C -1 '61 with dual carbs idling issues

[Mike B.]

New to vettes and still learning. '61 270 hp with 2x4's having trouble with idling. idle set at 900 rpms and after driving and warmed up you come to a stop sign and it is all I can do to keep it running until I get it stopped and can control the gas pedal. Then it will idle just fine until the next stop sign and it starts all over again. There is no black smoke pouring out exhaust. I checked for vacume leaks with stethascope and also used B-12 and cant find leaks. Checked posted threads in forums and did not find any related info. Any help would be great. Thanks, Mike 53700

[Terry D.]

Re: C -1 '61 with dual carbs idling issues

Sounds like maybe the floats are sticking. Have you checked the float level? When you say "it as all I can do to keep it running" does it want to stall out? If so how far do you have to rev it to keep it going?
Terry

[Mike B.]

Re: C -1 '61 with dual carbs idling issues

thanks for the tip. I was not thinking that way so you maybe on to something. It is not so much that I have to rev it up high it is more like I am trying to give it gas to keep it running. Which may answer my own question if it is running out of gas (i.e. floats sticking) then my playing with accelerator is just giving it gas until it reloads. It is a thought anyway. I will check the floats. thanks, Mike

[Mike B.]

Re: C -1 '61 with dual carbs idling issues

floats not sticking. Here is a little more description. after feathering the gas pedal and I get the idle to come back up before it dies it will idle ok the rest of the time it is stopped. until the next stop light and it starts over again. Hope this makes sense. Any help is greatly appreciated.

[Gordon W.]

Re: C -1 '61 with dual carbs idling issues

Float may be too high causing fuel to slosh on a stop which makes the motor stumble until you can get some air into it (to offset the fuel dump) by feathering the pedal.

[James G.]

Re: C -1 '61 with dual carbs idling issues

Float may be too high causing fuel to slosh on a stop which makes the motor stumble until you can get some air into it (to offset the fuel dump) by feathering the pedal.

My thought exactly Gordon. Now, what carb is flooding over? Suggest you buy the ST-12 SERVICE MANUAL for early Corvettes. Section 6-M is for fuel injection, AFB abd WCFB Carb adjustment and rebuild instructions. Floats are adjusted two ways. For WOT use, and idle. You may find the experience very rewarding if you tackle it yourself. Call a couple of Corvette mechanical buddies over and have fun on a Saturday morning.

[John H.]

Re: C -1 '61 with dual carbs idling issues

My thought exactly Gordon. Now, what carb is flooding over? Suggest you buy the ST-12 SERVICE MANUAL for early Corvettes. Section 6-M is for fuel injection, AFB abd WCFB Carb adjustment and rebuild instructions. Floats are adjusted two ways. For WOT use, and idle. You may find the experience very rewarding if you tackle it yourself. Call a couple of Corvette mechanical buddies over and have fun on a Saturday morning.

Jim -

He'll need the 1961 Passenger Car Shop Manual for that detailed 2x4 WCFB information - it isn't in the ST-12, as that setup was shared with the passenger cars.

[William C.]

Re: C -1 '61 with dual carbs idling issues

Are you sure the '61 has it? I know the '58 Pass car manual does, but not sure when the 2X4 was dropped from pass car, looks like '59 was the last year.

[Dennis C.]

Re: C -1 '61 with dual carbs idling issues

Are you sure the '61 has it? I know the '58 Pass car manual does, but not sure when the 2X4 was dropped from pass car, looks like '59 was the last year.

Bill,

My '61 Passenger car manual has the 2X4 WCFB info.

Dennis

[James G.]

Re: C -1 '61 with dual carbs idling issues

Are you sure the '61 has it? I know the '58 Pass car manual does, but not sure when the 2X4 was dropped from pass car, looks like '59 was the last year.

Jim -

He'll need the 1961 Passenger Car Shop Manual for that detailed 2x4 WCFB information - it isn't in the ST-12, as that setup was shared with the passenger cars.

Well, repairing ''ONE'' WCFB is listed in ST-12. No matter, Mike will get the idea

[Mike B.]

Re: C -1 '61 with dual carbs idling issues

Thanks again for all the info. I do have both manuals. Have been trying to locate the "professional" that rebuilt them prior to my purchase for a little inside info before completely going through. Here is a little more info as to what is going on but someone will have to tell me if it is related to issues at hand. First on the rear carb, (front carb does not kick in until late in the progression) the vent cap bowl makes a loud ticking sound all the time. Thought may be lifter but with steth it is the vent bowl, the front one does not make noise. Next, on the front carb the 2 hold down screws inside carb just behind the vent bowl are stripped and do not tighten. I discovered this while double checking all screws on both carbs for being tight and not causing any leaks. I placed a little locktight on threads and snugged at tight as they would go before spinning. By the way is there a fix for this problem?????

[James G.]

Re: C -1 '61 with dual carbs idling issues

Where do you live Mike? Gary Hodges is the resident NCRS Carb expert, but there are many others around the country. Gary is in Salem, Oregon. His website is http://www.garyhodgesramjet.com/index2.html

[Gordon W.]

Re: C -1 '61 with dual carbs idling issues

Nothing in a carburetor should or could create a ticking noise that I can think of. I've only ever rebuilt Holleys but the function is the same. That ticking noise must be coming from somewhere else.

The stripped screws are a real bummer. I'm not sure which screws you are talking about but again based on a Holley it sounds like squirter valve screws? I need to educate myself on Carters.

[Timothy B.]

Re: C -1 '61 with dual carbs idling issues

The stripped screws can be repaired with heli-coils very easily but you may want a carb expert to fix and also inspect the carburetor adjustments.

[Clem Z.]

Re: C -1 '61 with dual carbs idling issues

Thanks again for all the info. I do have both manuals. Have been trying to locate the "professional" that rebuilt them prior to my purchase for a little inside info before completely going through. Here is a little more info as to what is going on but someone will have to tell me if it is related to issues at hand. First on the rear carb, (front carb does not kick in until late in the progression) the vent cap bowl makes a loud ticking sound all the time. Thought may be lifter but with steth it is the vent bowl, the front one does not make noise. Next, on the front carb the 2 hold down screws inside carb just behind the vent bowl are stripped and do not tighten. I discovered this while double checking all screws on both carbs for being tight and not causing any leaks. I placed a little locktight on threads and snugged at tight as they would go before spinning. By the way is there a fix for this problem?????

the ticking could be the power piston moving up and down caused by vacuum pulsation and the stripped screws can be fixed by tapping the threaded holes deeper and use a longer screw.