05-03-2020, 04:23 PM
I still think it is a jet problem. Hand over the intake is equivalent to pulling out the choke and is often a trick used for getting a reluctant engine to start.
Normally fuel is fed into the engine via the main jet. However when the throttle is opened from tickover there is a delay in vacuum getting to the main jet and the engine will stall because the mixture goes weak.
The compensating jet holds a reserve of fuel in its gallery and is brought into play when the throttle opens, hence enriching the mixture. Once the revs have risen the main jet takes over.
Stalling on opening the throttle is classic compensating jet problem.
If it's ticking over OK try flapping the throttle open and shut and pull the choke at the same time. If it gets off tick-over it might well run OK.
Normally fuel is fed into the engine via the main jet. However when the throttle is opened from tickover there is a delay in vacuum getting to the main jet and the engine will stall because the mixture goes weak.
The compensating jet holds a reserve of fuel in its gallery and is brought into play when the throttle opens, hence enriching the mixture. Once the revs have risen the main jet takes over.
Stalling on opening the throttle is classic compensating jet problem.
If it's ticking over OK try flapping the throttle open and shut and pull the choke at the same time. If it gets off tick-over it might well run OK.
Jim