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Takeoff Judder - Worn throttle bushing

Since buying the car a couple of months ago I have been slowly going down what appears to be a familiar rabbit hole of trying to improve shifting and clutch feel. I've done the normal things, omega spring, clutch cable, new shifter bushings, new shift joint, trans lube, pedal bushings, etc.

All have made small incremental improvements, however I still had a really annoying takeoff judder that only seemed to be managed by revving a little higher than needed and slipping the clutch a bit more than I'd like. If you didn't manage the judder by slipping the clutch, it would kind of go into a resonance and get worse, sometimes bucking fairly severely...

Then a couple of weeks ago I was replacing the throttle pedal and found the urethane bushing for its lever on the pedal box was completely worn out, allowing the lever to flop around pretty easily.

I replaced the bushings, but didn't think too much about it. The next time I drove the car, I was surprised to noticed that the takeoff judder was nearly gone. I think the pivot lever was moving under the inertia of acceleration and initiating the judder...

So, an unlikely source seems to have cured my problem. Good thing, as my next item was trans mounts...heh


Old 10-10-2018, 04:45 PM
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How are your motor mounts? Just asking. My SC had pretty much the same problem, then I found that my circa 1983 (exactly) needed replacing. Now, I don't look like a rookie (even though I've been driving a standard car since 1969) in first gear. . .
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Old 10-10-2018, 06:57 PM
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Haven’t inspected them yet...they’re on the winter list though. I was saving them for last because the car only has about 56k on it and was rationalizing that they wouldn’t be worn yet...still possible though I think.

Last edited by Quasimoto; 10-11-2018 at 01:24 AM..
Old 10-11-2018, 01:22 AM
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Can you post your model year or embed it in your signature?
Glad you found the source of the judder.
I think that bushing may be the same one used for the throttle linkage on the bell crank mounted to the transmission as well - at least I think it was for my '87.
Since you're already aware of the rabbit hole, you might look at the rest of the bushings on the pedal cluster as well as any others in the path of the throttle linkages - there's another on top of the engine deck (along with 2 springs that sometimes give up the ghost) also on the 3.2's.

someone came up with a pedal bushing kit in bronze for the 915, but not the 3.2's which is a mix of plastic/nylon and bronze. For the part you're showing, I think there is a bronze one available. Checkout 901 423 253 00 M105 FYI if you think you'll need one for the bell-crank.

And just a comment on the mounts and your low mileage (nice btw), sometimes the mileage number doesn't matter so much as the age - motor and tranny mount refresh might be helpful.
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Old 10-11-2018, 05:58 AM
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Thanks for the tip! I have an 84...

Luckily I had preemptively ordered the bushing kit from our host, so they were on the bench when I needed them. All in the kit are bronze. Will install the others over the winter downtime...

FWIW, the urethane bushing appeared to be degraded by age and atmosphere rather than wear.
Old 10-11-2018, 07:08 AM
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