Gas Leaking from exhaust while priming bulb.. ?

[frankygandolfo]

Gas Leaking from exhaust while primeing bulb.. where to start?

 

[Nordin]

The fuel pump diaphragm is bad, ruptured or hole in it.

 

[frankygandolfo]

The fuel pump diaphragm is bad, ruptured or hole in it.

Ok, i will check that out today. Can it be the carb needle valve. i think i read that somewhere.

 

[Nordin]

No, the fuel pump is driven by the underpressure/overpressure from one cylinder in the crank case.
If the diaphragm is ruptured you will pump fuel through it in to the crank case when you prime.
If the carb needle valve is leaking you will see fuel coming out the vent hole in the carb.

 

[frankygandolfo]

No, the fuel pump is driven by the underpressure/overpressure from one cylinder in the crank case.
If the diaphragm is ruptured you will pump fuel through it in to the crank case when you prime.
If the carb needle valve is leaking you will see fuel coming out the vent hole in the carb.

gotcha, thanks man !

 

[jerryjerry05]

It helps if you tell the year and model of the motor.
They used 2 types of enrichment on the Force/ Chrysler

 

[jimmbo]

There was no mention of the engine being cranked while the Primer Bulb was being squeezed. so...
For Fuel to make it from the Carb, to the Exhaust, when the Primer Bulb is being squeezed, it would have to go through the Intake Manifold, through the Reeds, into the Crankcase, fill up the Crankcase enough to spill into the Cylinder via the Transfer Ports, and then exit the Cylinder via the Exhaust Ports, once there is enough Fuel in the Cylinder. If the the Fuel Pump Diaphragm was passing Fuel the steps after the Reeds all apply. That much Fuel would Hydro-lock the engine in any attempt to start it.

 

[frankygandolfo]

It helps if you tell the year and model of the motor.
They used 2 types of enrichment on the Force/ Chrysler

89 force 85 hp, 856F9F

 

[frankygandolfo]

No, the fuel pump is driven by the underpressure/overpressure from one cylinder in the crank case.
If the diaphragm is ruptured you will pump fuel through it in to the crank case when you prime.
If the carb needle valve is leaking you will see fuel coming out the vent hole in the carb.

Hey man thanks for the tip, i went home opened up the fuel pump and the diaphram had 2 large holes. I have the new one coming in soon.

It seems like the pump builds its pressure from that middle cylinder, but have you heard of someone hooking one of these up to replace the origianl pump with some type of adaptor plate?

 

[jerryjerry05]

If you can hook it up?? Then it should work.
They all use the same system just the mount is different.