ROG100

Leslie,
We need facts not retoric please?
What failed and when - please fill in the blanks.
Roger

Jim R.

I'm due for a TB/WP replacement over this winter. So far, my rebuilt steel impeller WP has been fine, but if there is a better alternative to the standard rebuild I'm interested.

I'm sure the failure rate has been pretty low overall, but I do wonder about the second, third, fifth time these units get rebuilt.......those press fit components have to start getting sloppy.

Jim

SeanR

I'm along the same line of thinking. I use a slim line of Red ATV on both sides but I won't use Loctite on WP bolts. Putting locktite on the bolts is going to give the next guy ****s when he tries to change the pump. Granted, if you use the PTFE it might not be too bad, but I always use a touch of anti-seize. Thay way the next guy won't have to drill it out.

The bolts won't back out, and I suppose we just hi-jacked Rogers thread.

SeanR

Leslie, please tell Kevin to get on and quit using your log in. He's got too much tech to hide behind your name.

Again, sorry for the highjack.

ROG100

Paul - UK,
The laso casting is a sand casting and cosmetically rougher in appearance.
No issue when new at all, however the casting is softer than the pressure casting so when it is used in a rebuild there could be a problem with the interferance fit of the seal cartridge. That is why Jim at 928 Int will not accept Laso cores for rebuilds.

I to would like a better rebuilt pump with better components. There is just not enough volume to interest the rebuilders I have had contact with. To me new is the best way to go.

I will talk to the rebuilder in Canada but I am still left with cross border trading issues.

the flyin' scotsman

Roger.........let me know if you'd prefer a visit to the rebuilder for a operational look see. We have family in London.

Leslie 928 S2

Not much more to tell than what I have said above. We bought a new pump. Purchased end of January in preparation for the arrival of the black car. Installed towards the end of March, finally, killed the engine about a week ago. Take a look at my blown headgasket thread for more details.

Kevin tells me Laso is on the receipt, though he didn't notice it on the unit itself. The casting is very rough looking in comparison to others we've seen.

LOL....Kevin cannot type, so he makes me do all the posting for him. We used to switch back and forth between our names, but he kept forgetting to check if I was on, and was always using my name to send PMs to people anyway, so we just sort of gave up on it.

Besides, I'm much more fun to talk to, don't you think?
Roger, Kevin used to rebuild water pumps for fork lifts once upon a time. (He's done lots of different things, once upon a time. ) And we have a really good source for bearings like 20 minutes away from our house. Maybe you and he could talk about finding parts sources and working together on a new rebuilt water pump supply?

Stylemobile

Roger,

If you can do this, count me in for one as my car is due for the TB change. I am relatively certain that the WP currently in my car is a Porsche brand as the last TB/WP change was performed at a dealership by the PO.

Allen

SharkSkin

My WP has less than two years in service, so far so good. A couple years+ down the road when I need another, ~$50 delta between new and rebuilt would definitely sway me toward the new, provided that they have proven at least as reliable as the rebuilt units.

New WP vendor -- you're starting at ground zero WRT reliability stats. I have little to lose if a WP fails, except a day's wrenching. Others may be more cautious.

heinrich

I guess that's the problem ... it's a big Russian Roulette. Will my water pump fail? YES. WHEN it fails, will I need to rebuild my engine? LIKELY.

heinrich

YES

heinrich

The problem with our water pumps is really simple. Look at any other pump for any other car and you'll immediately see the problem.

Our pumps are wimpy. They are THIN and therefore the parts are not strong enough to hold the t-belt reliably.

Ask yourself a question:
How much thinner would I be able to make that pump, and still trust my valve train to it?

Answer:
None at all, it's barely holding the thing together as it is.

bronto

The light is slowly coming on for me....

I've understood from early on that the pump was driven by the timing belt, so changing both at the same time made sense. I've also understood that a belt failure on a 32 valve creates a boat anchor. But any pump failure I've ever had resulted only in overheating and coolant on the ground.

But yikes, pump failure causing belt failure... Weak casings, shaft goes flying, boat anchor. Glad more than even I have an non interference engine....

JPTL

Maybe because Porsche didn't have to design a water pump for a production car until several years into their existence. Something like the early 70's?
Just a theory, but wouldn't that make them pretty inexperienced in water pump design when compared to practically every other automaker?

Mike Frye

Wow. Never thought of it that way.

There really does seem to be very little 'meat' where the shaft goes through (and is supported by) the housing.

Roger, I know you're trying to gauge interest in using a manufacturer to make the existing design work well. Maybe a few of us can put our heads together to build a better mousetrap? I think Ryan suggested this as well.

I'd pay more for something that would no longer be 'the weakest link' in the chain, or at least one that had a failure mode that was guaranteed not to blow up my engine. If there was a sturdier housing and the shaft had grooves or steps to ensure it wouldn't slide in or out, the only failure modes would be seizing (smell smoke or temp goes up? shut it down, fix it) or leaking (see the leak in your driveway, trace it and replace it).

Just my .02.