Sticking Throttle, Fuel Injection

[Larry M.]

On my 64 FI car, took it for a test drive today after replacing radiator, water pump and fuel pump. I opened it up (90 mph) and, when I let off the gas, it kept going at over 6500 rpm. Had to cut the ignition with a huge backfire and rolled to a stop. Under the hood jiggled the bell crank and it released. Had the same issue a while later and cut the switch immediately. This time I tried to jiggle the acclerator rod inside....no result. Again, under the good, moving the bell crank released the throttle (when the return spring would not). I've done no analysis yet but think a little knowledge if better than hunting and pecking.

I'm wondering about the throttle plate/shaft in the air meter. This seems like a pure mechanical issue as the bell crank was definitely stuck in an open position. What would you look for?

[Michael G.]

Re: Sticking Throttle, Fuel Injection

A soft place to crash?

[Stuart F.]

Re: Sticking Throttle, Fuel Injection

The back firing is a scary thing. Back in the day, I had a 58 Fuelie engine in my 56 Chevy. I had sometime before sold the Fuelie unit in exchange for dual quads plus cash, then went to a home built Rochester 4 barrel. I also had an old tri-power from late 56 which used old Holley 2 barrels that were very similar to Stromberg 97's along with an el-cheapo progressive linkage. One night I went out for a clean out run through the gears. After winding out second, I clutched to go to third and my linkage went past zero to hang up wide open. My sun tach near buried as I quickly shut off the ignition switch. The engine backfired many times and I would have sworn I blew up the engine. I stopped and checked under the hood, doing a brief fix of the linkage, then went to try a start up. The engine started right up and ran like never before. I figure I stretched the rods a bit or something, cause it ran like a champ, but I learned a lesson and went back to my home built 4 Barrel for good. I had over heated that engine twice when I had it in my 50 Chevy coupe, and each time it seemed to run better. I sold the car to young fellow who wanted the dual fours put back on. He raced it every night, and finally wore it out. My buddy installed anew 327 in it for him and told me he tore down the 283, noting that every piece of that engine was completely worn out, but it NEVER blew up even though the kid actually tried to do just that.

Stu Fox

[Larry M.]

Re: Sticking Throttle, Fuel Injection

I looked this morning and with my wife operation the gas pedal I looked under the hood....simple issue...the throttle rod trunion was hanging on the spark plug wire support....but I also found another issue which I want to ask about. I found that the plastic sleeve and rubber busing were installed backward so the cotter pin was against the rubber peice and had chewed it up, contributing to the problem. Luckily I had one which I'd bought years ago from corvettefasteners.com part number UH-4. When I got it out the head or flange on the bushing was large enough to cover the entire rubber bushing so the cotter pin cannot get into it. What I took off and what I see on supplier sites is a bushing with a smaller head or flange. How large should the flange on the plastic bushing be?

[Dan H.]

Re: Sticking Throttle, Fuel Injection

Larry, the small bushing is like the originals, large one is later replacement one.

[Larry M.]

Re: Sticking Throttle, Fuel Injection

Thank you....I'll get one coming.