Motor Guru's help needed

[Gilbert Scales2]

I have a 90 hp Merc. It runs fine at high speed.... Idles in neutral great. However, when I idle in gear for a few minutes, it kills, and I have to pump the ball. I have no connections to the motor( everything is stiff) no quick connections. I checked for leaks on the gas line, none. I changed the fuel filter, and the water seperator filter. I am usually pretty good at this sort of thing, but I cannot figure it out. Any advise appreciated. Also the vent line is clear, no kinks in the gas line or vent line.

Bubby

 

[Jim B]

If i had to venture a guess id say its the fuel pump. The rubber in them wears out and when it does they dont work too well at idle. They dont cost too much to rebuild.



I had a similar symptom with my old motor and it ended up being the pump.

 

[Bayou Boy]

 

[Bayou Boy]

I have the same problem with my 50hp. I changed the bulb out thinking maybe a pinhole, still does it. I'm thinking it may be time for a tuneup. Mine is only a year old.

 

[TOMMY RICH]

It being a 94' and not a 2994 like in your profile:lol:

Very good possibiblity it may be the diaphram in the pump.

 

[Gilbert Scales2]

Wow Tee, I didn't know that was there. I corrected it, it's a 2004 Merc. I am going to the shop with it today. I have extended warranty until the end of November. I was hoping it was something simple, hate leaving it in the shop for a couple weeks.



Bubby

 

[TOMMY RICH]

Well that changes EVERYTHING:lol:

Seriously...that's pretty new to have a pump problem. Only prob I've had with mine was right after I got it, it needed a new coil pack. It was covered so I didn't mind.