New(ish) coolant pump leak....

[Steve Tinker]

Less than 2 years and 10,000 km (6,000 miles) ago, I replaced my coolant pump with a genuine Porsche unit I bought in the US from Flat6 (Jake Raby's outfit).
I know Jake only uses genuine pumps & so it has the plastic impellers and the correct ID numbers matching my original pump, so I know its the correct one.

Over the last couple of months I have been losing fluid at the rate of half a cupful (approx 100ml) every 500 miles or so - not a lot but even so, I don't like leaks in cooling systems.
I've tracked down the leak to the water pump - there is calcification just below the pump - so I pulled the belt, checked the pump for smoothness, end play (non) and re-torqued the retaining bolts. After a few hundred miles, the leak is still evident and looks like it could be coming from the bleed hole behind the pulley.
I've always had the impression that once fluid starts to leak from the bleed, its only a matter of time before the pump fails, ie it's an early warning device.
Can anyone clarify this. Am I on borrowed time ?
I would have thought that a genuine Porsche pump would last longer than 6,000 miles - the original one lasted 50,000 miles and looked perfect when I removed it.
Any helpful advice appreciated.

[san rensho]

Looks like you figured it out. Sounds like a bad WP. See if there is a warantee on the part. 6k miles is definitely way too low.

[Steve Tinker]

You are correct sr - genuine Porsche pumps should last longer than 6k miles.

As a matter of interest can anybody confirm that the "bleed hole" is there just to vent coolant leaking past the seal - I thought that the pump bearings were lubricated by the coolant itself and would not need a bleed hole.....
And how much weepage is acceptable?

[Steve Tinker]

That's just the answer I have been looking for - all is now revealed......

[howe]

Hey Steve,
from what I rember in the old days regarding water pumps you could replace the pump/ shaft bearing assembly which was in one piece.This was a sealed unit that pressed into the housing. The bearing was a sealed unit it did not come into contact with the coolant, the gland provided the water seal and yes if any did get past the gland it was drained via the bleed hole. Have you still got the old pump?

[Steve Tinker]

Hi Howard - yes still got the old pump (76,000 km), but looking at some other threads, it looks like its difficult to split the shaft / housing / bearing without damaging the unit.
If the weep gets any worse, it looks like I will be getting under the car and replacing the pump (again) - another $400, ahh well, its only money!

[Spinnaker]

Don't genuine Porsche parts have a two year warranty?

[Steve Tinker]

Yes they do, but the mechanics (read downside) is that I bought the pump in the USA and I live in Australia. I can remove the pump and ship it back to Flat6 who will send it to PNA who will dignose the problem ....etc, etc. Potentially it can take 2-3 months for an outcome which means that I could be without a car for that period - all for $400?? I think not....

I guess this is the biggest potential hazard from buying outside of the community you live in, but with Australian prices being in the region of 3-4 times the cost of what I can buy the parts for from the UK or USA its probably worth the the risk.

[Spinnaker]

I would send it back anyway. You may get a new pump out of it. Then you will have a spare to use in 3 - 4 years when you replace the new one that you are going to put in now anyway. According to the recommendations of Flat 6, you should replace the water pump every 3 years, if I remember correctly.