TheSamba.com :: View topic - Clunk on Accel/Decel-

Wed Nov 05, 2008 10:46 pm

Greetings..

I have a '73 thing. I recently raised the back end a spline or two. I have 930 CVs.

Recently, A 'clunk' has developed that has me concerned. If I am in gear, and apply the accelerator without touching the clutch, I get a clunk, and when I take my foot off the accelerator, I get another clunk. I feel it in the floorboards, and seat, but not the shift lever. My first thought was transmission mounts; I got under the car and checked them out. Everything looks good.

The transmission is a fresh, stock transmission from AZ transaxle.

I checked the CV bolts, they are all tight and everything looks good.

I do have a CV that makes noise when I make right turns, but the CVs are fresh, and are nowhere near max angle. I did go with 930 cvs because the torsion crank from the previous owner was killing the Thing CVs. If a CV was going, would I get grindy noises, or a single clunk on accel/decel?

I noticed when looking under the car, that the bolts that secure the trailing arms to the spring plates had been sliding on the springplates... I guess they loosened back up after I bolted everything back together. When I discovered the slide marks today, I wasn't able to torque the bolts to 80 f/lbs, because I didn't have a socket that was short enough to allow me to get the torque wrench on the bolts. I put a box end on them, and horked them down smartly. This weekend, I'll get them torqued properly.

So, I'm still getting the 'clunk'. What else should I be looking at? If my torsion arm bushings are worn, will the torsion bars move enough to hit the covers, and make a noise?

Where can I get the proper washers for the spring plate bolts?

Anyway, thanks in advance for any help. This is my daily driver, and I'm getting a little freaked out.

Thu Nov 06, 2008 5:21 am

Although it's logical to try and tie this to something that you recently changed on the car, it may in fact be a totally unrelated problem.

So far, you've checked everything that I would have initially recommended. You say that you DON'T feel the clunk in the shifter. That seems to rule out the engine/transmission to me but you should check the engine bolts/mounts anyway. You already checked the transmission mounts.

When you feel the clunk does it sound/feel as if it's coming from the rear, from "all around" or from the front?

Thu Nov 06, 2008 8:39 am

EODinert wrote: I noticed when looking under the car, that the bolts that secure the trailing arms to the spring plates had been sliding on the springplates... I guess they loosened back up after I bolted everything back together. When I discovered the slide marks today, I wasn't able to torque the bolts to 80 f/lbs, because I didn't have a socket that was short enough to allow me to get the torque wrench on the bolts. I put a box end on them, and horked them down smartly. This weekend, I'll get them torqued properly.
...
Where can I get the proper washers for the spring plate bolts?
I'm pretty confident that this is where the "clunk" is coming from. Those bolts hold the trailing arm to the spring plate. Under accel or decel, the wheels push directly against them. If they're at all loose, I can imagine that they'd slip and clunk against the forward holes under accel, then clunk again when you hit the brakes or let up on the accelerator. They've probably made handling pretty lousy too (wandering around the road as they shift).

You're looking at getting them fixed anyway, so cool! If I'm right, getting the right washers on there and getting those bolts torqued properly will likely make this noise stop. If not, well, you had to fix that anyway :D

Fri Nov 07, 2008 12:51 pm

Found it.. Nose cone mounts broken. Yay.

Thanks.

Fri Nov 07, 2008 12:57 pm

EODinert wrote: The transmission is a fresh, stock transmission from AZ transaxle.
EODinert wrote: Nose cone mounts broken.
Didn't see that coming. Sorry to hear it - I've been there too many times (busted my transaxle twice in the last year). Just when you think you've got the part square and you're sure this part will last another 20 years, you're reaching for the wrench set again with a deep sigh.

Fri Nov 07, 2008 7:44 pm

Exactly. Last thing I thought I'd be working on. I've got a '61 I've got pan off right now, my son and I are mostly restoring. I'd much rather be fitting my new sunroof cover, or welding my new WW pans in.

I got it mostly fixed today. I had one of those transmission strap kits that the previous owner had on the car. Only the bottom bolt hole on the nose cone mount was broken, so I tightened the remaining bolt, and installed the strap kit over the front of the transmission. This will give me time to find a nose cone, and I will install the nose cone at my convenience.

I really didn't feel like taking my whole car apart today, glad I didn't have to.