VCCA Home
Posted By: Youngfalcon Carb/Starting Issue? - 01/27/12 05:58 PM
My'34 runs perfectly once started but I am still having problems with starting it. Even after turning the engine over & allowing enough time for gas to be pumped in the the carb. no amount of pumping the accelerator or choking seems to be enough for it to start easily.

If I spray a liberal amount of gas or starting fluid down the throat it will fire right up. The carb was rebuilt by a VCCA member who specializes in rebuilds.

Any thoughts or suggestions would be appreciated!!!!!
Posted By: m006840 Re: Carb/Starting Issue? - 01/27/12 06:36 PM
Does it start right up if restarting immediately after running? Verify that the carb accelerator pump is working by looking into the carb with engine off and pumping the accelerator-you should be able to see the gas spraying in. Just a wag but perhaps the fuel pump is weak and even though you are allowing enough time to fill the carb, the flow is insufficient.
Posted By: Chev Nut Re: Carb/Starting Issue? - 01/27/12 07:38 PM
It may be fuel evaporation during the "hot soak" period.
First I would try opening the left side of the hood upon turning off the engine. This will allow some heat to escape.
When the tank is low add a quart of Kerosene to the gas. This slows the evaporation.
Is the heat riser free?

PS
Great story and pictures in the G&D

Posted By: Youngfalcon Re: Carb/Starting Issue? - 01/27/12 07:39 PM
Steve,

Thanks for posting. I do not see anything in the carb when pumping it with the engine off. As I said in the previous post, it looks dry. Plus I have noticed a hesitation when, while idling, when I press the gas. I did adjust the linkage on the accelerator pump, earlier, from the medium setting to the longer stroke and didn't see any difference. I don't notice the hesitation when driving but maybe I would if it was an automatic transmission. Any further thoughts?

Posted By: Youngfalcon Re: Carb/Starting Issue? - 01/27/12 09:03 PM
Chevegene,

You must have posted while I was, I didn't see your reply.

My main problem is starting the engine when cold. After its warmed up, I can get it started but still as quickly as it should. I think the accelerator pump may be the issue.

I just talked to the VCCA member who rebuilt it and he thinks so also. With a new tank, line, filter, and pump, we ruled out fuel.
Posted By: Mike33 Re: Carb/Starting Issue? - 01/27/12 10:12 PM
It could also be the 2 check valves in the carb that supply fuel to the accelerator pump.One of mine went bad and the pump would no squirt.
Posted By: Youngfalcon Re: Carb/Starting Issue? - 01/28/12 01:16 AM
Mike, thanks for your post also. I called the re-builder and he is sending me another carb. He asked several questions and thinks it most likely something to do with the accelerator pump. Hopefully the new carb. will solve the problem. If not....?
Posted By: Chipper Re: Carb/Starting Issue? - 01/28/12 01:28 AM
The lack of squirting problem could be one of several things. The small opening in the accelerator pump can easily get plugged. One or both check valves could be leaking or stuck. The leather on the pump plunger can be torn or worn.

The fact that the engine does not start when cold can be fuel flow, carburetor, ignition or compression/timing. The fact that it does start when starting fluid or gas is squirted down the throat would suggest a lean mixture which is harder to ignite than a rich one.

If you pull off the float bowl cover when it is cold is the bowl ~ 1/3 full? That is about the right amount. Is the float set to 3/8" from top of the float to bottom of cover? If you push down on the accelerator pump shaft by hand do you get noticeable resistance? Or does it go down easily?
© Vintage Chevrolet Club - Discussion Forum