The Cal-look Lounge

Hi, Problem with cylinder 4. It's a carburetor problem- it fells like the idle jet is plugged, but it is not.....How can I go about thoroughly cleaning the idle circuit? Prefer not to remove the carb from the car. It is the carb for sure...... , if i screw the idle jet a little bit out cylinder 4 starts running...... ??? ??? ??? ???

Only proper way is to remove lead plugs from the cross-drilled paths and clean them physically - I can't imagine how it could be made while the carb's in the car.

You may also try to adjust the bypass screw but it probably doesn't help.

I've heard good things about ultrasonic cleaning, however I've also heard that it may loosen the lead plugs. I'm tending to the direction that ultrasonic cleaning is ok for carbs.

I remowed the idle mixture screw and the idle jet. Thinking about carburetor cleaner and air pressure and some physically cleaning with a bicycle brake cable :-( No time to remove the carb  :'( :-\ :-\

If you push wires and cables into those delicate passages you won't have to worry about spending any more time on that carburetor: you will probably destroy it. Never use scribes, awls, wires, or any other hard object in those passages. Pressure is a little bit questionable as it can lodge things in there even more tightly and even blow out the plugs at very high pressure.

Disassembly and chemical and/or ultrasonic are usually the best options but you can also try an old trick.

Fatten up that idle circuit quite a bit with the mixture screw. Remove the air filter from the offending carburetor and crack the idle jet loose just a tiny bit. Start the engine and operate the throttle from the back of the car. Spin the engine to about 3,500rpm and hold your hand over the velocity stack on the offending cylinder. That will exert a ton of negative pressure on the idle system and the atmospheric pressure on the fuel in the float bowl will push a ton of fuel and hopefully the obstruction through the system and out the idle-fuel port.

Or it won't in which case you'll have to just pull the carburetor and do it the right way.

Thx!!! That|s a really nice Idea!!!  ;D ;D ;D Hope it works......

Thx hotrodsurplus, it works!!!  ;D ;D ;D

Awesome! It's worked almost every time I've done it. If we could get paper elements that fit our filter housings we wouldn't have to worry about clogged idle jets anymore. Clogged idle jets are proof that those cotton-gauze elements like K&N let big dirt through.