Thread subject: Whaler Central - Boston Whaler Boat Information and Photos :: 1981 25 Evinrude

Posted by jdwaquoit on 07/30/08 - 5:01 AM
#1

Changed sparks, cleaned carb, new gas tank, Startron added, new line and bulb, all linkage in good shape - BUT - it will idle for 25 min and quit. Under high speed it will quit after 5 minutes. Any Ideas. Im all out and no marine mech in my area will touch a 25+ year old engine
JD Waquoit Falmouth Cape Cod

Posted by Joe Kriz on 07/30/08 - 9:18 AM
#2

Sounds like you might be overheating.
I had a 15 hp that was doing the same thing as the water pump was not working.
Have you replaced the water pump impeller?

Do you have a telltale stream of water coming out the top of the engine cowling?
How about the thermostat? Is it stuck closed?

Posted by David Wolfe on 07/30/08 - 10:22 AM
#3

Sounds like it could be the coils breaking down after they get hot. If ti was a water pump problem it should go into slow idle and not speed up. Just a though

Posted by jdwaquoit on 07/30/08 - 12:30 PM
#4

I do have the tell tale stream, but know that you mention "overheat" after a considerable length of Idle time, if I felt the engine by hand it was cold! so I figured that the cold water feed was causing the engine not to warm up... is that another symtom of overheating? Thanks for all the replies

Posted by msimon on 07/31/08 - 8:13 AM
#5

Once warmed up, you should be able to hold your thumb on the cylinder head. It will be warm but not so hot that you can't hold your thumb on it. If it is hot, I agree, check the water pump and thermostat. If your running in salt water at the Cape they can get plugged even though you flush after use. Coils "breaking down" due to heat would be extremely rare. It sounds like its starving for fuel. Did you rebuild the carb or just spray some cleaner in it? Carb cleaner will not clean a plugged high speed jet or bad needle seat. Also check the screen at the fuel pump. Let me know. The carb is one of the simplest OMC ever made and is very easy to rebuild.

Edited by msimon on 07/31/08 - 8:17 AM

Posted by Derwd24 on 07/31/08 - 8:33 AM
#6

As it's quitting, how's the primer bulb? Have you tried re-priming as it's running down? Wondering about the fuel pump...