when a dozer is idling its rpm are at 90,000 to 95,000
Could be dirt in the carb's idle circuit. Maybe a vacuum leak.
the rpms should rise and then drop no more then 500 rpms when the fan on the radiator turns on and then off.
Mine is between 500 and 600 rpm's after the engine is warmed up.
IAC (Idel Air Control Valve)
There is a black screw behind the carburetor, if you turn it clockwise while it is idling you will hear the rpm's drop.
It could be the camshaft position actuator or a few other things.
My 2007 Volvo uses .5-.6 gph at idle (600 rpm), if I set it for a hi idle (900 rpm) it uses 1-1.1 gph.
mass air flow sensor
The oil thins when hot and the oil pump is driven off the engine so, the lower the engine rpm's, the slower the pump turns.
800 RPM
Timing is 4 degrees before top dead center with the distributor hose disconnected and plugged. The warm idle speed is 500 RPM.
The idle should be at 8 to 900 rpms, if lower then theres a idle screw on the side of the throttle body in front of the injector, turn it to where the idle needs to be.
Yes - You have a vacuum leak