1974 Evinrude 40H.P.

[Machinist]

This motor starts up fairly easy and runs ok at half throttle. When I try to give it more gas it starts to sputter like it is going to stall. It will only run good past full throttle when it is not under a load. I would greatly appresciate any help!!! :confused:

[Kay9]

Clean the carb. Then check the diaphram (sp?) pump. That will likely fix your probs.

K9

[Machinist]

The carb has been cleaned and no difference in performance. The motor runs good at full throttle for 2-3 minutes before it acts up. Do you think it could be the fuel pump like you said before ? The motor runs okay with no load on it. This is my first boat so I have no clue what I am doing!

[FAST FRED]

Evinrude ignition coils have a VERY limited life.

New coils and ignition wire will cost little at NAPA, and will help resolve weather it is a fuel problem,

FF

[Machinist]

Thanks for the advise Fast Fred. I will replace the coils first, if nothing else at least they will be new.

[Kay9]

Yea coils first, then fuel pump. I had to do it all on my 64 OMC, now it runs great. If this dosnt do it you might hae the compression checked.

K9

[Machinist]

I have replaced the coils but have not had the chance to get it in the water yet. I also found out that the timingwith the high speed jet linkage needs a replacement for the adjustment screw.

[dd24skater]

I would check compresion