1989 Mercury 70hp WOT problem

[RyanBassBoat]

My 1989 70HP mercury started right up for me this year but its stalling out on me when I open up the throttle all the way. If I go at about half throttle it runs ok but once I open it up all the way it will go for about 15 seconds no problem, but then it bogs down and eventually stalls if I don't go back into idle. This was the first time I've taken it out this year, and it was running great all last season. I'm not sure whats going on but I was thinking it was a problem with the fuel line.

I did put a different brand of oil in there this year, but it was the same rated oil (TC-W3) so I don't think that?s my problem. Could that possibly make a difference?

Any insights would be appreciated, Thanks.

 

[RyanBassBoat]

Re: 1989 Mercury 70hp WOT problem

So its got to be a problem with the fuel line. As long as i pump the bulb every 20 seconds or so it runs wide open no problem...

so any tips for cleaning out the fuel line?

Thanks.

 

[verado7]

Re: 1989 Mercury 70hp WOT problem

you have either a bad fuel pump or bad primer bulb - if the bulb will pump firm and stay there with engine off - you have a bad fuel pump .