Low RPMs

[LCG]

I bought myself a hobby car last year and it went from hobby to obsession. Anyway, I did not take my boat out at all last year. This year I found my electric fuel pump motor had failed. I replaced it and the two diaphram pumps and got it running again.

It's starts right up, runs smoothly. However, when I went WOT it would only reach 4500 rpms, where I usually got 5500. I had treated the tank with Stabil last year and added a some gas to freshen it up. Could it be the gas is just old or something else?

[jb123]

what model and year motor do you have?

[LCG]

It's a 2001 150 SSII EFI

[jb123]

try using an auxillary tank and ball right up to the motor filter, see if that helps at all to rule out tank side issues.

you replaced the HP pump ???

then have the o2 sensor checked/ cleaned.

http://www.boatsetup.com/O2sensor.pdf

[LCG]

I'll try the aux tank and check the O2 sensor article. Yes, I replaced the HP pump.

[jb123]

ouch. was the filter inside cleaned also?

[LCG]

The screen on the bottom of the pump was gunked up, which is what I believe caused the pump to burn up. I cleaned and it seems to pump fine now. Took it out for several hours. I notice it was a bit sluggish, then realized there was a problem at WOT.