1990 Evinrude 25 HP 2-Stroke Problem

[cgilcher]

The engine runs fine at idle and at full speed until the engine warms up and gets hot. The engine will suddenly die on me at full speed. I immediately restart the engine and will run fine for a few minutes and do the same thing. I have had it to several boat shops in which the have changed the spark plugs and fuel line coming from the tank but this hasn't helped. Anyone have any ideas? I was thinking it could possibly be a coil but wanted to check before I go out and buy anything.


THANKS!!!!!!!

[cr2k]

Fuel tank vent open? Could also be fuel pump.

[Daviet]

You say the engine gets hot, is it overheating? You could check spark when it happens and see if you loose spark. Have you checked the high speed jet to see if it is clogged?

[cgilcher]

to the best of my knowledge, it is not over heating. What clues would tell me if this is happening. The water pump seems to be pumping correctly and the stream of water out of the back of the engine is warm but not hot. If it was a jetting issue, wouldnt it be a problem all of the time and not an intermittent problem? Sorry for all of the questions but I am not real familiar with small boat engines. I actually work with rather large natural gas engines daily so 2-stroke stuff is kind of greek.

[cgilcher]

I do not see any vent on my fuel tank. Could you please tell me where I might find it. The fuel line holds a prime with the bulb.

[scotteam]

fuel vent as others have said. The new tanks are opposite of the older style tanks. on the old tanks you leave the vent closed. on the new plastic type tanks you open the vent. Why it is different i have no idea but they are

[Daviet]

On the jetting question, you have two different circuts in the carb, high and low speed. If you have a plugged high speed jet it will not allow enough fuel to maintain high RPM. It is possiable for the high speed jet to be plugged and the engine will still idle perfectly.
If your tank is not venting properly it would try to suck the primer bulb flat, is that happening?
In the link below the low speed orifice is #1 and high speed is # 22.
http://www.ishopmarine.com/ishop/jsp...ier-100-005-EJ

[larryg]

get a inline spark tester from advanced auto.check the spark on the coils.set it at 7/16. also ,when started pull top n bottom plug one at a time.if they go to quit everything is ok.doesnt sound like an ignition problem since it restarts.i had same problem with my 20,had a bad coil,broken reed and carb was getting fuel line in it,from the ethanol in the fuel.check the spark and let us know,

[Monte1961]

The engine runs fine at idle and at full speed until the engine warms up and gets hot. The engine will suddenly die on me at full speed. I immediately restart the engine and will run fine for a few minutes and do the same thing. I have had it to several boat shops in which the have changed the spark plugs and fuel line coming from the tank but this hasn't helped. Anyone have any ideas? I was thinking it could possibly be a coil but wanted to check before I go out and buy anything.


THANKS!!!!!!!

Well the fact that it starts right back up tells me it's a fuel problem. As a rule, if it was a bad coil then it would have to sit and cool in till coil reactivated in most cases, or at-least in my experience. Would check fuel pump pressure and if good, carb/s float/s. Good luck and post back to let us know how you made out!