High Speed stall!

[bluesnow6]

I have a 1999 Mercury 125 that I recently purchased. When giving 1/2 to full throttle, the motor runs fine for about 10 to 15 seconds and then stalls back to idle. I can get right back up again but stalls back every time. Have had a new high speed stater installed and rebuilt fuel pump, however the problem still exists. Any suggestions? Thanks!

 

[wilde1j]

Re: High Speed stall!

Check the fuel system for air leaks, bad primer bulb, clogged fuel pickup, etc. Does motor RPM pickup by pumping primer bulb or does bulb remain hard?

 

[Disturbed1]

Re: High Speed stall!

This is the exact same problem I am having with my motor. Yes, when the bulb is pumped the motor will pick back up and run like it should....for a few seconds and then back to idle speed. I replaced all the fuel lines (3/8" was existing, so that's what I put back on), tank selector valve, priming bulb and fuel filter. You can see the fuel in the in-line filter and it does not seem to be any air leaks. It seems more like a vacuum because the bulb collapses a bit. This is on an older Ranger boat, with a 1981 115hp Merc. Do you think the fuel lines are adequately sized? Fuel pump need rebuilt? I also removed and drained one of the tanks....it appears to be really clean inside and the fuel pickup tube is clean and nothing clogged in it.