How to rebuild a power steering rack F355

Jumping in head first, eff the torpedo. This is going to be a step by step instruction on how to disassemble, source the parts, and rebuild a TRW power steering rack on a F355.

Very few of us will ever attempt the removal of said rack, let alone rebuild it. But for those who are absolute stooges and want to get knee deep in this job. Here it is, with pictures, and step by step instructions.

First, start by removing the two auxiliary hydraulic lines from the housing to the rack.
Second, with the rack on your bench, remove the side plate that keeps the pressure on the shaft against the pinion. Two allen screws, 2 shims, 1 paper gasket. Notice the last picture with the round pressure plug with the Teflon insert.
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Pick out the rubber seal at the top of the pinion shaft. There is also a spring that keeps pressure on the round seal. Then remove the circlip holding the pinion column in the housing.
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At the bottom of the housing, remove the pressed-in cap to expose the retaining nut for the pinion.

1. You can pry it out. I could not figure that out in 30 minutes, so...
2. I chose to weld in a nut, screw in a bolt, and a cheap slide hammer makes minced meat of this task. Pick your poison.
3. Use an impact wrench, remove the nut.
4. Use a brass drift, and a hammer to knock the pinion out. It comes flying out so be prepared.
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Then remove the two tie rods on both sides of the rack. I used a combination of two pipe wrenches on the driver side, and a large pair of channel locks with a pipe wrench on the passenger side. Both are right handed threads.
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Here comes a non-obvious step. You need to remove the 2 inch plastic plug at the end of the shaft.

1. push that rack all the way into the housing. There will be a **** load of fluid that shoots out 6 feet streams so get plenty of towels to mop that up.
2. Notice the elongated hole at the end of the housing on the passenger side. 1/8 in wide, 1/2 wide, with a head of a pin barely visible. That is the retaining pin you have to remove.
3. Use a pair of needle nose pliers, insert the tips into slots in the plastic plug and rotate clock-wise (for me it was cw). The end of the pin will slide out, insert a flat head screw driver and gently pry the end over the edge of the housing, continue until you see the other side of the pin. You have to rotate over 180 degrees. Then remove the pin.
4. Insert a slide hammer with a pilot bearing attachment into the plug, pull out the plug and the seal at the same time. There is no way to do this w/o a slide hammer.
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Now slide the rack out from driver side to passenger side, all the way out. Set it aside

The picture shows the end of the rack, driver side, with the seal orientation (I put the seal back on the rack to take a picture of its orientation). Unlike a manual rack, the power steering rack has a solid round plate in the middle of the rack with seal on it so that the hydraulic fluid has something to push against.
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Now remove the seal at the other side of the rack. It is buried over a foot inside the housing and forget the Autozone pilot bearing puller, it does not work. I happened to have a smaller pilot bearing puller that worked for this task. I removed the hammer head from the shaft to get enough reach, turn the shaft to lock the pilot bearing prongs against the seal, and pry the end of the slide hammer against the shaft housing using a fork (a ball joint removal fork). Get the idea, this job is requiring all kinds of tools.
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Remove the circlip at the bottom of the pinion housing, turn the housing right side up, use a long brass drift, knock out the bearing from the top.
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Lock the steering rack in a bench vise, with the housing bottom up. There is a shaft seal that is half way down the pinion housing. It is retained in place by a spacer which is pressed in tightly.

Use a MAPP gas torch, heat up the housing area where the spacer is, to about 250F, and use a brass drip and hammer to knock the spacer out. A few firm knocks and the spacer falls out of the housing expanded from the heat.

Reach in and drive out the shaft seal from the housing. I had to destroy it to get it out. So be it. I won.
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That completes the disassembly process. I am taking these seals to an industrial supply house tomorrow to get replacement. So far, my research shows that a 95-97 Volvo 960 rack is nearly identical from TRW and there is a seal kit for that rack. Buy it at your own risk. I will buy it just to see if it fits.

The link is: Volvo power steering Rack Kits / 960 Series / 95-97 / (Cam/TRW Design)

The shaft seal which I destroyed has this part number from TRW: 34002485 which matches the dimensions to a Corteco seal p/n 12014254B. The picture below shows the two seals and the oring I will try to get from vendor. It does not show the Corteco seal above.

Time to clean the rack, pinion, housing up in anticipation of re-assembly. More to come.
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Wow. Fantastic! Thanks for this.

 

Very cool stuff man! You're making it look easy.

I need to pull one side of my rack apart in my 348. The bush has collapsed and I am going to try and cheat by replacing it with the rack bolted in the car.

I think I can do it, hell............I can do anything!

Looking forward to seeing more pics, thanks for sharing mate.

 

Great work Mitchel!

 

Why is it called a rack?

 

Great thread Mitchell!!

 

This is the kind of info that makes this forum great. Thanks for all the details and pics.

 

Because it has two ... ends. I have to admit it was pretty flat for a rack. Very unmemorable.

 

Because it's an instrument of torture?

Were there any signs of failure or wear/tear, Mitchell? What was the inspiration for this intrepid adventure?

 

It was leaking out the broken boots, not much but leaky. Then I spent days getting the effing thing out and I sure as hell was not going to put it back without rebuilding it. Besides, we needed a thorough rack rebuild thread, complete with whether the Volvo seals will fit.

Rotex in Gardena quoted "anywhere from $200 to $700 to rebuild it, plus $100 shipping. It just offended me to no ends. Nobody will source or sell me a rebuild kit, and at some point in time I just said eff it, I am doing this myself.

I inspected the "rod" and it is in very good shape with no bad wear. The housing is also in good shape, just needs the seals replaced.

 

Nice write up and pictures.

 

Which F355 is this?

 

The red one.

 

Awesome, just awesome mine is gonna need fixing aventually. I am adding this to the diy sticky. Thanks Mitchell

 

OK, the bad news is this company PSkits has terrible customer service. But the good news is the power steering kit for the Volvo is exactly what the F355 rack needs. There will be some left over bits, but this ain't no Volvo.

First pix is the kit bag, second are the contents, and third is where the various seals go. The metal retainer ring is 3rd from the top. Below that is the small seal barely visible.
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Now that you have cleaned everything, first put the small seal in from the top of the housing. Spring side facing up toward the fluid. Tap it in place with a 22mm socket on an extension. Use some WD40 for lube.
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