Quiz - what do you figure happened here?

[sunlion]

See photo. Hint - I would start the car and it would rev to 6K rpm and stay there!!! Good thing in happened in the driveway, not on the road.

[steely]

hard to make out - is this behind the pedal cluster? I think I recognize some bits but can't figure what is in the tunnel side there. Clutch pedal switch?

[dipso]

The bell crank melted?

[TRE Cup]

A) you did not have the pedal board in the car or B) you did not have the full throttle adjusted so the pedal hit the stop (white nylon bolt on early cars. The back of the later pedal has a stop that should hit the pedal board at full throttle, not after.

So.. When you hit full throttle, you actually passé beyond and bent the bell crank into the tunnel, bending it to instant " cruise control"
Lucky you did not have an accident

[sunlion]

steely - it is behind the pedal cluster, the bronzish part is the accelrator reverse plate. The outcome what what I mentioned above - stuck at 6k RPM!!!! The other question is why did this happen? What caused the part to fail?

[steely]

jeebus dude - glad you found that - was it what TRE suggests? (
you may have been typing at the same time.)

[jrbennett]

Originally Posted by sunlion

What caused the part to fail?

Originally Posted by TRE Cup

A) you did not have the pedal board in the car or B) you did not have the full throttle adjusted so the pedal hit the stop (white nylon bolt on early cars. The back of the later pedal has a stop that should hit the pedal board at full throttle, not after.

So.. When you hit full throttle, you actually passé beyond and bent the bell crank into the tunnel, bending it to instant " cruise control"
Lucky you did not have an accident

x2

[Mr9146]

Originally Posted by TRE Cup

A) you did not have the pedal board in the car or B) you did not have the full throttle adjusted so the pedal hit the stop (white nylon bolt on early cars. The back of the later pedal has a stop that should hit the pedal board at full throttle, not after.

So.. When you hit full throttle, you actually passé beyond and bent the bell crank into the tunnel, bending it to instant " cruise control"
Lucky you did not have an accident

He's not the first, and he won't be the last...

[RWebb]

This has all happened before

And it will all happen again.

[rattlsnak]

Yep, that happened to me before. Scared the crap out of me.! Luckily I had the smarts to turn the key off before I crashed into something!

[sunlion]

I was just starting the car the morning after I bought it. The accelerator reverse lever got stuck in the tunnel. Nothing had been modified. Why did it fail? The push rod attached to the accelerator pedal pushes on the reverse lever not straight back but at an angle. It the cable moves freely the lever will go straight back. If the accelerator cable does not move freely, then the reverse lever has torque applied to it based on the direction which the accelerator push rod moves. It pushes the lever toward the tunnel where it gets stuck (see photo.). Why doesn't the accelerator cable move freely? Well, this is a '76 912 which the PO converted the injectors to dual Webers. He connected the center throttle cable arm horizontally at the carburetors instead of vertically where the cable attaches so a lot more force needed to be applied to move the arm via the cable and pedal and the cable did not move freely. This then torqued and bent the reverse lever at the pedal cluster to where it got stuck in the tunnel. Thank goodness I was in neutral in my driveway. This could have been disastrous!!!!!!!

[77TARGAV8]

Buy the rennline floor boards, they look cool and that will not happen again. They are aluminum, not wood like the originals.

[steely]

sunlion - did you have a floorboard installed? (see post #4)
It is meant to prevent too much forward travel of the pedal/ and your foot from stressing the linkage (among other things).
if the PO modified stuff down there, you'll have to make it right.

Post some pictures and make plan- you'll get some great advice.

[sunlion]

The floor board was installed but it is a replacement one. The original was rotted. I removed the floor board for the investigation. I have to look at the pedal to see if the stop described above exists. Have not been able to work on the car since I posted initially, job gets in the way.

I am planning to remove the pedal cluster and refresh it. The bent part will be replaced. Other than brass bushings, are there other upgrades available for the pedal cluster on a '76 car.

[TRE Cup]

ok- can you post a pic of the back side of the gas pedal? We need to see if its early or late style.
If early style, then your replacement floorboard does not come with a throttle stop. The throttle stop should have been transferred from the old board. If that is long gone, your can fashion one from some large od washers , a 10 mm bolt and two nuts.
Some one here can help you by posting pics of their stock pedal board so you have an idea where to drill a hole in your replacement floorboard.

You mention that the pedal was depressing the rod at an angle to the bell crank lever. That means that the bell crank lever was either already bent to begin with. so just a matter of time before it went too far and got stuck . OR the hinge at the base of the gas pedal was broken allowing sideways movement. Again, in either case, pushing the accel rod , and hence the bell crank lever, beyond its intended range of movement means the lever can get stuck under the edge of the tunnel sheet metal

[sunlion]

I'll get pictures up as soon as I can but likely won't be until tomorrow because of work. I do have the old floorboard which I'll look at closely. I would be helpful if someone can post a pic of the throttle stop and the old vs new style pedals.