C1- Dual Carburetor Smoke Problem

[Jimmy Johnson]

I have a 59 245 HP that smokes slightly when idling. When I kick down the fast idle it puffs a dark black smoke. The timing is correct. I have AC 46 plugs. The plugs and contacts are set to specification. The idle is smooth and has been set using a vacuum gauge. I know the fuel is rich because the plugs will eventually foul, but if I lean it out the engine back fires and I get low vacuum readings. Can you help with this problem.

Thanks, Jimmy

[James F.]

Re: C1- Dual Carburetor Smoke Problem

Jimmy,
Your beast sounds like it's acting pretty normal. You didn't mention the vacuum gauge readings, would be nice it they are higher than 17" vacuum, 19" would be better yet. If vacuum is reasonable, suggest you experiment with alternate metering rods. WCFB's were intended (for a reason) to easily change rods. Contact Chuck Smith and see what rods he recommends to lean out the idle ciruit. I purchased four #1366 rods which leaned out the idle circuit on my '56 2 X 4 system. These should work for your system as well. Beyond that, using your present rods you can experiment with AFB jets. One does this by calculating the area of the hole in the original jet, minus the area of the idle section of the rod and then picking out a jet maybe .003 smaller (for starters) in size. Processes like this was the main reason failed math! Hope some of this helps. Regards,

[James F.]

Re: C1- Dual Carburetor Smoke Problem

Jimmy,
Your beast sounds like it's acting pretty normal. You didn't mention the vacuum gauge readings, would be nice it they are higher than 17" vacuum, 19" would be better yet. If vacuum is reasonable, suggest you experiment with alternate metering rods. WCFB's were intended (for a reason) to easily change rods. Contact Chuck Smith and see what rods he recommends to lean out the idle ciruit. I purchased four #1366 rods which leaned out the idle circuit on my '56 2 X 4 system. These should work for your system as well. Beyond that, using your present rods you can experiment with AFB jets. One does this by calculating the area of the hole in the original jet, minus the area of the idle section of the rod and then picking out a jet maybe .003 smaller (for starters) in size. Processes like this was the main reason failed math! Hope some of this helps. Regards,