I was doing some work on the front underside of the car and noticed that I had
a leak on the left side bellow of the steering rack. I was going to purchase a seal kit to rebuild the rack, but since there was limited info on the Adwest rebuild, I opted to purchase a remanufactured unit from Welshent.
Should be here on Wednesday.
Does anyone who has replaced the Adwest rack on their vehicle have any pointers regarding the centering of the new rack prior to installation.
Also what type of fluid is used on the 1990 XJ40 rack?

 

Haven't replaced mine, have similar issue but leak is on RH side. In the past we would send out to have them rebuilt, once refitted, do alignment.

 

A professionally-rebuilt rack should come to you centered, but if you have any doubts, it's not difficult to count the total number of pinion turns from lock to lock and then set it as close to half-way between locks as you can.

Regarding the power steering fluid, the proper type is probably Dexron II/III. Mobil 1 ATF is a reasonable modern equivalent, or even better is Redline Oil D4 ATF. Dexron VI has a viscosity index significantly lower than the original Dexron II/III, and while it will work, it may not provide optimal system pressures.

Cheers,

Don

 

Thank you for the info.
I read somewhere that there was a hole in which a pin was inserted to center the rack, but I am not sure whether the article referred to the Adwest rack.
I will take your advice and count the turns from lock to lock on the new rack.
I will center the steering wheel before I remove the old rack.
I have not been under the car as yet, but I am hoping that the bolt used to connect the rack pinion to the steering rod is in an accessible location. I pressure cleaned the old grease and grime from the undercarriage yesterday to make life less greasy.
I don't know if the PO ever messed with the steering rack prior to me acquiring it. You never know what you will find on a car this old

 

SUCCESS: Remanufactured Adwest rack from Welshent arrived and installed with new outer tie rod ends. Alignment complete.
The question I now have is this:
The PS reservoir has a sticker on it that says to use mineral oil. I suctioned the oil that was in the reservoir and it is red like transmission fluid. I was of the opinion that the mineral oil was green.(I may be wrong about that)
Since the 'red oil' was super clean, and me unable to purchase the 'mineral oil' locally, I filtered and reused the oil to get the car rolling. I ordered 3 quarts of mineral oil which I will have on Monday to flush the system out
Prior to replacing the steering rack, I had a groaning sound from the PS pump and I thought it was because the fluid was low because of the leaking rack.
The groaning noise is still there.
Is it because of the type of oil in the system?
Do I have a bad PS pump?
Will the Mineral oil make a difference?
Thanks

 

Hi Sanchez,

I'm attaching the Power Hydraulic System Manual, which will give you some important information about your steering system. I am fairly certain that you need to use (green) Hydraulic System Mineral Oil (HSMO) and not Automatic Transmission Fluid or Power Steering Fluid.

HSMO has a very low viscosity of 18 cSt at 40 degrees Fahrenheit. By comparison, Dexron II, a common ATF in 1990, had a viscosity of 44 cSt at the same temperature. Modern Dexron VI has a viscosity of 29.8 cSt, and Valvoline Power Steering Fluid has a viscosity of 42 cSt.

By running one of these other fluids instead of HSMO, it is possible that system pressures and temperatures have been too high, which may have contributed to the leaks in the original rack and may have overstressed the seals and bushings/bearings in the pump.

I think a lot of owners converted to ATF or P/S Fluid when HSMO became more expensive and difficult to find, and the ill effects took time (years?) to develop.

Please let us know how the system behaves when you flush it with HSMO.

Cheers,

Don