Adjusting new valves

Anonymous-0

Well-known Member
Hello once again Allis friends. I am still working on my Allis B. I believe I have it properly timed now. It starts extremely quick and runs ok. However it appears to be running rich. I have recently done a valve job and put on a rebuilt carb. My question is this. Could the adjustments on the valves be wrong causing it to run rich and covering the plugs with carbon? What is the best way to properly set adjust these new valves? It runs very good at a low idle and as you increase the idle it begins to run slightly rough and blackish smoke out of the exhaust. As it gets warmer it seems to run a little rougher also. I have played with the two adjustments on the carb but they don't seem to help. I can make it worse but not any better.
Thanks in advance for all your help.
 
The book calls for .010 on both exhaust and intake valves. I always set them to .012.

The top screw on you carb in idle only. You work with that adjustment with the stop screw on the throttle plate arm to get the slowest idle. Above idle that screw has nothing to do in how it runs. After the idle is set you then set the engine to high idle or wide open. You then adjust the power jet adjusting screw to the highest RPM and turn the screw back in until the engine starts to slow. If it still runs black smoke, turn it in a little more. Most B's do not have an adjusting screw for the power jet.
 
My B had the same problem...I rebuilt the carb and had the carb body soaked in acid...apparently there are some air portals in the carb that are not real visible, and can become clogged...if that happens, she'll run rich and struggle. Valve adjustment would have to be waaay off before it would cause a rich/lean problem.
 
I think your carburetor is set too rich. If you have a main jet adjusting screw near the bottom of the carburetor you need close it by turning it CW. This will lean the fuel mixture. The blackish smoke is a sign that the mixture is too rich. Hal
 
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