Water pump intentionally leaks when new?

[Simeon]

A few months back I installed a new Graf water pump. No dramas on installation, test run and everything was fine. A few days later after taking the car for a run, I noticed coolant leaking from the bottom of the pump.

 

Thinking I had stuffed something up, I got a new gasket and prepared to dig in. While I waited for the gasket to arrive I noticed that I had no more leaks. I even read a thread on here regarding an 'intermittent leak' from a water pump, so I thought I might be better swapping the pump again. There seems to be too many stories of unreliable pumps. 

 

I bought a new HEPU water pump off eBay and when I read the instructions I found this:

 

 

Pump

 

 

so, does that mean that there is a seal in the water pump that needs to swell up in contact with the coolant or similar?

 

I guess that I will keep an eye on my existing pump for now and swap it again if I see it leak any more coolant. I suppose having a new one on the shelf should ward that off. 

[ingramlee]

Same thing happened to me...sort of. Mine ran for about 3 weeks before it started to leak, driving occasionally.  I replaced it with another Graf pump and gasket and it hasn't leaked again yet. Its been a couple of months now.

[02Les]

I too had this problem. The pump was a year or so old, and having arrived at the 2009 Vintage it decided to pee on the ground.

I never got around to changing it so it's still on the car now; I have never noticed it leak since.

 

 

[Mike Self]

If the leak is coming through the weep hole--located at the 6 o'clock position directly below the pump shaft, at least on an old(er) pump it's a sign of the seal wearing out/failing.  Inside the pump there's a spring-loaded seal that bears against the pump's shaft that keeps coolant away from the pump's bearings.  I've not had a 2002 pump apart so I don't know if this is a lip seal (similar to a crankshaft seal) or a carbon flange.  Regardless, it really shouldn't leak at all.  

 

I'd keep an eye on the new pump and see if it continues to weep.  A good test would be to drive the car around with the radiator cap tight and check for a leak.  If you find a dribble from the weep hole, then loosen the cap, thus relieving pressure in the system and see if the dribble stops.  If it does, I would suspect a faulty seal, which will eventually cause bearing failure.  Too bad modern pumps don't have grease fittings--my '59 Renault has one, and I've never had a water pump wear out.

 

So far I've only had dribbles when the pump was near the end of its life; you can tell the bearings are going out if the fan has axial play--i.e. you can grab the end of a blade and rock it back and forth.  

 

cheers

mike 

[TobyB]

It's not supposed to do that...

I too would watch it,and be tempted to replace it and send the old one back under warranty.

 

t

[adawil2002]

Had my water pump replaced two years ago and there was no weep at all after installation.

[JerryC]

Water pumps can do strange things and still not leak, but they're not supposed to leak. Better get a backup unit on order now.

 

I needed to change the alternator on my Chrysler last summer (really noisy bearings), and by tugging on the water pump "because I was already in there" I discovered an extremely wobbly pump shaft - one of the worst I've seen. Despite that, there were no signs of any leakage having occurred. I replaced the pump anyway.

[robspeed]

If the mfgr says it may leak a short time and then stop, I'd take them at their word.

[TobyB]

'trust but verify' simply means you don't trust.

 

And I wouldn't trust a seal that didn't.

 

Not with an engine.  Hepu's not going to buy you a new one of those...

 

But hey, I use Graf pumps...

 

t

 

[Simeon]

Graf is what's on the car now. The HEPU one looks exactly the same (same casting, finish etc)

[RMBaiada]

While removing my brand new tropical fan for an electric fan install, I noticed my brand new Graf water pump shaft had a very small amount of in and out movement.  I couldn’t feel any movement side to side, but it is very hard to tell.

 

Does anyone know if this is normal? If it is a problem, I want to swap it out while the radiator is out of the car. Fortunately, I purchased it at AutohausAZ, given their 3 year warranty.

 

No water in the engine yet in the engine and I have not started the engine yet since the rebuild.

 

Thank you,

Michael

Edited July 24, 2020 by RMBaiada

[02Les]

On 12/20/2016 at 10:26 AM, 02Les said:

I too had this problem. The pump was a year or so old, and having arrived at the 2009 Vintage it decided to pee on the ground.

I never got around to changing it so it's still on the car now; I have never noticed it leak since.

 

 

 

Hehe. 3.5 years later and the same water pump is still on the car and never seen it leak again. Perhaps it needed 'running in'?