Azir Khan

I checked the ride height last weekend and it measured one inch less then specifications in the front. I got the special tool today and tried to adjust the "adjustment nut" but nothing happens ! The nut simply turns but will not move up or down ! it appears that the threads of the "adjustment nut" are not engaged with the threads on the shock absorber. But is this possible ? if the threads come off, then whats securing the adjustment nut on the shock ?

Thanks for your help.

Azir
87, Auto, Black/ Tan. 92K, 17" Cup 1. http://www.928registry.org/1987-928S4-0432.htm

ErnestSw

It takes 8 full turns of the nut to move your height 1cm.

Don.

Take a pencil and make a mark right below each adjusting nut to get a baseline. After one full turn of the nut there should be noticeable movement.

-Don

Normy

It may take several turns to notice an effect; I did this recently and at first was concerned that my shocks were "stipped", but in the end it worked.

Make careful note of that ratio posted above: 8 turns/cm! I initially brought my ride height WAY high. My mom walked by enroute to the garage, and she even stopped and said "Is it supposed to look like that?" LOL!

Normy!
'85 S2 5 Speed

Azir Khan

I marked the original position with a marker and counted three full turns but did not register any axial movement of the nut ! Unless I am missing some thing I think that the threads are either not engaged or are stripped. I guess a complete dismantling of the "coil over" is next.

Azir. http://www.928registry.org/1987-928S4-0432.htm

SteveCo

Azir;
I recented adjusted the ride height on my car as well. Couple of things to keep in mind. At least on my car ('85 with Boge shocks), the adjusted "bolt" (the part that is directly attached to the shock) is not actually restrained by anything other than friction from weight of the car. It slips down over the shock tower and is sort of wedged into position, so it is possible that the "bolt" can simply rotate when you turn the adjuster "nut".

This happened to me when I adjusted the "nut" too high and ran it off the end of the "bolt" threads. In trying to rethread the "nut", the lower portion of the adjuster would simply spin. I was afraid that I had sheared off some restraining mechanism for this device, but a quick check of PET indicated there were no fasteners or such. I was able to counterhold the "bolt" portion with a flexible strap wrench and rethread the adjuster nut (turned it counter clockwise a few times, then slowly clockwise to start it on the threads again), FYI.

Your adjuster mechanism might be seized or just in need of lubrication, so apply some penetrating oil to the adjusted threads before you start the adjustment process. I found mine turned very easy even without lubrication, but I doubt this is the norm. Maybe a few applications of penetrating oil over a couple of days will help your situation?

After realizing one can adjust too much, I now know it is a good idea to monitor your progress. As ours have mentioned, a pencil mark on the shock tower or lower adjuster threads works for this. I also kept an eye on the amount the spring was compressing. I simply measured from a fixed part on the body at the upper spring mount to the edge of the lower spring mounting cup. I used this method to ensure that both sides of the car had exactly the same adjustment while the car was in the air, then fine tuned things after a road test and measurement as per the factory settings on the suspension locations.

Regards,
SteveCo in St. John's

GlenL

SteveCo is right in that it sounds like the nut is frozen to the collar. This may not come loose. I couldn't get mine free and I had the whole assembly off the car and apart. Soaked it but didn't torch it. Didn't take it to the machine shop, either. Luckily, it was all the way down, I wanted it lower and when I measured the resul the height was exactly where I'd hoped to get it: 155mm. Gotta drive it carefully on the street. Parking lot entries and RR tracks are attracted to my skid plates.

Advice: Try some penetrating oil and maybe some heat. If that doesn't work you'll need to pull the shocks to fix it and maybe put it new/used parts.

Niklas Kampe

Azir,

Did you figure out what the problem was? I am having exactly the same problem now. Adjustment on the front left shock worked fine, but on the front right shock the nut just spins but doesn't move up (and it is much stiffer to turn than the nut on the left). Looks like the nut is very low, is it possible that it has been screwed so low that it has come off the threads?

Best regards,
Niklas Kampe
928 S4 1987
Finland, Europe

SteveCo

I don't think it is possible to screw the nut so low as to unthread it, but I am not certain about this. If this could happen, I would think the spring would not be retained on the shock tower and would flop free.

The only advice I could offer on this would be to thoroughly clean the entire upper shock tower and spring assemble, particularly the parts inside the spring itself. Then douse the adjuster and lower part of the spring assembly in penetrating lubricant. You could also try slightly heating the adjuster nut. Don't overdo this and make sure you wash off any lubricant before you try this...would not want you to start a fire!

In the end, it may be more expedient to simply remove the shock & spring assembly, dissassemble it to get at adjuster and then get it working again. The infor on this procedure can be found in the archives or on Greg Nichol's site. Alot of work, to be sure, but I am more convinced than ever that a properly adjusted ride height is critical to handling performance and longevity of the car in general.

Regards,
SteveCo in St. John's

Niklas Kampe

Thanks for the info, SteveCo. The workshop manual says that if the nut is screwed too low, the lower spring seat will no longer make contact with the nut but instead with the top end of the threads. But it doesn't say if it can be screwed low enough to unthread it...

I have sprayed some penetrating lubricant on the assembly and let it soak overnight. I'll try again today, hopefully with better success.

If it still turns but doesn't move up or down, what does that mean? Does it mean that the thing with the threads is rotating together with the nut?

Best regards,
Niklas Kampe
928 S4 1987
Finland, Europe

SteveCo

Niklas;
Yes, I would think it means the nut and collar are seized together. On my car the nut is aluminum and the collar is brass and there was factory anti-seize compount on the threads. This would indicate the potential for galvanic corrosion, but I would not think they would seize really badly.

GlenL had the same issue (from his post above), so he could probably give you a better idea of the step to remove and remedy this. Essentially it is the same process as removeing and replacing a spring or shock...not difficult, but not easy either.

If you have access to the electromic parts catelog, you can see the pieces and how they fit together. The big item is compressing the spring to allow removal...not for the faint of heart...you could remove the suspension part from the car and take it to a mechanic for dissassembly/reassembly of you don't want to tackle this yourself. I know many people do it this way.

Regards,
SteveCo in St. John's

SteveG

Ernest/Normy: I believe it is 8 turns/INCH. That worked for my OEM shocks. YMMV.

SteveCo

My experience mirrors SteveG's as well.

8 turns = 1" spring compression (or ride height lift) = approx. 2" of body lift.

Regards,
SteveCo in St. John's

Azir Khan

UPDATE !!

First off, let me thank all of you for your advise. I ended up dismantling both front spring/ shock assembly and found that the adjusters were frozen due to corrosion. I took the components to a local shop who managed to free the drivers side after an overnight soaking and heat treatment, but the passenger side did not. He eventually destroyed it by applying too much heat and warped the component (careful who you take these component to!). Eventually ordered a used part from 928 Int. (these Guys are great)

I started off with the FL=152mm & FR=154mm. Initially set the front to 180mm but soon lowered it to 170 as it just did not "look" right at 180mm. I found the ride has improved somewhat and the steering has become slightly lighter. Now I have to find a shop to align the car. Thank once again for all your help.

Azir.

Gregg K

Antisieze. Comes in a can. It's a silver paste. It's a must use, in my book. Coat everything liberally.