Coil Spring compressor

[paults1]

Has anyone used a portable Hydraulic coil spring compressor? Iam ready to install the rear suspension and can't find a compressor that has enough clearence from the trailing arm mount to the upper mount. The hydraulic unit Iam looking at is at mcsdepot.com. I tried to install the springs by pushing down the trailing arms, but could not get the trailing arms lined up with the body mount bolt. I want to follow the procedure as outlined in the MB Service Manual, August 1959, Job 35-1. Then the dreaded compensating spring installation issue. Any help or guidance would be appreciated.

Regards, Paul '63 230SL
              '05 Mustang GT

[jeffc280sl]

Hi Paul,

There are other procedures in the BBB for installing just rear springs that do not require compressors.  It assumes that the axle is otherwise mounted and that a spring change is all that is required.  Then you get to the compensating spring where a compressor is needed.  Are you trying to re-install the axle or just springs?

Jeff C.
1970 280SL 4-speed

[paults1]

Jeff, Iam installing the entie rear end assembly. How can I install the springs after I have mounted the vertical hanger strut that mounts in the trunk without using spring compressors? Is the BBB the same manual that I refered too?

Thanks for your reply, Paul

[jeffc280sl]

Hey Paul,

I installed progressive springs on my car one side at a time.  I did this with center hanger, trailing arms and shock absorbers installed.  Disconnect one trailing arm at a time at the floor/frame mounting.  If the spring is installed it will be under a load so you need to use a jack or other device to lower the arm slowly after the bolts are removed.  In your case you will need a jack to lift the front of trailing arm into place after the spring has been inserted.  Look at job 32-6.  It's not too difficult a job.

Jeff C.
1970 280SL 4-speed

[paults1]

Jeff, OK, Job No. 32-6 is for the front end springs. My Workshop Service Manual is Job No. 32-5 "Removal and Installation of Rear Spring". Now, Iam going try this again:
1. Make sure the center hanger is 158mm from the driveshaft joint mounting & at a 90 degree angle from the left axle tube.
2. Jack up the assembly keeping the axle tubes horizontal & mount the center hanger. (I made an attachment for the floor jack to keep the axle tubes level)
3. Install the shock absorbers.
4. Attach the "locating cross-strut".
5. Attach the torque arms to chassis base panel.
6. Adjust cross-strut if necessary using the DIY alignment tool that is found on this website. (I made one).
Now, Job No.35-1 says install the left & right springs, ("see Job No. 32-5)". Job No. 32-5 says use the Spring (compressor) Tensioner.
7. So, without using spring compressors, & using Jeff's instructions, I should detach one of the torque arms & insert the spring, re-attach torque arm by jacking up the front of the arm, attach to chassis & repeat the other side.
The only difference here is that before I did not have the torque arms attached to the chassis to make sure the alignment was correct & I inserted the springs but could not get the torque arms centered to the chassis mounting bolt.
8. Attach the Compensating spring.
9. Connect brake lines, install brake drums, wheels.
So, 3rd time attempt will be next weekend!!

Paul, early '63 230SL

[jeffc280sl]

The Mercedes CDROM indicates the rear spring removal and installation is job 32-06.  This job makes no mention of a spring tensioner or compressor.  Send me you email address off-line and I will be happy to provide you with a copy. It appears that procedure for this job was revised somewhere along the way. Your steps sound logical but I have no experience with the axle istallation as a whole unit.

Mercedes understood the difficulty in alignment of the trailing arm to chassis mounting and they designed a cone shaped mandrel to help out.  This job is not so bad if you do one side at a time.  I used a come-a-long to assist me with the alignment and it worked out fine.

The compensating spring installation is easier if you loosen the bracket when removing and reinstalling the compressed spring.  If you do this you will not have to compress the spring as much to get in out or in place.

Jeff C.
1970 280SL 4-speed

[Vince Canepa]

Leave the compensating spring until later.  Step 5 is not necessary.  Go straight to Step 7.  Leave Step 6 until all the springs are in.  Sometimes the trailing arms are very difficult to get mounted onto the chassis mount.

To compress the compensating spring, I made a tool out of 1/2" threaded rod.  Place a large washer at the left end, in the eye on the differential (you might have to grind one side to get the rod centered in the eye).  Make a cross bar out of 1/4" x 1 1/2" flat bar for the right end of the spring.  Remove the bolt on bracket on the left axle tube.  Place the spring against the eye, assemble the tool inside the spring, using the tool compress the spring enough to reinstall the bracket.

Vince Canepa
1967 250SL
113.043-10-001543
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