New 50 hp 2 stroke with fuel problems

[Blindduck]

I have a 2009 50 hp 2 stroke elpto that keeps running out of fuel at trolling speeds. It will keep running if you pump the primer bulb which is empty when stalling. Seems to get worse as the engine warms up. The motor starts fine and runs great at high speeds. Can't seem to put my finger on this one.
I have replaced the tank which had a cracked pick up tube. Really thought that would be it. Since that I have rebuilt the fuel pump,new fuel filter, replaced the fuel lines and primer bulb. Still same thing. I also pulled the carbs off today and checked the bowls and seats which were all clean. This engine is well taken care of and is on the water at least every other weekend while either duck hunting or fishing. Neglect is not the case. Dealer can't find anything wrong but why does this keep happening? If anyone can help I would appreciate it. Thanks.

 

[Blindduck]

Re: New 50 hp 2 stroke with fuel problems

Still needing some help here. Anyone. Could timing or bad spark plugs cause poor fuel pickup since the fuel pump works off the engine?

 

[Silvertip]

Re: New 50 hp 2 stroke with fuel problems

The fuel pump works off pressure/vacuum pulses from the crankcase and is not affected by ignition timing. It is apparently a bad fuel pump and as such, the pulses are not strong enough at slow speed to pump sufficient fuel.. It works at high speed because the pulses are strong enough -- at least at this point. But because it currently runs fine at high speed doesn't mean it will continue to do so. Replace or rebuild the pump.

 

[Blindduck]

Re: New 50 hp 2 stroke with fuel problems

Thanks for your help silvertip. I pulled off the fuel pump and noticed that when I rebuilt the pump I did not get the gasket sealing the pump housing to the block right over the hole. Pretty shure that was it. Corrected the problem and it does not seem to stall at least running on the ears. I will need to give it a lake test to make shure. Wouldn't you think they would catch that at the shop????
Thanks again.

 

[CharlieB]

Re: New 50 hp 2 stroke with fuel problems

An O-ring failure on the fuel hose quick-connect fitting may allow air to be sucked in as the fuel pump pulls a vacuum on the hose yet seal when you pump the primer bulb.

Test by temporarily using a clear hose between the fuel pump and carb(s). Run the motor and watch for any air bubbles passing thru the clear hose, indicating air sucking into the system.

Be SURE to remove the clear hose once finished with repairs as it is NOT approved, nor recommended for fuel use, only for testing and proving a problem.

 

[Blindduck]

Re: New 50 hp 2 stroke with fuel problems

To eliminate the fittings, I ran the fuel hose from the tee on the oil injection line directly to a barbed fitting I installed on the tank. No fitting and still ran out of fuel. I will try that if I am still having problems. Thank you.