1987 evinrude 40 vro running issue

[travis050392]

The motor seems to be running fine at first when out on the water. Once it gets hot and I kill it to fish a little I have trouble starting it back up and it then only runs on one cylinder. I pulled the plug on the top cylinder and it looks fouled I’m thinking the coil pack goes out once it gets hot any ideas?

 

[oldboat1]

Not a bad guess -- coil or a power pack. See if the motor is getting too hot (aside from ignition parts over heating). Use an infrared gun (need a temp well under 160F), or test the top of the head with the heel of your hand. Too hot to touch is too hot to run.

 

[ct1762@gmail.com]

My 1982 60hp runs about 170 degrees at idle in warm water, cooler on top end of course. But this sounds like a fuel issue. The carbs might need a clean , or the float is getting stuck,and test those coils with an OHM meter.

 

[jakedaawg]

Once it's hot and screwing up do an open air gap spark check. Disagree with fuel issue based on description. If it runs fine cold heat doesnt generally contribute to a fuel issue in these motors.

 

[ct1762@gmail.com]

that's true! It's hard to tell without having it infront of us with just a description. Is it consistently doing this or "most" of the time?

 

[oldboat1]

Travis -- For Jake's suggestion, use a tester like this:


The object is to measure spark to test the strength of your ignition system. If you get some info on the temp issue, post that. Again, 160F or more is too hot, and means there is a blockage (silt or salt, depending on where you boat), or you are due for an impeller change and possibly a new thermostat.