1981 evinrude 35 not running right help?

Feltnerd

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Mar 8, 2009
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I have a 1981 evinrude 2cyl 35 electric start on a malibu 14 skiff. until recently the motor ran fine. it will run fine at idle and when I rev it with the muffs on in the driveway. when I put it in the water it will run full out up on plane for about ten minutes, then it starts to lose rpm and kick on the transom. it will lose rpm then rev back up then lose it then rev back up until it just shuts off. after it shuts off it wont start for about 5-10 minutes and runs rough and wont get on plane. I have rebuilt the carburetor and fuel pump thinking it was a fuel problem but it didn't change anything just made in run smoother obviously. It also will idle up and down sporadically when in neutral. I am pretty good mechanically I rebuilt an old evinrude 4hp with no problems but this one has me stumped, I'm think the next step would be replacing the coils? pee stream is strong engine seems to stay cool.....help me please?
 

bream master

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Jun 27, 2008
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Re: 1981 evinrude 35 kicks when on plane

Re: 1981 evinrude 35 kicks when on plane

Replace the coils mate,and u should b sweet:)
 

5150abf

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Re: 1981 evinrude 35 kicks when on plane

Re: 1981 evinrude 35 kicks when on plane

Get an OEM manual for it, not Seloc, Clymers or anything on CD, they have procedures to test electrical components so you cna tell what is bad.

You can get one here at iboats or search Ebay btu stay with an OMC manual.

Could be a coil or the CDI, I have heard of them being okay until the heat up then they fail.

Go through your wiring harness too, I have an '81 50 and found alot of the wires were really brittle and the sheath was starting to come off alot of them so I replaced all the wires under the hood.

If you do it 1 wire at a time it isn't bad, just leave a good 2'' tag wire at the big red plug.
 

Feltnerd

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Re: 1981 evinrude 35 not running right help?

ordered new coils, but pulled the top spark plug out and the threads from the block came with it, what should I do?????
 

jasper60103

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Sep 18, 2008
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Re: 1981 evinrude 35 not running right help?

ordered new coils, but pulled the top spark plug out and the threads from the block came with it, what should I do?????


Replace the cylinder head. Check the salvage yards and/or ebay.

I would recommend having it helicoiled but it sounds like that was done before, and failed.
 

Feltnerd

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Re: 1981 evinrude 35 not running right help?

Never helicoiled just became brittle and disintegrated is what it looks like to me, maybe tap and re thread it?
 

jasper60103

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Sep 18, 2008
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2,055
Re: 1981 evinrude 35 not running right help?

Never helicoiled just became brittle and disintegrated is what it looks like to me, maybe tap and re thread it?

Interesting. I guess it's worth a shot if the tap has something to bite into. I used Sav-A-Thread on my '88 30 hp with success. Also, I used Permatex High Temp Thread Sealant for reinforcement. Not sure it was needed, but it could only help. Good luck.
 
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