heinrich

Nicole thanks for posting this old thread for us again. So, the LASO pump I have failed almost immediately, and it failed in a very bad way. Again, the belt was at max tension so I can't blame the pump, as the wrong tensioner was installed and that was the real cause of failure .... but this pump shaft is now at an angle, having ground into itself .....

Susan: I would agree, looking at the casting.

borland

Funny how no one seems to know who, by name, is the US rebuilder(s) (remanufacturer) that Porsche-USA or 928Intl. uses. Just that they are not LASO?

I wonder what they have to hide? Could be they don't want to warrant their work against engine block damage.

MikeN

I'm with you. When I got my GT it had 22k miles on it but had all the original belt parts.....including water pump. Past maintenance showed that the timing belt tension was always watched and checked frequenty.......but the car still had the original belt......12 years old!

Of course the first thing I wanted to do was change the belt, but since engine cooling was so perfect and the pump didn't show any signs of leaks or bearing wear.......I left it alone. 6K miles later all is still perfect with just a new belt, rollers, and refreshed tensioner.

As others have said I think a lot has to do with how the belt tension was maintained over the years. You let belt tension get low for a long time and the pump "wears" to that tension. All of a sudden you put a new belt on with the proper tension and within a short time you have a pump failure. If the belt tension was always kept in spec, a new belt set to the same tension should not cause any trouble if the pump is in good shape to begin with.

WallyP

"I have long been an advocate of retaining a good pump instead of routine replacement during timing belt maintenance. It seems that I always get the cold shoulder from the board members with a vested interest, if you know what I mean..."

A very tacky observation, tarring all of us with a very broad brush.

For what it is worth, if you read back thru the archives, you will find that I have always suggested that anyone doing his own work leave a working pump alone when the belt is changed.

I think that if you talk to anyone who deals with 928 Specialists, they will agree that our first priority is taking care of your 928 and you, not selling parts.

heinrich

Interesting thoughts. I suppose there is value in the statement that:

"Many new pumps seize prematurely, so we're not replacing our known good ones till they seize".

But I can't see myself doing that.

heinrich

Wally .... in O&N's defense ..... he said that well over a year ago

maddox

My pump was fitted new at 87,000 miles (8 yrs ago) it has since done 32,000 miles, I am redoing T/Belt this year - that pump is staying in!

whall

Very Interesting. My car has 60k miles and I am doing the timing belt before summer. I was planning on doing the water pump as well but now......
I guess my biggest issue is risk. If a wp failure results in a engine failure, I want the wp replaced with one that is less likely to cause a engine failure. If the only risk is the wp dying, I would live with this rather than risking getting a wp that is more prone to failure than the one I have.
Hopefully this makes sense and I would certainly appreciate more opinions and experience from the people here before I make a decision.
Thanks

heinrich

If you instal a new belt onto an old water pump and tension it correctly, I believe the old pump will likely fail.

Jim bailey - 928 International

I base my opinions on 12 years of talking with thousands and thousands of 928 Owners/shops. Over the years when someone orders a water pump we ALWAYS ask , Do you need a new timing belt ? in more cases than I can remember they respond that the belt was just recently changed by the shop........ Now they get to pay to do that task all over again. Although more owners are working on their own cars and some are quite active on this forum the vast majority of 928 owners are NOT working on their own cars and a very high percentage never comment on this forum. Our experience with our rebuilder (who rebuilds for Porsche as well) has been extremely good BUT all rebuilts are not of the same quality. What have I done on my own 928s ? Mark Anderson on his including some rather expensive race engines ? When it gets a timing belt it also gets a rebuilt water pump ! every one is entitled to their own opinion. So I guess I would have to agree with Wally in that I try to treat customers they way that I personally would like to be treated. Besides there is no need to sell people "extra parts" when many have a hard time just keeping up with what the car really needs.

mark kibort

Only if the old belt was loose and now the new belt with higher tension is putting more pressure on the water pump.

as i have said, ive had two back to back failures on defective pumps, so i dont change mine unless it is makeing noise or leaking. (or the bearing feels loose)

MK

docmirror

Two comments here; First, 928 International happily sold me a WP, and gasket. They also happily gave me a credit when I didn't change mine during a TB job.

Second, I bought my car with an unknown TB condition, so I did the job right away. Upon inspection, my TB was just done recently, estimated < 5000 miles. The WP was done at that time, as the WP casing looked very new and shiny, and there was extra sealant on the gasket surface. I decided to leave mine in.

Time will tell if it was the right decision. Now, my opinion of using the timing belt to drive the WP and OP is that it's a stupid, stupid thing to do, particularly on an interference engine. I've done a bunch of TB jobs on different cars, and this is the only one I've seen that drives other things besides the cams and an idler/tensioner. The job was onerous on the Ferrari Mondial, with the engine in sideways, and the belts obscured by AC pump, covers, other belts. I think the routing of the TB in the 928 is crazy. Failures bear this out.

fst951

Hi.

Laso is a German OEM manufacturer of water pumps. They make fine units. They are a heavier casting but were extensively used in the middle year 944's. They also provide pump units for the boxters and 996's. I have never had a new or rebuilt water pump fail. Luck I guess. The plastic impellers do sometimes separate, but they don't do damage when they do. The metal impellered units almost never separate but do damage when this occurs. Not all rebuilds are the same. The person that does Porsche's is located in California and does nice work. We use a person out of South Carolina that we like a lot. No body stands behind a failed water pump....I think this discussion happened a couple of months ago when someones water pump failed...I won't name any names....failed and they didn't back it. I can't blame them as there are a lot of unknowns. For another $20 you could make a lot nicer water pump, that is for certain, but no one wants to pay the money. I mean the smart guys like Heinrich would, but who else. Just kidding, Heinrich.

Food for thought.

SharkSkin

Yeah, who the heck would want to do that?

heinrich

Make a 100 dollar better pump and I shall buy only that.