Peter F

I know this is a really long shot but wan't to check anyway.
Is there anyone with a spare PSD pump on the list for whatever reason?
Mine is spinning but it will not pump any pressure into the reservoire.
John Veninger was kind enough to point me to Sterling but he had sold his pump a month ago on Ebay
I will be in the US first two weeks of Nov.
Any tips highly appreciated, this is only one of a number of things that needs attention on my newly aquired 1990 GT(without sunroof).



Cheers/Peter

slate blue

Hi Peter, hope your good, if I remember correctly you bought a GT box like myself from a wreck? But I thought your box was a LSD not a PSD? Anyway have you looked into the electronic side of things, i.e how are you going to control the PSD? I take you know how Porsche controlled it? I have also decided to run the PSD system despite what people say about its erractic operation. I note that BMW has just installed a very similar system in the new M5. Figure if the electronics are right it can't be too bad.

What I like about it is that it has 100% locking ability, also it has quite a few clutches in there too, with the option of using the better GTS clutches. I thought what I might do if possible was have a look at the Porsche parameters for the operation and then get a MOTEC system to run it. I could modify it how I liked.
BTW how much did Sterling get for it on EBAY? I think the way I will go is this, I will buy another wreck this time one with PSD and transfer it across. I also want to run the digital dash, I like them. That way I will have all the wiring and the stock computers to get it up and running in the first place.

I would be interested in your thoughts, just in case you have a different approach. Good luck and please keep me informed.

borland

If the pump spins and you have dislodged the air, then it should build pressure. Your saying you removed the air but it doesn't build pressre? That doesn't sound right to me.

I would remove the pump assembly from the car, then shake and invert it. That might need to be done a couple of times, but should work.

Removing the pump assembly is easy; just disconnect the electrical connectors, pressure line ahead of the differential and then the rubber mounted bolts.

As for flushing the slave (without applying 12V jumper that is), while you have the pump pressure line disconnected, connect a hose to your brake fluid bottle, and with a mity-vac, pull fluid thru the bleed screw until the fluid is clear.

Peter F

Hi Greg, doing just fine and just bought my second 928.
You are right I did buy and installed a -89 GT gearbox in my -81S from a wreck.
This problem are with my second 928 that I just bought.(in my sig.)
Brakefluid level was below the minimum mark in the PSD system.
I could hear the pump spinning and filled new fluid.
Have been trying to bleed using John Veninger/Louis Ott write-up with no luck so far.
Did try and move the assembly and have now taken it out of the car.
Borland, do you mean to shake and twist it without activating the pump?
I'm not sure how to remove the air trapped in the system if that is the problem.
What are the chances for the pump to internally have worn due to low fluid level.
If it has been running like that in a constant mode for a long time?
Anyway I'm stuck at the moment, next would be to open the system and look for dirt/blockage or worn out o-rings.
Don't know what Sterlings pump sold at on Ebay.

Cheers/Peter

Jim bailey - 928 International

We do not have one here at 928 International.

borland

Yes shake it and twist it out of the car, then reinstall it and apply power. You can try running the pump with the pressure line to the slave disconnected.

I see no reason to suspect the pump to be damaged by running with an air pocket. The fluid provides lubrication. Completely dry is not likely.

Peter F

Hi Borland,

what you are saying are like music to my ears and I hope you are right.
Will try tomorrow, time for bed now in Sweden.

/Peter

John Veninger

Try Sterling.
sterling@928sg.com

Vilhuer

One local with PSD pump problems I mentioned in earlier thread even had plugs on pump body that block ends of small channel drilings remover to check those channels are clear of debris. Removal was done with some interesting electric process without damage to pump body. After cleanup new plugs were inserted. Still no pressure and pump internals are not worn at all.

Greg, you're sick!

PS. What's the story on pistons? PM me if you like, thanks.