Thaddeus

Since we're dreaming....

I suppose you could delete the roller altogether and run a shorter belt... but where would you get it? ...and it would run in a straight line from cam to cam...

Maybe you could run a chain loop between the 2 cams, and drive one of them with a chain from the crank. That would eliminate the belt!

Hm....

Thaddeus

Perhaps I should read my own sig and take heed...

sublimate

I think you'd set it up so it was always pumping, just a lot less if it's cold. The link said the voltage to the pump is adjusted between 4v and 12v, but it's never shut off - probably for just the reasons you described. And it wouldn't be too hard to put a cap on the inside of the waterpump to keep coolant away from the impeller shaft.
I agree it's probably not worth it - there are easier ways to gain 10-20hp. On the otherhand if your current pump locks up and your valves get bent it would have been really worth it. And if good waterpumps become hard to find...

Nicole

Why would you want to install a mittlelmotor pump (mid-engine pump) on a frontmotor (front engine)?

blau928

Nicole, na ja..... Der Co. heis Mittelmotor, aber wissen sie schon... das macht spass...!

SharkSkin

If good waterpumps become hard to find then I guess I will have to go out and find the best seal and bearing for the application myself and rebuild it myself. If they are that scarce it would be worth the time. I might even end up with a longer-lasting pump. Hmmm....

heinrich

I'll test it.

sublimate

Three cheers for the beer chugging, key lugging, purse hugging man.

Let me know if you need any help, although I'm probably about as far from you as possible.

SharkSkin

If I had a good core I could look into it... lots of other stuff clamoring for my time though. I wonder how feasible it would be to hog out the bearing area and weld in a piece that supports a larger bearing? Or to make a whole WP out of billet? Wouldn't that be a trip... billet water pump, with user-changeable bearings & seals, steel pin instead of a casting to hang the idler on...

heinrich

Dave I would be a major consumer of pumps like that ... that weren't pumps at all, just another roller receiver. In that sense we could instal that thing one time and never pull it ever again. Just replace belt, rollers and the electric pump periodically. I have a dead pump, easy to make it into such a thing ... just need the electrical pump.

SharkSkin

Oh, I was thinking improved pump. What you're describing would be a bit trickier... it would need a water fitting for each head, and another for the center added to it. Then the existing passages would have to be blocked. All in a very tight space. After I win the lotto I'll have plenty of free time, and I'll be building a machine shop and buying lots of 928s that I could test fit stuff onto... then I would be able to seriously consider such an undertaking.

heinrich

We (I) shouldn't forget ... the failure of the pumps is not a result of their driving water...... it's a result of a) the design calls for a weak mount and/or bearing or b) the belt runs on that pulley and stresses it heavily.

So, even deleting or smoothing the pump impeller would not save us ...... the precious item is the tbelt and its driven components. Therefore we would need to replace the pump with a flat piece of stock that holds a very strong, very well-mounted stud akin to the stud or boss on the idler. I think the design of the pump, coupled with the stresses and slaps of a timing belt, may just be too much.

Jim bailey - 928 International

It is extremely rare for a water pump to get so bad that the bearings seize especially with out the seals leaking first. Even when the pulley stops turning the smooth back side of the T-belt will slide on the smooth metal pulley. The car very quickly overheats with zero water circulation . Now the interesting part is what do people do when in that situation? MOST will try to make it off the freeway, off the bridge, home or to a gas station.......since it boiled over by that time they often will add water(hopefully waiting for the engine to cool but do not count on it )! Typically they will then start the engine to check if they can drive it .....if it was just low on coolant or something. What may have happened when they shut off the car is the rubber belt has vulcanized itself to the very hot water pump pulley and the belt breaks on restart. So did the seized pump break the belt or the insistence in driving after it was obvious that the engine just suddenly overheated ? Or the attempt to start it after it cooled down? So if your car suddenly overheats STOP driving at a minimum pull the air intake tube and stick your little finger down the hole on the cam belt cover. If you burn your finger you just might decide NOT TO START the engine.

heinrich

truer words have ne'er been spoken

Vilhuer

How about making water pump shaft longer towards outside and adding extra bearing to other side of pulley. It would need shaft, bearing support that mounts to pump casting and modification to cam belt shields. I think it would be doable and it would pretty much fix pulley side leaving only impeller as weak link. And it could be cured with same modified center shaft by adding bolt and plate to shafts rear end inside water area. It should keep impeller from coming off and ruining the block. Problems solved.