1975 70hp evinrude

troller59

Recruit
Joined
Jan 26, 2019
Messages
4
yea so motor will run terrible for about 15 minutes. barely moves the boat. then just takes off and runs great all day. wondering if anyone else has had this problem ?
 

flyingscott

Fleet Admiral
Joined
Apr 8, 2014
Messages
7,985
Check for spark when that is happening. Are you letting the motor warm up? Are yyou using the primer bulb on the fuel line.
 

troller59

Recruit
Joined
Jan 26, 2019
Messages
4
i use the primer bulb before starting. used to run good right away. last few yrs its doing what i described. i thought maybe bad plug wires but they are a coil and wire unit. about 80 bucks apiece. theres 3 of them. one coil appears to have a hairline crack in it
 

wrench 3

Commander
Joined
Aug 12, 2012
Messages
2,108
I was thinking bad insulation on a coil letting moisture in and doesn't dry out until the engine warms up.
 

racerone

Supreme Mariner
Joined
Dec 28, 2013
Messages
36,047
Some testing to do.-----Does the spark jump a gap of 7/16" or more, yes or no ?---How long have you owned this motor and did this problem show up suddenly ?
 

troller59

Recruit
Joined
Jan 26, 2019
Messages
4
was thinking the same about moisture getting in. had the boat about 8 yrs. this problem happened suddenly i believe. will check spark in the spring. its 10 degrees here with a foot of snow. be glad when winter is over. also $30 per coil sounds reasonable
 

wrench 3

Commander
Joined
Aug 12, 2012
Messages
2,108
I had an old Evinrude with distributor mag that quit every time it got damp. The coil insulation was cracked way in the back were you couldn't see it.
 

oldsub86

Petty Officer 1st Class
Joined
Sep 9, 2008
Messages
311
I have had good luck patching coils that have cracks with epoxy.
 
Top