88 Steering Rack repair (Page 1/3)
fierosound JUN 02, 08:12 PM
NOTE: The 88 steering rack is unique to that year.
84-87 are different and can't have this particular problem described.

One of our members had been complaining about hard steering on his 88 - including binding and clunking.
A "professional mechanic" told him there was something wrong with the steering column internally.
He brought it over so I could have a closer look at what was going on. The car was barely steerable.
By the time we got it in the garage the steering wheel was upside down with the front wheels facing forward!

Mechanic misdiagnosis - there is nothing wrong with the steering column. It was the rack itself.

The pinion in the 88 rack has a ball bearing on the bottom end and a lock nut securing the shaft.
A snap ring locks the bearing in the housing and a dust cap is pressed into the opening.
This lower ball bearing has come apart and has literally "lost all its marbles".

The binding and clunking were the pinion teeth jamming on the rack teeth, then jumping over by a tooth in the rack.



This is the end of the pinion with dust cap removed.
The ball bearing has literally "lost all its marbles".
LOL
It did not fail because dirt got in the bearing.
This end IS NOT open and exposed to water, road debris etc.
It just looks like that because the old grease has dried out.

That ring you see on the pinion shaft is the bearing's inner race.
The outer race and snap ring are still in the housing.
It's obvious this has been broken for some time to grind up the nut on the end of the shaft.




EDIT:

I removed the snap ring and cleaned up the face of the outer ring.
All I can read is FRANCE and the number 630499
I haven't managed to find it or a cross reference to anything yet.

The bearing is 10mm ID x 30mm OD x 8mm wide
See below - DON'T WANT factory part anyway.


------------------
Calgary time/temp

3.4L Supercharged 87 GT Click me
Super Duty 4 Indy #163 Click me

[This message has been edited by fierosound (edited 07-18-2018).]

fierosound JUN 02, 11:34 PM
GM had similar problems with lower rack and pinion bearings on their other cars.
http://www.ebearing.com/news2002/112101.htm

"A lower pinion bearing in the rack & pinion may separate, causing the driver to experience
either an intermittent loss of power steering assist or unintended power assist." (Source: GM)

SnapOn made a special tool to remove the bearing without having to remove and disassemble the rack.
http://public.snapon.com/a_...ments_us/ukcj147.pdf

The Rack and Pinion lower pinion bearing can fail due to faulty original bearing.
http://my.cardone.com/techdocs/pt%2022-0008.pdf

[This message has been edited by fierosound (edited 06-02-2015).]

MRBLUE87 JUN 03, 02:03 PM
GM # 7828012 interchanges to Timken DB53313. This might be what you need?
lateFormula JUN 03, 02:59 PM
That manual diagram is curious because it is titled 7. Remove and install roller bearing assembly. But in the image the bearing is noted as a ball bearing assembly.

The part number MrBlue87 provided is a roller bearing assembly that does not have an inner race.

The dimensions you provided for the destroyed bearing don't match any common ball bearing. The closest I could find is a 6200 series ball bearing (the bearing part number will include 6200) which measures 10mm ID × 30mm OD × 9mm thick. I do not find a bearing with a 10mm ID and 30mm OD that is 8mm thick. Have you pulled the bearing remains out of the rack yet? Once you do remeasure the ID, OD and thickness. It is probably a common bearing size that could be replaced with any number of bearings from different manufacturers.
fierosound JUN 04, 12:30 AM

quote
Originally posted by lateFormula:

That manual diagram is curious because it is titled 7. Remove and install roller bearing assembly. But in the image the bearing is noted as a ball bearing assembly.

The part number MrBlue87 provided is a roller bearing assembly that does not have an inner race.

The dimensions you provided for the destroyed bearing don't match any common ball bearing. The closest I could find is a 6200 series ball bearing (the bearing part number will include 6200) which measures 10mm ID × 30mm OD × 9mm thick. I do not find a bearing with a 10mm ID and 30mm OD that is 8mm thick. Have you pulled the bearing remains out of the rack yet? Once you do remeasure the ID, OD and thickness. It is probably a common bearing size that could be replaced with any number of bearings from different manufacturers.



Right on everything. Who the hell proofreads these things at GM - someone with no mechanical experience??

I've taken this apart now. There are TWO bearings for the pinion shaft.

