Pesky Water Leak Near Water Pump

[Rick_Powers]

Hello friends,

I recently replaced my water pump with a brand-new MMI water pump.

The purpose was to eliminate a slow water leak that only occured when the engine is running.

So, I installed the new pump (much better design!), and there is STILL A LEAK !

What is most perplexing, is that with very careful observation the trickle of water is not coming from the impeller side of the pump, where one would expect water to be, but rather (apparently) from the mounting flange side of the pump. It almost appears to be weeping out of the engine block.

See attached photo with indicating arrow.

As I run the engine, I can watch water weeping out of the junction between the pump and engine block. Is this possible? Is that not the oil side of the pump?

What should I do?

Thanks in advance,

-Rick Powers, Palo Alto, CA

[sailbristol]

leak

my water pump was doing the exact same thing Uncle Don suggested clamping down on out put line to help the seal seal better but it didnt work in my case more water came out had to return pump still waiting out come

[s/v Dearbhail]

Check and seal the two bolts that mount the pump to the engine.
I think you'll find your leak there. The leak is water not oil.

[Rick_Powers]

Thanks Mark

Hi Mark,

Do you suggest that water is leaking out the bolt threads?

Sound possible. Just not sure how water gets to there.

Do you mean that I should remove the bolts, coat the threads with sealing (gasket maker) and re-tighten? Otherwise how?

If it is that simple, hooray!

-Rick

[rigspelt]

Sure it's not coming from the weep hole in the pump?

[Rick_Powers]

Yes, pretty darn sure

Thanks for your input.

Yes, pretty darn sure.

The weep hole is towards the impeller side.

Water seeps in from the engine block side.

Also, it is a brand-new MMI water pump, so I'd hate to think that the new seal is leaking.

Do you agree with the previous post that the bolt holes could be the culprit?

It's not too hard to remove the bottom flange bolt, coat it with gasket goo, then retighten.

I'm shooting for a dry (non-leaking) engine. Is that realistic?

-Rick Powers, Palo Alto, CA

[Dromo]

Just a thought

Did you replace the hose on the output side of the pump, that supplies the engine cooling system? I think any kind of leak above the pump would run down the underside of the hose, dripping at the bottom of the pump .It would explain the previous dripping of the old pump. Hope I am wrong.
Regards Rick

[Rick_Powers]

To Dromo, thanks

Thanks,

I will look at that tomorrow. Possible!

Is it OK to smear the lower bolt with gasket goop and re-tighten it?

Any danger there?

-Rick

[roadnsky]

All of the above!

Rick-
Do both of the bolts with Gasket Goo AND really tighten that hose clamp on the output. Now if you didn't replace that hose; well, that is very likely the spot.
When I replaced mine it was the hose that had a very small (but aggravating) leak. I tightened that clamp and...
dryness!!
-Jerry

[s/v Dearbhail]

Rick, the bolts pass through the gasket, if the gasket goo doesn't seal surrounding the bolt then water can find it's way to the bolt and seep out around it. The weep hole is certainly an option, but with a new pump from Don?

[Rick_Powers]

Still Leaking!

Hello friends,

Thanks for all the good advice.

I have done the following:

1) Remove water pump flange bolts, smeared with gasket goop, and re-tightened.

2) Tightened the hose clamps coming to and from the water pump.

3) Smeared (carefully) gasket goop around the mounting flange, just for good measure.

However, it STILL LEAKS!

What is so perplexing is that the water does not appear on the top of the engine case mounting flat spot (see red arrow in photo), but rather appears just below that (see blue arrow) and pools on the rubber engine mount.

I can't see how that is even possible, as water exists only on the impeller side of the water pump.

Where the heck is that water leak coming from??? It's driving me crazy...

Thanks,

-Rick Powers, Palo Alto, CA

[knitchie]

Finding Pesky Leaks

Rick,
Maybe it's time to clean and dry the entire area and power it up with baby powder or talc. That may help you discover the source and path of the water.
Ken

[Dromo]

Baby powder

Ken, what a great suggestion! That would work anywhere on the boat.
through hull fittings, deck fittings, Hatches etc. I'm looking forward to hearing any results.

Rick, this is a long shot, but did you look for signs of water in the oil?

Regards, Dromo (Rick)

[Rick_Powers]

Talcum Powder

Ken,

What a great idea! I had thought of that myself, and I'm about to go and buy some for just that purpose. I'll report back tomorrow.

Rick, no water in the oil. Nice and clean.

OK, back to it!

-Rick

[Rick_Powers]

Don Moyer Advised...

Although the last thing I would suspect, Don M. suggested that it might be a leaky bearing-seal, and that water is dripping out the weep-hole on the underside of the water pump, tough to see from the top.

Tomorrow I will dry the area, apply talcum powder, cover the weep holes with duct-tape, and see what happens.

Don, thank you for personally phoning and leaving a very nice message on my home answering machine. You made my day!

-Rick Powers, Palo Alto, CA