The Stovebolt Site Forums The Shop Area Engine Shop Easy Fix? Carb Throttle Rod Too Short

Seems like every time I fix one thing, two more pop up!

My '54 3100 235 Rochester B didn't have a carb insulator, so I installed one under the carb. But now, the carb rod is too short. Any easy way to lenghten it about 3/4 inch? If not, I'll try to buy an original carb rod.

The rod is not like the one shown in the '54 Assembly Manual. It does not have the bend that goes through the hole on the carb throttle lever. Instead, the top of the rod is threaded and has a tip screwed on that goes through the carb throttle lever.

Carb rod in Assembly Manual.

Threaded carb rod with no carb insulator.

Threaded carb rod with 3/4" carb insulator. Accel pedal is only about an inch off the floor.

Tip that is screwed onto threaded carb rod.

The threaded end has very fine thread. Looks to be 1/4-36. I thought that I could extend the usable length of the rod with a threaded coupling; drill 1/4" hole near the end of a coupling; then insert a clevis pin for the carb throttle lever and throttle cable. But I can't find a 1/4-36 coupling. Searched most hardware suppliers.

I don't know if the rod was modified when the 3/4" thick car insulator was removed. The original bend at the top of the rod may have been cut off and a threaded rod welded on.

>> Is the threaded carb rod original?
>> Are all throttle carb rods for 235 3100's with carb insulator the same length? I will eventually buy one with the original bent end. (Anybody have one?)

Sorry for the long, drawn out post.

Thanks for your help,

I'm afraid what you have is something that a po has altered from stock form, probably when they removed the insulator. I noticed where the threads start that the threaded part is actually welded on, rather than threads cut on the rod itself. What you might consider, if you can't find an original, is fabricating your own rod from 1/4" round stock. It's not really hard to do, all you need is the stock, a good vice, maybe a hammer, and some patience. A welder would also be advised to add the throttle spring tab, plus a drill and a 1/16" bit for the cotter pin holes. It may take a few tries to get it right, but it can be done with those tools and a little time. That's how I made mine, only I used 1/4" stainless rod since that's what I had on hand.

Why not just cut the threaded part off just above the weld, and add a piece about 3/4" long to it? The threaded adapter is a good idea- - - -it allows a little adjustment of the gas pedal position for the most comfortable driving position.
Jerry

I have a '55 210(car) 235 with a cast iron powerglide with that exact threaded rod to the carb. Maybe as stated, it was switched from the original.

The 1957 Master Parts Catalog may have defined the source of the 1/4-36 threaded carburetor rod on my truck. I think that the rod is Chevy OE, but not correct for my truck.

The '57 MPC shows a 10-1/4" overall length 1/4-36 threaded rod for '55 V8's. Don't know if it would work on a 6-cyl.

The '57 MPC also shows a 15" developed length 1/4-36 threaded rod for '54-'57 6-cyl Hydramatic trucks. (longer than my carb rod)

The '54 MPC shows the length of #3696702 non-threaded '50-'54 carb rod for my truck to be 11-9/32" overall length

The '57 MPC shows the length of the '50-'57 carb rod to be 12-11/16" developed length. Different part number: #3717031.

I posted a request for a carb rod in "Truck Parts Wanted"

Thanks for all who gave input to my question.