How to pin down source of water pump leak ?

1997 NG900 2.0 turbo.

I have a moderate (lose 1/2 liter/month) water leak from the pump or the seal into the engine. It leaks enough that there will be a large damp, not wet, spot on the driveway in the morning. I can see where it drips down onto the oil filter area from above by looking at the bottom of the engine. I can't see anything from the top as there is little viewing room.

I did change the pump last year and I did a very diligent job of cleaning the iron block entrance with #400 sandpaper until it was smooth and shiny again and carefully fitting the gasket to the pump, etc (bearings went on last one).

Any ideas on how to pin down the source? You can't see under the pump from the bottom or the top. I suppose I could just change the pump again, but if it is only the block ring gasket I could save a lot ' of $'s. Of course, it's not a quick job and I really don't want to do it twice more (i.e. change the block gasket and then have to do the whole job over again to change the pump if it still leaks).

Reply to
Bob
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I recently had the pump replaced on my 9000.

Took longer than expected since access is tricky and the gasket didn't do its job right first time. If it's been working OK for some time it's just possible you've got another failure.

I guess dismantling is the only simple way to be sure.

Graham

Reply to
Pooh Bear

Pour a bottle od Bars Leak down the coolant reservoir. Actually look at the instructions first, You may need only half a bottle. Bars Leak does wonders to small leaks like you described. Get it in Pepboys, Autozone or whatever auto stores you have in your neck of the wood. What have you got to lose?

Reply to
yaofeng

I've seen this stuff clog/reduce cooling passages in radiators so I am little hesitant... but I have not used it in years. Anyone have any recent experience in using this stuff and them doing a tear down later?

Reply to
Bob

What worries me is that once I pull the pump there will be enough drainage from the block that I will not be able to see where the leak was and I will just end up replacing both... unless I get luck enough to see a cut or gap in the pump/block seal. It's been too little time for long term deposits to lead me to the problem once I disassemble.

Reply to
Bob

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