Steering wheel (up/down) plan

[Tday]

Sorry for a double post here---I put this on the backdraft boys site but am new enough that I don't know where most advice givers hang out.

I've been reading threads on steering play and shakes and general suspension issues. Have tightened the set screws on column, tightened slightly the pre-tension on the rack to get out back/forth steering wheel play. When I hit bumps or the road is a little rough, this car really shakes and rattles. Part of it is the steering wheel which can move up/down or side/side by 1/4 inch.

Haven't taken a look at what's holding things together but thought I'd ask if anyone has had this and suggestions.

I'll probably also want to think about front suspension in general with road use being primary use. Anyone have a good suggestion on shocks/springs...or perhaps mine are just worn (1400 miles?) I'd like something like on my mr2 years ago...gas shocks that hugged the road.

Also, anyone done any frame stiffening other than BlackBDR? or do you think my car sounds like it's got its own problem, not a frame stiffening problem.

Thanks, Tom

[SkipB]

Tom,

Which wheels set up do you have? 15 or 17". Backdrafts are pretty sensitive to proper wheel balance and in some cases alignment (what little you can do!) But I have found on the 15" set up, the cheap BFG or Goodyear tires are usually to blame. Neither brand is very round! Get them balanced and on some tires even "truing" will help. Or replace any tire that is just too out of round. I hear this is not too unusual. On the 17" set up, the tires are so big, that the balance and alignment are critical. Once that is accomplished, it should be much better or OK. Make sure the rest of the front end/suspension is secure as well.

Early cars like mine (#90) had some sagging spring issues. I am not sure at what chassis number the new better springs were factory installed. All I know is Backdraft sent me new springs and things are much better now. Unless your car had the old springs, 1400 miles is certainly not enough to wear anything out!

Try the above fixes first before you spend a bunch of money on frame stiffening. I know John and he loves what it did to his car. But, without good balance and alignment, it would be a waste of money.

In any case I originally had balance issues (15") wheels. I had them rebalanced, added hub-centric rings to the wheels (aids in centering the wheels on the hubs), and had it aligned, and corner weighted. Problem solved.

SkipB

[Tday]

Skip---thanks. Good advice all around. Here's what it sounds like.

I have the 17" wheels and the car, on the highway is really straight and true at any speed through 100 anyway. Not a shake or issue. I will go to an alignment shop and get it done so I know what everything is set at. We have a hunter balancer down the road so I'll do that too. That's good money spent, I figure, but I don't think that's the problem since it drives well at high speed.

Next step will be to check out spring/shock combinations...or maybe they're thought of separately, choose a spring set, then choose a shock. Seems like there must be some good road combo for the rough road northeast but I'm not sure what that would be. The bilsteins seem like racing shocks so it seems like the wrong move. Don't know what the other choices are. Anyone? Koni make something that works well? Springs? I'll but the updated ones on unless I hear other choices for street.

And how about the steering wheel movement up/down by 1/4 inch? That usual?

Then, when that's done, if it shudders still, I'll look into frame stiffening. Is John the only one who has done this?

Thanks,
Tom

[Gatorac]

The steering wheel movement is not normal. Does the steering wheel and column move? If so, right behind the dash is a mount for the column. Check to see if that's tight. If the column is not moving and the wheel is, I would suspect a failed bearing in the column itself.

[Tday]

Thanks Jim...

[jp65cobra]

Tom

There is a thread on this site about frame stiffening done to a car here in San Diego.

Chassis Stiffening Kit

I have used the shop mentioned and they do good work.

John

[Bailey]

Like Jim said.
Check to see if the whole column is moving, or the steering shaft within the column. There is an upper and lower bearing, both BMW parts. I have replaced both. I believe the carriers were plastic, and with some wear and vibration caused by improperly balanced wheels, it might be what is going on.
Next the cowl brace and windshield are bolted in. Verify that ALL the bolts are tight. I check mine every few months. Even with lock nuts, they seem to loosen up.
Also follow Jim's advice again. Check the U bolt clamp that secures the column under the dash.
Keep us posted,
Richard Bailey

[Tday]

Thanks...great idea about the windshield and cowl brace...they're definitely rattling. I'll check the steering column bearings, good to know there's a wear point in them.

Tonight I pulled the front wheels and had a look at the shocks and springs. I have the 12mm springs and they're set at 57mm between bottom of the spring screw to last thread on shock. That looks right in terms of wheel fitting the fender when driving...not sure what others are doing. The right front shock is oily and dirty, so I think it's leaking and gone south.

What's a good replacement shock for street use? (Don't mind a stiff ride.) and are the 17mm spring coils good for street driving?

Thanks,
Tom
PS: also found that the header from #8 cylinder (back right side of vehicle) is very close to the foot box (1/8") so there may be some banging on the fiberglass too.

[Tday]

OK, here's where I am in the process. Thanks for all the tips. It's really helped out a lot. Since the tires are balanced and smooth on the highway, I focused on general loose fit/finish items first.

I tightened allen screws or nuts on the windshield, seat runners, and doors. Also adjusted the hood latches since there was some play there too (that made a huge difference to have them pull the hood snug to the rubber bumpers. Put some electrical tape (for now) on the door latch posts. (any suggestions?) Pulled the wheels and checked the shocks and coil over springs...set the fronts at about 2 1/4 inches from bottom of threads. Tightened the pretensioning on the rack so there isn't any back/forth steering play.

Man, what a difference. Like night and day. I have the 12mm coil over springs in the front which seem pretty good for street driving now that the car isn't shaking.

I see that I have up/down play in the steering column---the column doesn't move, but the shaft moves up/down within the column. I'm told that requires replacing the column bearings which apparently have a plastic bearing race.

A few questions: What is the part no/mfg for the two bearings and where might I get them?

Does the column pull out if you take out the cross screws just above the top u-joint, take off the tops to the bottom 2 supports, loosen the two set screws to the top support, and loosen the u-bolt under the dash?

Are the bearings visible and easy to pull from the column?

Thanks, Tom

[Bailey]

Tom.
The part# for the bearing assy on the BMW box is 32-31-1-158-835
Reg has them too if needed
You will need 2. What I did was leave the outer column in place, and remove the steering shaft. The two bolts connecting the shaft to the lower u joint need to be removed. The steering wheel and turn signal need to be removed, and the set screws at each end loosened up. This should allow the inner shaft to slide out, towards the driver.
Patience is your friend, this is a job to be done when you have plenty of time. Reassembling the bits properly can be a bit tedious, but when it is done it will be right.
Good luck,
Richard

[Tday]

OK, finally got this one done. The BMW bearings have a plastic race, so no surprise they developed play. I ended up pulling the steering column complete with the steering shaft intact so I could figure out what was going on. The new bearings snap in place and with a little synthetic grease on the shaft collars at the end...things go together easily. You do need a steering wheel puller and 5mm screws to attach the puller to the steering hub. Should be worth it, now that I've got the front end smooth as silk with the new gas cartridges.

[Bailey]

Tom,
Are things back together? Better?
Cheers,
Richard

[Tday]

Yes, for sure...there's no up/down play at all...tight as a drum! Can't drive it until I get the pipes back on as I'm still diddling with the sound (and of course no snow on the roads...today would have worked.) Tom

[Bailey]

Excellent, one less thing on the list