75 HP Merc problem?

[Barnacle_Bill]

I have a new to me 1995 Merc 75HP. While out running WOT the motor suddenly acted like I was slowly throttling back and died. Primer bulb checked good. The motor started right back up and idled good but would die when I tried to give it gas. It did this several times and then started to act better. I took it back up to WOT and it acted like it was going to die again so I throttled back a little and it ran ok the rest of the way in.

Inspection didn't show much. No loose connections. All fuel hoses and bulb good. No loose linkage. I did find the arm from the trigger loose to the point it rattles but appears to be working fine. I found an inline filter and replaced it but don't think it was causing a problem. Since I don't know the history of the motor I'm going to rebuild the fuel pump. Am I forgetting anything?

 

[tashasdaddy]

Re: 75 HP Merc problem?

cleaning rebuilding the carbs, sound like high speed jets are clogging. and replacing the impeller, if you don't know when last done.

 

[Barnacle_Bill]

Re: 75 HP Merc problem?

Already got an impeller on order. My main concern right now is that loose trigger arm. My 150 was loose but didn't rattle. Is that just the nature of this particular beast? When I say loose, I mean up and down, not back and forth.

 

[Barnacle_Bill]

Re: 75 HP Merc problem?

FWI Merc changed the check valves in the pump from rubber to plastic. I wonder why?

 

[j_martin]

Re: 75 HP Merc problem?

The rubber ones fold up like a potato chip in the alcohol fuel. BTDT

 

[Barnacle_Bill]

Re: 75 HP Merc problem?

The rubber ones fold up like a potato chip in the alcohol fuel. BTDT

Thanks for the info. Maybe I fixed my problem.

 

[jmburock]

Re: 75 HP Merc problem?

The stator should be keeping the trigger arm from having vertical rotation, should only be about 1/2" of horizontal rotation. Is part of the plastic of the trigger broken or something? Are all the trigger leads testing o.k? Check the linkage on the trigger to make sure the ball is in place and not broken out of the little plastic snap basket.