CSX7070 Rear Suspension Rebuild

[CSX7070]

Hello All! I am getting ready to remove the rear suspension from CSX7070 to inspect and try to diagnose a clunking sound from the rear when making a left turn.

I suspect the rear leaf spring has come loose (like the front did) and the 4 bolts need to be replaced. I suspect the half shaft is hitting the opening on the rear frame.

I saw a trick from the 60's putting key stock on the side of the spring on the top of the perch, then tack welding the key stock to the perch to keep the spring from moving on the center pin.

I will be posting progress photos and if anyone else with a CSX7000 or 8000 series car with leaf springs has had this same issue - it would be great to hear from you.

I FIRST made custom posts for my lift to stabilize the car when on the lift. this was completed this weekend and they work great! My lift is custom made to be able to reach the 3" tubes. Standard lifts do not work or reach.
Even now...the arms are at almost full extension and it seemed a little unstable due to the flat lift pad on a round tube.

Safety first before banging around to remove the entire rear suspension. I also may have a leaky fuel cell....I will be checking if it is or if it was just over filled at our last cruise.

[CompClassics]

Check the build date on the fuel cell, racing organizations recommend new bladders every 4 years, check your manufacturers recommendation.

[1985 CCX]

Agreed, my bag started leaking at 7 years. Had an alloy tank made, no more leaking. John is right, replace...

[Allan A]

I had a clunk when I was on the freeway and hit a bump. It was the spring hitting the upper frame support at wheel well. Kris cut out the small square tube and lifted it higher.

Cheers,

Allan

[CompClassics]

Yep, I had forgotten about the SAI spring issues.

[peterpjb]

I checked all these issues at my car after I purchased it with 13.000 mls:

the clunking sound from the rear when making a narrow left turn comes from my limited slip diff, it works so well that it loosened my left rear knockoff, so use safety wires

we tested the SAI aluminium fuel cell with pressure and it was fine, the outer box went to the dumpster,

the rear uprights, control arms and wheel bearings were all fine, we only changed the brake caliper to original spec,

the rear leafspring was to weak, we strengthened the springs and the car went around 1" higher at the rear

the front uprights were not original specs, so we changed the uprights, control arms, front leaf spring, bearings, brake caliper etc to new original spec parts
but that was the original reason to change the parts, they all worked fine

[CompClassics]

I have front and rear CSX7000 and CSX8000 Series Continuation Cobra uprights if anyone needs them, includes the front steering arms and upper pivot joints.

[MAStuart]

Could you post some pictures of them? What would they sell for? Also why do they get replaced and with what? I guess I would just like to see what the stuff looks like on those cars.

[CompClassics]

The rear uprights are formed sheet metal with a machined from billet bearing area and an adjustable spring mount that allows for camber adjustments. The front upright are forged lower castings with a pivot bearing for steering and a spring mount that allows for camber adjustments. The front steering arms are look to be machined from billet steel. I will post photos when I get a chance.

The reason for replacement was to replace these parts with original specification parts.

[MAStuart]

Thanks for posting. Looking forward to the pictures .

[1985 CCX]

Might add the SAI clunk frame pic?
May help others in the future.

[CompClassics]

Another reason for the clunk May be the upper chamber adjustment cam bolt adjustment. The camber adjustment bolt to the spring eye was not particularly well thought out. The camber adjustment bolt and the spring pivot bolt are one and the same, if you don’t tighten the bolt enough it will not hold the camber setting, if you tighten the bolt to much it pinched the spring eye and causes the spring and the upright to bind during travel creating wear at the thrust washers and the spring eye bushing. Eventually the wear turns into slop and you lose Your camber adjustment.

Here are the photos of the right side rear and front upright......

[patrickt]

Originally Posted by CompClassics

...if you don’t tighten the bolt enough it will not hold the camber setting, if you tighten the bolt too much it pinched the spring eye and causes the spring and the upright to bind during travel creating wear at the thrust washers and the spring eye bushing.

Dang, I hate it when you have to do something just right.

[Tjd]

There should be a sleeve on the upper bolt that goes through the spring on the front upright so when you tighten the eccentric it tightens against the sleeve not the spring if it’s binding against the spring the sleeve is not there.
Tom

[CompClassics]

What I was trying to point out was the fact that you couldn’t get it “just right”, it was incorrectly designed. It would be like putting an object in a vice and expecting to be able to move it freely.

[patrickt]

Originally Posted by CompClassics

What I was trying to point out was the fact that you couldn’t get it “just right”, it was incorrectly designed. It would be like putting an object in a vice and expecting to be able to move it freely.

Well that's more like it. Not only is it designed to be just wrong, it's really easy to get it that way too.