There IS a roller bearing and seal in the upper portion of the housing to center the pinion.
They don't show the parts in the diagram, but they list the roller bearing and seal part number on Page 6.508-Group.

Then in the diagram, they only show the 10mm x 30mm x 8mm BALL bearing at the lower end of the pinion shaft.
They don't list a part number for that and again - GM uses a non-standard size (we all know about finding fuel line o-rings).

After seeing how this one fell apart and the recall information on other cars with same problem, you would NOT WANT a "factory" part anyway.

I used a 6200 series ball bearing - steering rack is fixed, probably permanently - owner is ecstatic!

[This message has been edited by fierosound (edited 06-05-2015).]

fierosound JUN 04, 09:54 AM
You guys want to have an 88 Service Manual to do any work on your Fiero...
It tells you how to reassemble the rack properly so it is centered.
(unfortunately it not always 100% complete or clear - see above post)

NOTE: a "rebuild kit" for the 88 steering rack would be:
1 - passenger side rack bushing (see Dickman's site)
1 - 6200 Series pinion shaft ball bearing (lower end)
1 - Timken DB53313 pinion shaft roller bearing (upper end)
1 - pinion shaft seal GM part# 26006299 or National part# 222028
... and of course, inner/outer tie-rods as needed

Here is how to replace that lower bearing (not covered in Service Manual)

Getting the 88 rack out is easier than on the 84-87 cars - less parts to remove.
Once I got the wheels off and the tie-rods ends disconnected, it's just the 4 bolts for the 2 U-shaped brackets.
The pinion just "fell out" if the rack because of that broken lower bearing.



I disassembled it to clean it up and make sure no pieces of old ball bearing were inside housing.
With the rack out, I was able to knock out the lower bearing outer race.



Pieces of old ball bearing and new replacement pictured below.
I used a 6200 Series ball bearing - 10mm I.D. x 30mm O.D x 9mm Wide (all brands same number)





There should have been 8 balls - I only found 3 and nothing else.
(may have been in bottom cap when I scraped crap out of it)

New bearing is seated into place (used a socket and hammer).
When the old bearing broke, this end of the pinion shaft just flopped around.
Because new bearing is 1mm wider than old bearing, slot for snap ring is partly covered.



Snap ring slot in aluminum housing is easily grooved wider with a Dremel tool.
I covered bearing with tape to avoid getting Dremel grindings in it. Here is snap ring installed.



Below is shot where you can see both bearings.

Upper end has a roller bearing and seal.
I would have replaced those if I could find the parts easily
Roller bearing GM part# 7828012 interchanges to Timken DB53313
Seal is GM part# 26006299 or National part# 222028

New lower ball bearing that was just installed is seen at bottom.
(this plastic sleeve thing can be pried off - but I was worried it may crack)



I packed grease into both bearings before reassembling the rack as per manual instructions, and reinstalling it in the car.

Reposting the diagram of how this pinion and lower bearing go together.
A nut goes on the end of the shaft and a pressed in dust cover seals the end from dirt/water.

[This message has been edited by fierosound (edited 07-18-2018).]

Michiganman JUN 04, 12:16 PM
Is it probable that this could be the cause of my 1987 hard steering? Very hard to steer.
Since I've never driven another fiero, I don't have any comparison experience. But, i wouldn't have bought a new one in 1987 if it steered as hard as mine does.
fierosound JUN 04, 02:02 PM

quote
Originally posted by Michiganman:

Is it probable that this could be the cause of my 1987 hard steering? Very hard to steer.
Since I've never driven another fiero, I don't have any comparison experience. But, i wouldn't have bought a new one in 1987 if it steered as hard as mine does.



No way for you to have this particular problem - 87 is a different rack.
Start your own thread with more details (hard to steer is too vague) on what you are experiencing.

[This message has been edited by fierosound (edited 06-04-2015).]

fierosound JUN 04, 04:39 PM
I asked Cliff to move this to How To section...

[This message has been edited by fierosound (edited 06-04-2015).]

lateFormula JUN 04, 09:20 PM
Did you use a bearing that had no dust covers on the bearing? Personally I would have only used a bearing that had covers on both sides and had removable covers (snap rings). I would have removed one cover and packed the bearing with chassis grease, reinstalled the cover and then installed the bearing into the rack.