Steering Pump Weirdness
09-01-2002, 12:19 PM
#1
Pro
Thread Starter
Steering Pump Weirdness
Greetings all,
I have a question. I replaced my leaky pump yesterday with a used pump from Parts Heaven. I bled it, and there were no leaks.
I drove the car around for a minute, then to a couple of cul-de-sacs. I did about 15 laps to the left, then after a minute, 15 to the right. After this, my PS pump does not seem to work. It was as if the pump stopped working. Back in my garage I noticed that the belt was turning fine, and no leaks. My fluid level was good to.
Questions:
Does the pump get real hot? If not, maybe thats the problem.
After the car cooled off, I was able to duplicate the problem the same way.
Does the fact that it always happen after the right turns tell me its related to the rack, or something?
Do the bolts go in a specific way? The Haynes manual or Porsche manual doesn't say anything. There is a bolt with 4 holes, is this supposed to go in a certain way?
Thanks as always.
T.
<img src="graemlins/beerchug.gif" border="0" alt="[cheers]" />
I have a question. I replaced my leaky pump yesterday with a used pump from Parts Heaven. I bled it, and there were no leaks.
I drove the car around for a minute, then to a couple of cul-de-sacs. I did about 15 laps to the left, then after a minute, 15 to the right. After this, my PS pump does not seem to work. It was as if the pump stopped working. Back in my garage I noticed that the belt was turning fine, and no leaks. My fluid level was good to.
Questions:
Does the pump get real hot? If not, maybe thats the problem.
After the car cooled off, I was able to duplicate the problem the same way.
Does the fact that it always happen after the right turns tell me its related to the rack, or something?
Do the bolts go in a specific way? The Haynes manual or Porsche manual doesn't say anything. There is a bolt with 4 holes, is this supposed to go in a certain way?
Thanks as always.
T.
<img src="graemlins/beerchug.gif" border="0" alt="[cheers]" />
09-01-2002, 11:59 PM
#3
Drifting
T951, sorry to hear you are having problems with your power steering pump.
One of the guys in my PCA region recently showed me an article from the July issue of 911&Porsche World magazine on rebuilding a 944 power steering pump. It says you can rebuild the pump with a Porsche rebuild kit in an hour or so. Sorry I donn't have a copy of the magazine but maybe someone else on the board does.
One of the guys in my PCA region recently showed me an article from the July issue of 911&Porsche World magazine on rebuilding a 944 power steering pump. It says you can rebuild the pump with a Porsche rebuild kit in an hour or so. Sorry I donn't have a copy of the magazine but maybe someone else on the board does.
09-02-2002, 12:25 AM
#4
Drifting
I looked into some of the info that I've downloaded from the web since buying the 944 and here is something that may help you:
Subject: Re: Power steering leak, 7/10/99L
From: griffs@griffiths.com
EXTERNAL LEAKAGE:
Where to look for fluid leaks,
1) If you remove the bellow's (rubber boots) which cover the inner tie rod and the rack's ends.
2) Inspect the section where the steel tube meets the aluminum casting.
3) Inspect the four "banjo" bolts that attach the two steel hydraulic lines to the rack.
4) Inspect the two banjo bolts that attach the high pressure line from the pump and the low pressure line to the reservoir (spelling may be off today).
5) Inspect the top of the pinion housing, this is the aluminum housing on the driver's side where the steering wheel shaft connects to the splined upper pinion. Here check round the aluminum cap and also the top portion of the pinion's spline (spool valve's torsion bar assy), the later is difficult to see.
6) Inspect around the power steering fluid reservoir and its related hoses and finally the high side hose from the pump.
7) We have seen fluids from other components blown back onto the rack of which would not appear are "red" as the ATF fluid used in the system.
The system uses Dexron type II or III (only), attempts to use seal "revitalizers" may have the potential to swell o-rings, hoses and seals within the system.
Attempts to "seal up the boot" will not be effective as the system pressure is too high.
INTERNAL LEAKAGE:
If the rack fails to provide power assistance to one side only, then it is most likely a spool valve failure or related sealing area of that circuit. If the rack fails to provide power assistance in both directions, then it could be either the power steering pump, rack piston or both spool valve circuits. In most situations the solution is to replace the rack.
Can the rack be properly repaired by the average person? Sometimes and sometimes not. It depends upon the condition of the rack. If the rack shaft's sealing surfaces are severely rusted or damaged it's not economical to repair the shaft. If the spool valve housing (aluminum section) has excessive wear grooves corresponding to the spool valves high pressure sealing rings, then you might as well discard the housing. It takes the right tools and patience to properly rebuild a rack. This is not to say that it can't be done, just that there are other things to do with your time.
Subject: Re: Power steering leak, 7/10/99L
From: griffs@griffiths.com
EXTERNAL LEAKAGE:
Where to look for fluid leaks,
1) If you remove the bellow's (rubber boots) which cover the inner tie rod and the rack's ends.
2) Inspect the section where the steel tube meets the aluminum casting.
3) Inspect the four "banjo" bolts that attach the two steel hydraulic lines to the rack.
4) Inspect the two banjo bolts that attach the high pressure line from the pump and the low pressure line to the reservoir (spelling may be off today).
5) Inspect the top of the pinion housing, this is the aluminum housing on the driver's side where the steering wheel shaft connects to the splined upper pinion. Here check round the aluminum cap and also the top portion of the pinion's spline (spool valve's torsion bar assy), the later is difficult to see.
6) Inspect around the power steering fluid reservoir and its related hoses and finally the high side hose from the pump.
7) We have seen fluids from other components blown back onto the rack of which would not appear are "red" as the ATF fluid used in the system.
The system uses Dexron type II or III (only), attempts to use seal "revitalizers" may have the potential to swell o-rings, hoses and seals within the system.
Attempts to "seal up the boot" will not be effective as the system pressure is too high.
INTERNAL LEAKAGE:
If the rack fails to provide power assistance to one side only, then it is most likely a spool valve failure or related sealing area of that circuit. If the rack fails to provide power assistance in both directions, then it could be either the power steering pump, rack piston or both spool valve circuits. In most situations the solution is to replace the rack.
Can the rack be properly repaired by the average person? Sometimes and sometimes not. It depends upon the condition of the rack. If the rack shaft's sealing surfaces are severely rusted or damaged it's not economical to repair the shaft. If the spool valve housing (aluminum section) has excessive wear grooves corresponding to the spool valves high pressure sealing rings, then you might as well discard the housing. It takes the right tools and patience to properly rebuild a rack. This is not to say that it can't be done, just that there are other things to do with your time.
09-02-2002, 12:32 AM
#5
I found out the hardway that the power steering pumps were different for various models and years of 944. The pressure loads vary. I also found that the bleeding process can be deceptive. I resorted to lock to lock with wheels on and off the ground, engine running and off. Finally everything came around.
