8 replies to this topic

[mylz87]

I was recently told by a Porsche mechanic, that by not replacing the water pump at the same time as the timing belt, it could lead to a broken tooth on the water pump, which would result in catastrophic engine failure, resembling a broken timing belt.

Something about the alignment of the grooves on the timing belt and the teeth on the water pump wearing in together. Putting a new timing belt on an existing pump would stress the teeth on the pump.

This is a new one on me, but hey, I'm rookie on these cars.

True?

[banditsc]

The water pump pulley is smooth, the backside of the belt drives the pump. So he has know idea what he is talking about. Now some mechanics will like you to change the pump every belt change as it add's to there pockets, not that it needs to be. If the pump were to seize, it would eventually take out the timing belt and cause a lot of damage. Personally I don't change the pump every change, they should be good for a couple of belt changes before they probably should be changed for piece of mind.

[94SilverCab]

I agree, no reason to change wp with every belt change...

Jay

[tamathumper]

Wow. Run, do not walk, back to that mechanic and pimp-slap the shiznit out of him.

In my humble opinion.

[ds968]

Nonsense. Maybe every 2nd belt change, or if you subscribe to the < 40k miles change interval, you can probably go even longer ( at 3rd change ). Unlike the 944 WPs, these pumps are much better made and typically last more than 100k miles. The " tension " change of the new belts possible affect/ load on the WP is a myth. Same as the myth that a new variocam chain will affect the cams teeth.

Edited by ds968, 30 March 2013 - 08:20 AM.

[mylz87]

Thanks for the feedback!
Needless to say, I won't be visiting this mechanic in the future. I thought it sounded a little weird, so thanks for confirming my thoughts.

[Scott Collins]

mylz87,

My original pump lasted 90k miles and 19 years. That's pretty good. It was not spinning smoothly when I pulled it along with a top end rebuild.

Do you know the service history of your car. For instance, what's you mileage and when was the timing belt last replaced? Time and mileage are both important. Is there any history of the water pump being replaced?

Depending on your situation, it might be wise to replace the pump.

-Scott

[Chris Vais]

I've changed my belts every 30,000 miles since I purchased the car in 1996 and I've only replaced the water pump one time after it indicated that it was about to fail. The car has 146,000 miles on it.

Edited by Chris Vais, 01 April 2013 - 10:42 AM.

[mylz87]

Guys,
thanks for all the feed back. I'm looking at a 92' with 125k on it. Timing belt was changed last winter. After reading a few of the other posts, I have a much better feel for the car & what the $$ purchase price should be.
The car needs some TLC, but could be a good weekend driver with 3-4K investment.

Thanks again.
Mylz87