Trailing arm screw installation

[IXLR8]

Hi--

I removed the trailing arms on my 230SL to replace the rubber bushings.

All is well.

Now, trying to reinstall the arms, I have spent about 9 hours getting the first three big screws replaced, and I have stripped the fourth one.

When the arm is not in the bracket on the axle, the screws twist in and out of the pivot pin easily and smoothly.

When I mate the trailing arm up to the bracket, I can't seem to get these screws lined up.

I have appropriately mated the trailing arms as Right and Left.

I have tried to get the pivot pin exactly centered in the axle bracket mounting holes.

Grease and/or oil on the threads seems to make no difference.

Is there a simple trick to get these screws into the pivot pin?


Thanks in advance for any help.

Joe

[jeffc280sl]

The trailing arm bushing is not quite centered on the cone that protrudes from the body.  I used a nylon strap come along to help move the axle in the perfect position.  You can buy this item at Home Depot and they are often used to strap items together on a roof rack.  It has a ratchet type mechanism to help create just the right amount on tension.  Secure one end around the rear axle and then hook the other end to heavy bracket that holds the tranny.   Gently ratchet up tension to move the axle in place.

Here is a pic

[IXLR8]

Hi Jeff. 

I'm not that far yet.

I'm still trying to put the large screws into the pivot pins.

Thanks for the advice for when I get to the next step--good tip!

Joe

[jeffc280sl]

Sorry, I read your note too fast.  You are at the other end of the arm where it mates with the axle.  Did you replace the rubber bushings?  I think the rubber bushings can be installed a little off center with the way the rubber rests against the trailing arm.   This may cock the the threaded shaft a little so its hard to thread the big bolts.  I would try to get one side started and then use a big pipe wrench to align the trailing arm and bolt.

[ctaylor738]

I think I have an extra large screw.  PM me if you need one and I'll go look.

[ja17]

Hello Joe,

Replacing these rubber bushings is normally done when the trailing arm is unhooked from the front chassis mount also .  This will allow you to move the arm to align and start the large short bolts at the axle/trailing arm connection. Re-connection of the front chassis mount can also be a challenge. The factory has a special "mandrel" tool I made one and it helps a lot. Other home made procedures will work also.

[IXLR8]

Hi--

Thanks to all for their helpful tips and to Chuck Taylor for his kind offer of a replacement part.

Here is what I found out:

The gussets welded to the axle MUST be PERFECTLY perpendicular to the threads on the pin of the thrust arm.

The holes in the gussets are sized the same diameter as the screw, and the gussets with their interior welded-on spacer are about 1/4 inch thick.

If these gussets are not perfectly aligned, the screw does not line up with the threads on the pin. Mine were somewhat twisted, and that is how I ended up with cross-threading and stripping of the threads.

As the old song says, "Little Things Mean a Lot".

Joe