"Throttle Jump"

[staciataku]

I've got a '74 Bronco that I am resurrecting - it's been sitting for a while. It was supposed to be my project truck for 4-wheeling, but I have not had the time/$ to get it where I want it. I have recently started working on it, and I have a strange problem - When I try to accelerate gently (in 1st, 2nd or 3rd) it feels like the pedal hangs up at the beginning of it's travel, and then all of a sudden lets go causing the truck to jump. The strange thing is that in neutral I don't feel any hang up and I can feather the throttle just fine. It only seems to happen when the clutch is all the way out and I'm just trying to accelerate smoothly with the gas. I feel like I can avoid the issue by riding the clutch, but I'd like to figure out why it's doing it. I don't see anything wrong with the linkage and I'm not sure what's up. Any ideas? Also, the truck will shudder pretty bad while accelerating sometimes - I think that could be the flywheel. Could there be any relation between the two?

Thanks in advance,

Brendan

 

[Bully Bob]

- When I try to accelerate gently (in 1st, 2nd or 3rd) it feels like the pedal hangs up at the beginning of it's travel, and then all of a sudden lets go causing the truck to jump. It only seems to happen when the clutch is all the way out and I'm just trying to accelerate smoothly with the gas. Also, the truck will shudder pretty bad while accelerating sometimes -

Brendan

Just a thought...

Take a look at the motor mounts...& a closer look at the linkage.

The motor may be lifting just enough to cause a bind on the linkage... especially the part on the firewall.

This may be causing the shudder as well @-) B)