Water Pump Grease Cup

[GregH]

Morning Folks!

So here I am thinking that I'm just about set for my first season with the A-4 in the water... water... water.. water pump... lube... grease cup... !?

Never used one before - how often do you tighten it in? how much do you tighten each time? - it has been filled and screwed back on enough not to fall off.. but other than that help would be appreciated oh wise sages!

This could be a make or break!

[tac]

Water Pump Grease Cup

I haven’t used the grease cup in years. I added the Moyer grease gun kit, which I see is out of stock:

https://moyermarine.com/product/remote-water-pump-lube-kit-ktas_03_88/

It doesn’t take much grease - my ***ORIGINAL*** A4 manual says 1 to 1-1/2 turns.

[tac]

As to frequency, an older manual says,

“Lubrication of the water pump seals is provided from the grease cup located on the pump body. Periodically tighten the cup until some resistance is felt to force the grease into the drive shaft housing. When the grease cup cannot be turned further in, refill with a good grade of water pump grease.”

[roadnsky]

I don't have a grease cup anymore thanks to my really cool MMI 502 pump.
But I have an old note in my maintenance book that says 1 to 1½ turns every 10-15 hours of engine operation.
YMMV...

[ndutton]

I found a tractor lubrication spec from 1919 that called for 1 grease cup turn every 2 hours of operation on rotating shafts (as opposed to eccentrics). That seemed like a lot to me but I confess my three old Oberdorfer pumps all have (1 had) scored shafts. There's a new MMI 502 on my boat engine because I grew weary of rebuilding.

[JOHN COOKSON]

Water pump grease is hard to find now days. I use boat trailer wheel bearing waterproof grease. It works great.

TRUE GRIT

[Sam]

We have a short season in Chicago and I am on my second water pump in 40+ years [with some shaft scoring]. I use common white waterproof lithium grease, fill cup at beginning of season and turn till grease oozes out, clean and refill and turn in about 1/4 - 1/2 turn every outing.

[Golfdad75]

Grease cup?

I have a grease fitting on my water pump, but I never knew anything about tightening until the grease oozes out. Can some help me? Tighten what up. I have 4 bolts that hold the plate on

[JOHN COOKSON]

The details the water pump grease cup are covered on page 2-8 of the Moyer manual.
Every 50 hours or so give the grease cup two there turns to force more grease into the shaft area. Refill the cup as necessary.

TRUE GRIT

[GregH]

I have a grease fitting on my water pump, but I never knew anything about tightening until the grease oozes out. Can some help me? Tighten what up. I have 4 bolts that hold the plate on

The grease cap itself screws on. You fill it with proper grease and thread it on. Tighten it until you feel some resistance. For myself, if I screw it all the way on and no resistance, then I take it off, refill it and do it again. Once I feel some resistance then I stop. Periodically I give it 2 turns to force more grease in - again until I feel a little resistance (very subjective I know)

[Smuggli]

New Pump

I can’t say enough good things about the new pump from MMI. It makes changing the impeller (and checking) so much easier. Also love the pressure. A great and worthwhile upgrade. No grease cup to worry about.

Scott Muggli
S/V Anna Rita

[JOHN COOKSON]

I can’t say enough good things about the new pump from MMI. It makes changing the impeller (and checking) so much easier. Also love the pressure. A great and worthwhile upgrade. No grease cup to worry about.
Scott Muggli
S/V Anna Rita

+1 on all of the above.

Here's another reason I like the MMI pump.
The original oberdorfer pump leaked at the back plate. (RWC engine) I could not stop the leak no matter what I tried. I think there was crud in the threads which prevented effective tightening of the backplate screws.The A4 was running @ 155-160. I don't know if the leak was reducing the water pressure or what.

I finally gave up and installed a MMI pump. Now I run @ 130-135. No other changes were made. It seems the MMI pump just plain a better pump and has more output.

TRUE GRIT

[sdemore]

I had to move my boat to the travelift, to pull the mast a month or so ago. Learned that even drained and winterized, water stays in the pump and freezes, and when you crank the engine, the impeller turns into two pieces (the rubber impeller part and the metal shaft collar). Also figured out that there is an important drain plug on the pump for a reason.

While replacing it, i took the opportunity to repack the shaft. Filled the cup, screwed it all the way in, the refilled he cup again for later use. I can't remember where I read that, but somewhere it said to screw a full cap full in when you've had it apart and cleaned off the shaft.

Not sure of why, but I had about twice the water flow from the exhaust with the new impeller. The water was about 32.00000001 degrees, so don't know if it will run cooler now.

[toddster]

Maybe the rubber isn't flexible enough at that temperature. Like Space Shuttle O-rings...

[Sam]

For decades my SOP has been after winter haul out to carefully pull out the impeller & shaft, coat the shaft with light grease or oil, wrap in plastic and store. This provides a opportunity for impeller and gasket inspection. [Note, angle burr the shaft edges to facilitate safe re install]' Also can check if grease cup is working properly squeezing grease inward and not just oozing out of cup. You should always keep a couple of $3 Moyer gaskets and an extra impellor on board. Admittedly you have to be a little bit of a contortionist and handle a long needle nose pliers surgically, but I can't remember when the last time I had broken impellor vane.