Kadron Carbs bad idle, icing on passenger Side

[Florian[Flo]]

Hello everyone
I'm from Germany and drive a 1302 with a KADRON twin carburetor system.
I'm having a few problems with the carburetors. Unfortunately, there are very few people in Germany who are familiar with these carburetors and know anything about them, so I hope you can help me.

I bought the carburetors in the summer and completely overhauled them myself. The parts came from Kaddieshack. All the gaskets were replaced, the float needle valve is new, and the throttle valves have Jeff's bearings.
I also bought 32 mm venturis with the right jets for my engine. (See below for engine details.)
I also installed the COBRA fuel pressure regulator and adjusted it correctly.
I opened the vacuum port on both carburetors and connected it to my 123 distributor via a T-connector.

The engine ran very well (in August) at first. It was drivable.
Unfortunately, I had a false air problem at the carburetor base, which is why I had to remove the system again to plane the sealing surfaces.
At the same time, I installed original Kadron intake manifolds instead of the EMPI ones. (October). I again used all new Gaskets.

Now, months later, I wanted to test whether everything was working. I tried to adjust the linkage (CSP linkage) as best as possible according to Jeff's instructions.
The engine runs with 7.5° before TDC ignition. I have a 7,5mm Balance Tube installed.

Unfortunately, I can no longer set a clean idle speed. The engine gives me the impression that it is only running on one side or that one or more cylinders are missing. After running for a short time, ice forms on the carburetor and intake manifold on the passenger side. The intake manifold is also cold. The cylinder head is slightly warm.

I have checked the ignition cables; they are all seated correctly and have good contact. I have now ordered a new distributor finger and a new distributor cap to rule out any other possibilities. But as i wrote, in August everything worked the way it should..

FJs Book is already on its way to me.

Do you have any other ideas about what my problem could be?



My engine (driven approx. 500 km):
-> 1776 cc
-> CB2280
-> 8.25:1 compression
-> KADRON dual carburetors
-> 123 distributor with vacuum connection
-> 043 AA cylinder heads
-> Ahnendorp Streesport exhaust

I would be very grateful if someone could help me.

Best Regards from Germany.
Florian

[Bruce2]

One by one, disconnect each plug lead. You will find that the engine is only idling on 2 cylinders. This is because all of the manufacturers do not know how to design a proper intake manifold. Each Kadron carb is on a plenum type intake. A plenum requires a large volume under the carb for the individual cylinders to draw from. But the intake manifolds do not have this necessary volume.
You can fix the intake manifolds by cutting out the wall between the two runners. Take as much as possible out, leaving a short section of the wall at the bottom to press down on the gasket. Once you do this, the engine will idle on all 4 cylinders.