Weber 34Ict smoking habit

What color is the smoke ?  Sooty black ?    White  ?   Real light blue ?   These are very basic questions but necessary.............Bruce

Need some clarifications:

Drumagination wrote:

I’m having a terrible time with my Weber 34 carbs (stock 1600 engine). After the engine warms up, the exhaust starts to smoke  like a chimney.( Color ?) The car runs fine, just extremely rich. ( As in black smoke? ) I think I am somehow flooding the crankcase with gas. ( Does the dip stick reading increase and smell like gas ? ) My fuel pressure is at 2.1 psi with brand new needle valves. (Try 1.5 lbs) I lifted the carbs with the electric fuel pump running and not a drop was leaked.  (Maybe the seats are leaking  allowing gas to bypass the seats when engine is off) Carbs rebuilt twice with new jets. ( Floats correctly set? ) My car has 300 miles on it and this issue is getting very old. Every time I change the oil, the exhaust is clean. Next day...bad again. Anybody else have this problem?

The smoke is a very light gray. Floats are set at 7mm with new needle valves. I can try 1.5 psi but 2.1-2.5 is recommended. I have changed the oil 4 times and I will note the dipstick level better going forward. Anybody out there like their Weber ict carbs?

With your set-up, my bet is on the 1.5 psi fuel pressure. Hope it all gets sorted out!

Black exhaust smoke would be running rich grey isn't, you mentioned "flooding the crankcase with gas"  . The oil will smell of gas and the dip stick reading will rise...I would start with a 1.5 pressure and see what happens.

Will do

thanks Alan

Alan and Musbjim

You guys nailed it. The fuel pressure gauge I borrowed was off by 1.5 psi. Now dialed in at 2 psi and not a hint of smoke. Thanks...

@Drumagination

EXCELLENT! Glad that worked out, plus the engine sounds great!

It's a great feeling troubleshooting your engine problems and putting in a fix that gets the the job done.

I love it when a plan comes together!

How do you measure the fuel pressure?

Well, the easiest way is to use a vacuum gauge with a "T" in the fuel line before the carbs.  Just about any auto parts store will have a suitable vacuum/fuel pressure gauge like this, from Harbor Freight:

https://www.harborfreight.com/...WJKmBNhoC-SUQAvD_BwE

You'll need a short length of 1/4" rubber gas line along with what's in the gauge kit.  Place the T in the fuel line just before the first carb, connect the fuel line to the other side of the T and attach the gauge to the trunk of the T.  don't forget to install hose clamps at all three places.

Start the engine, let it idle, wander back to the engine and check the pressure.  You can test it at idle and up to, say, 3000 rpm.

Good hunting!

Thank you Gordon, but how do you adjust the pressure?

Either with a self-regulating electric fuel pump, an adjustable pressure regulator(with an electric pump) OR extra gaskets under a mechanical fuel pump. I had to add 6(total 7) gaskets to a customer's sand rail that I put dual Solex 35PDSIT carbs on. This dropped it to 1.5 pounds, it was OVER 3 pounds, which overwhelmed the Solex float valves.

Aircooled.net sells mechanical fuel pump gaskets in packs of 10 expressly for this purpose.

Thank you

Paul ISAAC