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THE BONUS GUIDE: Porsche Manual Steering Rack
924S, 944 and 968

Cleaning, Regreasing, and Tensioning

You will need:
Hi-temp moly grease, about 8-10 oz
Socket set and socket wrench
Plenty of rags for cleaning

Before the project begins, take the time to inspect what type of rack you have by examining the part number. You will be able to determine whether it is a Sport rack or standard. You may need to wipe away years of grime to make this discovery. If you see “015” in the #, it’s the Sport rack, which was available as an option in the early 944. This rack is more desirable to “spirited” drivers and racers, thanks to its smaller turning radius; it is 3.5 turns lock-to-lock versus 4 turns offered by the standard. However, they are regreased the exact same way. Alternatively, the standard rack has a “011” in the part #.

Attachment 1362674

Refer to the following diagram as reference during the procedure, if needed.

Attachment 1362675

DISASSEMBLY

Lay your rack somewhere safe and be prepared to set parts aside. Of course, you will also be using a lot of grease.

1) Start with the intermediate shaft off so you can pull off the circular plastic dust cover.

Attachment 1362676

2) Under this dust cover, remove the two 10mm bolts that hold down the circular metal plate. The bolts are on either side of the pinion. Once removed, pull off the circular metal plate to reveal a bearing, which is seated in the housing. The pinion and bearing will be removed later.

3) On the other side of the rack housing, remove the two 10mm bolts on the diamond-shaped plate, and remove the plate. The bolt and nut in the center is used later to tension the rack, and can be left alone for now.

4) Under the diamond-shaped plate is a spring, a centering pellet, and a crescent guide. Remove these and carefully set aside.

Attachment 1362677

5) Mark the orientation of the pinion gear, because it must go back in the same way to line up properly with the intermediate shaft. Remove the pinion gear. Tip by Van: Attach the intermediate shaft and bolt to the pinion, and use it as a contact surface with a mallet to carefully force the pinion gear from the housing. Make sure to encourage the bearing to come out evenly on all sides, by carefully applying force with the mallet in various areas. Note that the pinion will need to rotate about a quarter turn as it is removed, and the rack gear will need to move slightly. The pinion comes out along with the bearing that was visible earlier. They are attached, and the bearing does not get replaced.

Your pinion gear should be free of imperfections. Note the gouges here, which can can cause inconsistencies in the steering.
Attachment 1362678

6) Remove only the right inner tie rod or, if preferred, both inner tie rods. To remove these, the large nut must first be turned away from the tie rod to release tension. If you’re wondering, both sides have normal right-handed threads. The tie rod ends do not need to be detached.

7) The rack itself (the long shaft with teeth) can now be removed. It is recommended, on a left-hand-drive rack, to pull the rack out on the left (driver) side of the assembly, to avoid having the teeth bite into the thick plastic washer on the right side of the assembly. In any case, slide the shaft out slowly and carefully.

The rack should also be free of imperfections. This one is damaged.
Attachment 1362679

CLEANING

1) With the rack and pinion out, the entire contents can now be cleaned. Tip: To aid in degreasing the inside of the housing, a cloth can be stuffed into the housing barrel and shoved all the way through with a rod. Repeat until satisfied. Tip: The lower bearing, which the pinion seats into, can be cleaned by moving a cloth at the tip of a screwdriver into the corners.

2) Clean all the little pieces, too.

REGREASING

Use a grease with moly additive, about 8-10oz.

1) With all the parts out, apply plenty of grease to the interior of the main housing. Tip: A sturdy plastic bag can be used like a baker’s icing bag; put grease in a bag, cut a small hole, and squeeze it out like icing.

2) Insert the rack gear into the housing, while pushing grease into the barrel-portion of the housing. Repeat, and slide the rack left to right until the system no longer accepts grease.

3 Fill the pinion gear hole with grease, and gently wiggle the pinion on until it is seated into the rack gear and the lower bearing. Turn the pinion by hand to see if everything is correct and the rack is sufficiently lubricated so far. Continue by gently tapping the bearing into place. It should be level.

4) Apply a small amount of course to the top of the bearing.

5) Return the circular metal plate to its location by putting it over the pinion. Bolt it down.

6) Turn the whole thing over, and put grease in the tension spring hole, and slide in the crescent guide.

7) Place the centering pellet in the cup of the crescent guide, put the spring over the pellet (so the pellet is inside the spring coil), and fill it with grease.

8) Replace the diamond-shaped plate, and tighten the two bolts.

TENSIONING

You can now tension your manual steering rack by adjusting the center bolt on the diamond-shaped plate. Tighten it down to reduce play and increase friction, and loosen it to reduce friction and increase play. Tip: One way to tension the rack to your liking is to start with the bolt loosened, and tighten it down until the play is all gone, but no further. Too tight, and the rack won’t turn at all!

Thanks for reading!

Attachment 1362680

Thanks to the internet for some of the pictures.