78 140 hp fuel pump ?

Motors not running just right seems to run alittle lean I'm thinking maybe fuel pump. Sould my bubble on the fuel line stay tight after priming it and I would like to know if there is a way to test the fuel pump. Thanks

We'll need a better description of just how that engine's running.... specifically.

The "Fuel Primer Bulb" does not stay hard when the engine's running. The primer bulb is normally laying somewhere on the deck in a horizontal position and as such... the fuel drops down to the halfway point which is normal.

Do this.... Have someone constantly pump that fuel primer bulb (acting as a manual fuel pump), if that cures the problem, either the pump has failed, a fuel/air leak exists somewhere between the pump and the fuel supply, or the power pulse from the cylinder that operates the fuel pump doesn't exist.

The motor is sneezing but seems to stop for awhile and run fine when I pump the bubble. Then when it starts sneezing again the bubble seems to have no pressure. When fuel line is not hooked to motor bubble will stay hard. This motor is new to me iv never run it. Just soaked and cleaned carbs but I think the carbs are right. The gas is new.

Compression is 110 to 120. And I have good spark

The pointed end of the fuel pump is facing up i dont know if this this right or wrong or if it even matters but on a previous motor I had the pointed end faced down

Sneezing...... The engine is running lean!

Have the carburetor face plate removed so you can get at the carburetor throats.

Have the engine running with the engine sneezing. One throat at a time, place two fingers into the carburetor throat (acting as a manual choke). When the engine smooths out, you've found the offending carburetor and the side of the carburetor that contains the slow speed jet for that cylinder.
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On the side of that carburetor, near the rear flange that is bolted to the intake manifold, you'll see a small aluminum screw. In back of that screw is the slow speed jet.... clean it carefully with a piece of single strand steel wire.

If you had removed that jet when you cleaned the carburetors... what number is inscribed on the side of that jet? It should be #33, meaning the inside diameter is .033 .
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If when cleaning those carburetors, you DID NOT clean the four high speed jets that are located laying horizontally in the bottom center portion of the float chambers... way in back of the drain screws/bolts, carefully do so with a piece of single strand steel wire as solvent just doesn't do that job properly, and fuel must flow freely through those high speed jets before fuel can gain access to any other fuel passageway.


Let me know if this cures your problem.