on heat exchanger end cap last service.
Had a hell of a time removing it a few days as the stuff had set.
Had to scrape it off before reinstall

 

[Bacchus]

Won't harm rubber - and works on shafts - keep some in your tool kit

 

[smitty477]

Superlube synthetic - and also for "O" ring deck fills like fuel.
Waterproof and will not affect rubber - handy for door rollers and similar applications as well.

 

[Comodave]

+1 on the Superlube.

 

[dwhatty]

From Tony Athens:

"When installing a new impeller, throw out all that crap about lubing – Use any common white lithium grease (or similar grease) and life becomes easy for all."

https://www.sbmar.com/articles/tricks-tips-to-extract-and-remove-an-impeller/

 

[smitty477]

From Tony Athens:

"When installing a new impeller, throw out all that crap about lubing – Use any common white lithium grease (or similar grease) and life becomes easy for all."

https://www.sbmar.com/articles/tricks-tips-to-extract-and-remove-an-impeller/

That article and quote refers to the rubber impeller vanes.

 

[dwhatty]

That article and quote refers to the rubber impeller vanes.

Didn't the OP say "rubber impeller"?

And if not rubber but Neoprene, is there a reason one should one not use grease?

 

[psneeld]

my gosh...never do any work on a boat without special lab analysis....

 

[Pgitug]

From Tony Athens:

"When installing a new impeller, throw out all that crap about lubing – Use any common white lithium grease (or similar grease) and life becomes easy for all."

https://www.sbmar.com/articles/tricks-tips-to-extract-and-remove-an-impeller/

Sounds Good. [emoji108]

 

[SoWhat]

Bottle of glycerine from CVS. Also handy for cramming rubber hose onto barbs

 

[Simi 60]

Won't harm rubber - and works on shafts - keep some in your tool kit

I see what you did there

 

[Maerin]

Didn't the OP say "rubber impeller"?

And if not rubber but Neoprene, is there a reason one should one not use grease?

Actually, the OP's query was about lube for the SHAFT when installing a new impeller. So yes, the OP did mention "rubber impeller" but in the context of the shaft on which he's installing it.

Petroleum products and rubber have a history of not playing well together. The petroleum products soften the rubber. In the case of O-rings, it causes the O-ring to swell, bind, and perhaps slough off so it no longer seals. O-rings in use in engines are nitrile or another blend intended for use with oil, so it doesn't apply. O-rings used in plumbing fixtures are rubber or neoprene, and very susceptible to degradation from petroleum products. That's why Vaseline should never be used to lube plumbing parts, only silicone grease.

The take on Tony's assertion that any lube can be used on impellers considers that the amount of water flowing through the vanes will flush away any residual grease before it has an opportunity to react with the rubber. I just use liquid soap or glycerin, it cleans up easier and there's no question that it's compatible with the rubber, but Tony's got far more credibility.

As far as lube for the shaft/impeller hub, a waterproof grease that won't be washed away would help keep the two from locking together, that's the objective in making the next change out easier.

 

[Lepke]

For about 60 years I've been using waterproof grease. It's what many older engine manuals recommend. Probably pre EPA. I inspect impellers a couple times a year but they normally last 5+ years. Last ones I changed were installed in 2011. That is currently 2 Detroit 671s, An Onan MDL3 (Cummings) and Perkins 4108 generators.
I use a finger full of wp grease and coat the shaft, key and housing insides. It helps on the first start after changing the impeller by creating a greater suction because of the improved sealing of the vanes. I never have a problem removing the old impeller.

 

[ghost]

Superlube. I like it because I can use it on just about any pump, O-ring, hose or lots of other stuff so it’s always on hand.

 

[Comodave]

I use Superlube on the impellers as said above but also use it to hold O rings in place while installing them.

 

[SoWhat]

Actually, the OP's query was about lube for the SHAFT when installing a new impeller. So yes, the OP did mention "rubber impeller" but in the context of the shaft on which he's installing it.

good catch. I agree, waterproof grease on shaft. I use very thin layer of Quicksilver 2-4-C. I always have a tube on hand for the outboard.

 

[Ski in NC]

Yep, some sort of grease on shaft where impeller goes on. I use boat trailer wheel bearing grease. Bushing inside of impeller is some sort of metal alloy, won't affect the rubber. On the rubber I use Dawn as a lube to get the thing in easier.

And you know it is primed on startup when soap suds come out the exhaust!!

 

[Jetstream]

I've always used Dow Corning compound 4 on parts like the raw water pump shaft and the impellers themselves. Its a silicon grease and fantastic stuff for all sorts of marine applications. Available from Amazon.

 

[C lectric]

I lube the shaft and impeller hub with Dow Silicone grease.

The pump body I lube with liquid dish washing detergent. Just before I put the cover plate on I squirt a bunch of the stuff in. It will lube the impeller untill the water arrives. It also helps seal the impeller to the pump body to help with priming.

 

[HopCar]

The original question was what grease to put on the shaft. I’d put a little Never Seez on the shaft. It doesn’t matter as it won’t be in contact with the rubber.

It’s a good idea to put a little grease in the housing to lubricate the rubber for the first few seconds until water reaches it as well. You can use petroleum based grease if that’s what you have. The grease will be washed out in the first few minutes of running and won’t be in contact with the rubber long enough to hurt it.

 

[warren]

Hi you mentioned the rubber impeller. Westerbeke supply glycerine in their rebuild kits to put on the rubber impellers.
For the shaft that is separated from the water so I think it gets lubricated by the lubricant for the drive shaft, grease or engine oil?
Cheers Warren