1986, 8hp, evinrude,coughs,spits, dies

[1ghunt]

This motor starts on the first pull but will cough, spit and even die after warm up. The cylinders are 92 lbs., new fuel pump, checked spark with tester, cleaned carb 4 to 5 time. It may take of and run at full rpms for who knows how long then will quit completely but restart on the first pull. New fuel in the tank. pumps up tight and remains. pulling the choke a little does no good and makes it smoke. Going to check the cut off switch next for a ground. Any suggestions? Thanks.

 

[iwombat]

Re: 1986, 8hp, evinrude,coughs,spits, dies

Time for a spark test. Make sure the spark jumps 7/16" on both cylinders with a bright blue spark.

 

[1ghunt]

Re: 1986, 8hp, evinrude,coughs,spits, dies

I bought a spark tester, ajusted the gap and had strong spark on both cylinders. I disconnected the ground sid of the cut off switch and taped it up but it made no difference. I won't make a difference if the wire is grounded between the handle and the rest of the engine so I'm thinking of taking that harness out to look at the wires.

 

[iwombat]

Re: 1986, 8hp, evinrude,coughs,spits, dies

If you have a timing light, check to see that both cylinders are firing when they should. Cyl #1 should fire on the timing mark (or close). Cyl #2 should fire 180-degrees off (make a mark on the flywheel for cyl#2). If either is firing when it shouldn't, it's probably your power pack.

I have the same motor and had a similar problem. When the power pack got warm it would backfire on #2 (firing on the #1 timing). I could reproduce the problem by heating the power pack with a hair dryer, and remove the problem by cooling the power pack with an ice pack.


Edit: sorry, missed the "checked with spark tester" comment in the original post.

 

[1ghunt]

Re: 1986, 8hp, evinrude,coughs,spits, dies

I do not have a timing light but would puchase one if I knew what and where. Then I need to know how and where to hook it up. Thanks.

 

[iwombat]

Re: 1986, 8hp, evinrude,coughs,spits, dies

A simple inductive timing light can be purchased at any automotive parts store. You hook it up to a battery source (to power the strobe light) and clip the inductive lead around a spark plug wire to fire the strobe. You can then strobe the flywheel while running to see where the cylinders are firing relative to the crank position.

 

[1ghunt]

Re: 1986, 8hp, evinrude,coughs,spits, dies

Thanks for your help. This is such a nice engine for the 12 foot Valco boat that I have that it is a shame to give up on it. I had exhausted my knowlege of what to do next but that sounds to reason

 

[1ghunt]

Re: 1986, 8hp, evinrude,coughs,spits, dies

Is the electronic module you are speaking od called the shift assist module? I have also noticed that the motor will start whether it is in gear or not.

 

[iwombat]

Re: 1986, 8hp, evinrude,coughs,spits, dies

Nope, it's called a power pack. Follow the leads from the two coils and you'll find it.

 

[huckelberry]

Re: 1986, 8hp, evinrude,coughs,spits, dies

Auto Zone, if you have one near you, will let out a timing light for a small deposit that you get back when you return it. I think advance auto parts also does the same thing.

 

[1ghunt]

Re: 1986, 8hp, evinrude,coughs,spits, dies

I replaced the power pack and the motor starts and runs like a new one. Thanks to everyone for your suggestions and help. It is great to have such a service and the knowledge of so many that have experienced the same problem.