1987 70 hp evinrude.

[Engraveart]

the motor starts fine and runs fine for about one quarter mile ,then boggs down. I have had the carbs rebuilt and the same thing still happens. I have been told to check the ignition coils ,does this make sense to you pros. thanks for any help tou might have

 

[flyingscott]

Do a compression test and check for spark when that happens. Use a timing light.

 

[racerone]

Not much to go on.-----How long have you owned it ?----Did this develop suddenly ?-----Tested it by running with another tank and hose ?----Tried operating the manual fuel pump ?-----Replaced water pump impeller ?----Tested oil injection ?----Mixing at 50:1 ?

 

[timguy]

It could be something as simple as an improperly vented tank. My guess is start with the fuel tank supply line or fuel pump.

 

[Evinrudemen]

I have heard the same, that coil may work fine just after starting, then when it is getting warm, it will stop working.