40 HP Evinrude Big Twin

[mdiprisc]

I would like to find out what year my motor is? Mod. # 40952R, ser. E01379. I also have a problem with it not running strong at high speed. It surges when I open the throttle full. I live at 6500 feet? It idles great. Thanks.

 

[trumpetbucks]

Re: 40 HP Evinrude Big Twin

That motor is a 1969. Have you checked your high speed mixture and/or jets?

 

[Paul Moir]

Re: 40 HP Evinrude Big Twin

The engine seems to vary a little bit, then your probably looking at either a weak fuel pump, or a carburation problem. If it's the pump, pumping the primer bulb while running should relive the symptoms. If it doesn't help at all, probably rebuilding the carb will fix it. I'm pretty sure there's no high speed mixture adjustment on your engine.<br />If the engine suddenly gives you a kick in the pants, like it's picking up half it's power, then your looking at a coil that's arcing over. Pull the flywheel and inspect them for cracks. If they're original, they're probably shot.<br />Good luck!

 

[billy runyon]

Re: 40 HP Evinrude Big Twin

have a 40hp evenrude big twin and need to know the rotation of water pump empeller. Some one had it apart before I got it and I believe that the empeller had been put in wrong.

 

[jasper60103]

Re: 40 HP Evinrude Big Twin

have a 40hp evenrude big twin and need to know the rotation of water pump empeller. Some one had it apart before I got it and I believe that the empeller had been put in wrong.

You should have started a new thread, but the drive shaft turns clockwise so the impeller fins should point counter-clockwise.