Replacing The Power Steering Rack In A 280ZX
Last weekend I replaced the power steering rack in my 83 ZXT. Haven't seen any posts about this on the group, so I thought I'd share some comments.
- Allow one full day if you haven't done it before.
- Before you start (preferably the day before) spray penetrating oil generously on the splines on the steering column located about 6" ABOVE the U-joint at the end of the steering column. These splines are intended to slip in and out slightly during the replacement procedure, and if they are rusty, the job will be MUCH harder. During the procedure, you have to re-fit a splined connector on the bottom of the steering column (below the U-joint) onto the splined shaft coming out of the rack; being able to slide the column up and down slightly is very helpful at this point.
- If you have a turbo, remove the heat shield which protects the master brake cylinder. It will make access easier, and it's only four small bolts.
- Have a set of tubing wrenches ready. The sizes of the two nuts going into the rack re 14mm and 17mm. You will NOT release the nuts on the hydraulic lines without tubing wrenches - you will destroy the nuts. Even using tubing wrenches, I had to use vise grips on the 14mm one - but managed to avoid damaging it so badly that I couldn't use the tubing wrench after it cracked loose.
- You will need a small drip pan to catch hydraulic fluid; some kitty litter to soak up stray fluid is handy and will keep your head and body drier and cleaner, too.
- You WILL need a "pickle fork" to pop off the outer tie rod ends. These are a conical fit into the corresponding part, and are much tighter than they appear. Auto Zone provides these wrenches as loaners for free - many other parts stores also do this.
- Have at least a quart of new fluid available; if you make a mistake and have to drain the system and re-fill, you may need more.
- The shop manual specifies lifting the engine slightly with a hoist, then using a floor jack to support and drop the crossmember. The hoist is not mandatory; you can substitute a "bottle jack" (small hydraulic single-piston jack) and use a 2x4 under the front end of the oil pan to lift the engine slightly. Be VERY careful not to lift far enough to break the fan blades on the edge of the shroud, as they have minimal clearance. You will have to locate the floor jack RIGHT next to the bottle jack to drop and lift the crossmember.
- Placement of jackstands for this job is critical. I put them on the front frame horns where they bolt to the body, and as far apart as possible. This is important because you will have these items in close proximity:
*Jackstands (either side)
*Bottle jack (probably on a short stack of 2x6 or 2x12 blocks)
*Floor jack (to drop and raise crossmember).
- I have recommended in this group before to avoid putting wood blocks between jackstands and the car whenever possible. Heeding my own advice, I cut some 14" long pieces of 2x12 and used them under each jackstand to get a reliable lift of just under 2" for each stand. This worked well, was very stable, and I'm glad I did it. The extra lift was most welcome. I now have four 14"-long pieces of 2x12 to use as stable bases for jackstands. Lovely!
- Even though it looks unnecessary before you start, you MUST raise the engine slightly to reach the farthest forward main bolt on the driver's side of the rack. It is impossible to loosen this specific bolt without the extra clearance provided by lifting the engine. I promise you this!
- Even though it looks unnecessary before you start, you MUST drop the crossmember to remove the old rack. The problems are: both the diameter of the main body of the rack -and the hydraulic lines which are part of the rack assembly. The lines run forward over the crossmember and cannot be removed without creating extra room.
- The most difficult part of the whole process was getting the single stud from each motor mount BACK into its hole in the crossmember after I had the main job done and had lifted the crossmember back into place. WATCH the motor mount studs while you are lifting the crossmember back into place! If you have a problem getting them lined up and you have to make a choice (esp. if you have a turbo) make sure the driver's side mount stud lines up and fight with the passenger side one - there's more room on that side. I finally got it lined up by loosening the two bolts which held the mount to the engine and prying with a stout crowbar to get the stud lined up, while simultaneously (using my third arm) releasing the bottle jack which was holding the engine up, allowing the stud to descend in the right spot. Then I tightened the two bolts on top of the mount (10 minutes each, 1/8 turn at a time...).
- Because there's no way to avoid having the engine suspended from a hoist or jack, be VERY careful about where you put your hands. Any hoist or jack failure could be Very Bad for your hands. Minimize your exposure to jack failure by watching where your hands go.
- Having said all this, the procedure is not extremely technically difficult, but I'd put it at a 7+ on a 1-10 difficulty scale. Expect to be patient and persistent, expect tight bolts, the need to have strong hands and put a lot of "grunt" on bolts which haven't moved for a long time. My arms and chest got a pretty good workout.
Fort Collins, CO