1990 HP, skips/misses after running out of gas...

[fpdiver]

didn't really run out of gas...every once in a while the ball collapses (inboard tank) and caused the motor to die. (a few bulb pumps, open the gas fill to let the vacuum up and all is well)


But, this time, after stalling out at 40% power the motor started skipping after restarting. Also skips on a new gas, external tank so it isn't the gas or the tank. It starts great and runs great, except for the skip/miss that at idle causes it to stall.


My plan is to change the plugs (fouled due to running lean) and to silicone spray the wires because when I touched one it gave me a nasty shock. (moving the wires around, away from the block and each other, (while not running) had no effect).

Any other ideas?

Possible coincidence?

thanks for your help.

 

[Frank Acampora]

Re: 1990 HP, skips/misses after running out of gas...

Well first, take care of the tank problem. It is imperative to ensure a constant supply of fuel to the engine. Find out why the primer bulb is collapsing and correct it. This is not a condition to treat lightly or accept. You are playing with fire.

On a multi carb engine, if the fuel bulb collapses and all carbs run out of fuel, the engine loses power and slows or stalls. However: Since some carbs are above others, it is possible that only one carb would run out of fuel or would run out faster than the other(s). The other carb(s) and cylinders continue to carry the engine while one cylinder runs lean. It goes into detonation and melts the piston.

As far as the miss at idle, you have a smoking gun with the wire, however, do not discount plugs and incorrect carb settings. Fouled plugs and/or too lean a setting usually causes spitting and stalling at idle.

 

[fpdiver]

Re: 1990 HP, skips/misses after running out of gas...

....the fix for the inboard tank, for now, is to use a carry on. This winter we will go back to 1 filter (presently 2) and change the fuel lines and vent hose.


I think with a melted piston the running would be much uglier than a miss every 2-10 seconds.


Hopefully we just fouled a plug bad with the lean mixture....would prefer not to change the wires since I think that means changing the magic blue boxes.



Frank