Cleaning the Idle Circuit in a Solex Carburetor

Does your car stall every time you come to a stop? Can you not keep it running without giving it gas? One possible cause of this problem is a clogged idle jet or idle passage in your carb(s), particularly if this came on all of a sudden. This is the only thing in the Solex carburetor that would cause this. There may be other issues external to the carb that might cause this, but I won't get into that here. Since cleaning the idle jet and idle passages is so easy, I would suggest you start here and rule out your idle circuit as the problem.

This is the procedure for cleaning out the idle jet and its related passages.

• The idle jet is located up high on the carb and sort of points toward the "J" shaped injection tube.

• Start by removing the four screws holding the top of the carb on. 

• With the top of the carb removed, you should be looking at the carb gasket. Carefully remove it.

• With the gasket removed, you can now remove the idle jet and the screw plug, which gives you good access to the idle passage. The idle jet is the only jet on the carb that has both a hex head for a wrench and a slot for a screwdriver. The screw/plug may be difficult to remove. Use a good screwdriver that fits the slot well. Should you be unable to remove the screw/plug, you likely can still clean the idle passage, but you have much nicer access with it removed.

• With the idle jet and screw/plug removed, you can now take your carb cleaner spray and clean both the jet and screw/plug as well as shooting a strong spray into the idle passage by way of the screw/plug hole. Then use an air compressor to dry things off. A strong shot of air into the screw/plug hole should blow out any carb cleaner residue into the carb throat and prove to you that the passage is clear. Do not try to stick any metallic objects into any of the jets on the carb to try to clean them as that could damage them.

• Reassembly is the reverse of disassembly. Unless you have a handful of new gaskets available, you can likely reuse the old gasket. If the old gasket was damaged during disassembly, then replace it. If the old gasket doesn't seal properly after reassembly, it is not a big job to replace it after the fact.
• It is probably a good time to check your carb synchronization if you have dual carburetors and also a good time to make sure your idle and mixture is correct. This is covered in the service manual.

Enjoy your renewed, nice, smooth idle!