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Throttle not returning

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ekamm

ekamm

Jedi Warrior
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Recently my tr3a has been idling high, when I lift the accelerator peddle with my foot it drops idle back where it should be. Also if I lift up on the linkage at the carb it will idle back. As far as I can tell all springs are still there I have oiled any spots that appeared to be a possible culprit. Looking for some ideas of what to look at next.
 
Eric - bravo to you for figuring out you can "fix" the problem by lifting the gas pedal. Same problem with mine.

On mine the problem is a worn bushing on the linkage as the pedal connects through the firewall. I feel the fix is more trouble to me than just living with it, as that bushing is *really* tough to get to, at least for me.

I've learned the highly-advanced technique of lifting that pedal with my toe. Required a private trainer, but I finally mastered the art. :smile:

Tom
 
weak return spring behind the second carb on firewall, ball connectors overly worn and hanging up, sticking jey assembly.
I'd experiment with a slightly stronger on new spring first.
 
Eric --
I think ALL TR3s do that. I do the toe thing too, sometimes.
 
After I went through all the linkage possibilities, I finally figured out that it was the front throttle bushing causing the problem. Not by binding, but by being worn enough that the throttle plate would actually drag on the bottom of the carb bore.

Rebushing the carbs made the problem go away.
 
BTW, the return springs on the H6 carbs are adjustable. Loosen the clamp and twist it, hold it there while you tighten the pinch bolt.

But the extra tension will make the bushings wear even faster.
 
I have that and have perfected the foot trick. On mine I think that it is wear in the bellcrank pivot. Has anyone found a source for them as the big 3 seem to show it as NLA?
 
I did my own throttle shaft rebush. Did mine the hard way, using a drill press to try to line up the bores, which worked out well for me. Only had to ream the first one, the others lined up perfectly.

But I've since seen this tip which looks a lot easier (and safer).

Sorry, don't have a source for the pivot. But it can be pretty sloppy without hurting anything, as it's all under spring tension. If you wanted to, you could probably clean it up by finding a piece of thin wall brass tubing (like sold at hobby shops) to fit over the pin, and then reaming the pivot to fit over the tubing. Or, if it's too far gone for that, use SS tubing over the pin and put a brass bushing in the pivot.
 
If you're going to change the firewall pedal bushings, you might consider what I did. I got the self aligning bushings from McMaster. I had to make one part for the assembly, but it has worked out great, and is engineered to be replaced very easily if need be.
 

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Art, that looks slick! I'm going to have to remember that!
 
So this morning, had a hard time getting full movement thru the accelerator linkage, and thought I'd gotten bitten reading this thread. Hmmph, gotta replace the bushings; turned out to be something different:

IMG_1127.jpg


Loosening pivot bolt, rubbing up against ARE carb shield, (might be a little hard to make out). Tightened, regained full movement, yahoo! Next time carbs are out, a little Dremel work will take give me a little more room...
 
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