1980 evinrude 70hp no power under load for the first few minutes

[dmaff]

Hi all,<br />I am a newbie to this forum and to boating, for that matter. Just bought a 1980 Evinrude, it starts great and idles fine. Problem is it has no power under load for the first few minutes(it seems to be getting worse). After a while it will sporadically surge for a split second and then will let loose and run fine. I have checked all three carbs and they are very clean. Have also checked the ball and it is very hard when running. Have also put in new plugs which made no difference. It is almost like it has to warm up. Any help would be greatly appreciated.

 

[almost retired again]

Re: 1980 evinrude 70hp no power under load for the first few minutes

Hi Demaff<br />You say that the carbs. look clean, did you take them off and take them apart? If you didn't that is where I would start. It sounds like you have a piece of trash floating around in there, sometimes plugging up one or more of the high speed jets. It could also be one of the coils cutting in and out at high speeds. Just a couple of thoughts that I hope might help.<br />Good luck, and let us know how it comes out.

 

[Firk]

Re: 1980 evinrude 70hp no power under load for the first few minutes

Hey Demaff,<br />I have the same problem.<br />How did you fix it and what was the problem?<br />Cheer's Shane

 

[dmaff]

Re: 1980 evinrude 70hp no power under load for the first few minutes

Still haven't figured it out, I did take all carbs off and looked in the bowls. All were very very clean. I am starting to think it electronic...one of the guys at work suggested an ignition module...might try that next.

 

[KillerJello]

Re: 1980 evinrude 70hp no power under load for the first few minutes

Could it possibly be an issue with the choke, or lack thereof? Im a newbie to boat motors, but have much experience in the small engine (atvs, snowmobiles, lawn tractors, and PWC's) and also lots of experience in the automotive field, but not much along the lines of boat motors yet.<br /><br />May want to ask for a second opinion, but thats what it sounds like to me...

 

[F 117]

Re: 1980 evinrude 70hp no power under load for the first few minutes

when it does this try hitting the choke, if it comes to life would look in to carbs, float level and check jets for junk

 

[dan2003]

Re: 1980 evinrude 70hp no power under load for the first few minutes

Apples to oranges i know, but i got a buddy that had a similar problem on his merc. His turned out to be corrosion on the power pack terminals, and old spark plugs. Cleaned the terminals, put in new plugs, and it ran fine. Just food for thought...

 

[rickdb1boat]

Re: 1980 evinrude 70hp no power under load for the first few minutes

You said you took off all the carb bowels, but did you clean each carb out and reset the floats? Just trying to cover the bases. The jets can get clogged easily, causing your problem. A rebuild kit and thourough cleaning is the best way to service the carbs. Good Luck,

 

[Solittle]

Re: 1980 evinrude 70hp no power under load for the first few minutes

The carbs may look clean and still be packed with crud in the passages that you cannot see. Read here:<br /><br /> http://www.outboardrepairs.com/carburetors/

 

[carmangary1]

Re: 1980 evinrude 70hp no power under load for the first few minutes

I occasionally have this exact problem with my 1972 Johnson 85. I haven't been able to pinpoint the problem but it usually goes away after I clean the carbs and change plugs. <br /><br />In my case, it doesn't rev up when I hit the choke. It usually slows down. <br /><br />Good luck.

 

[OBJ]

Re: 1980 evinrude 70hp no power under load for the first few minutes

Hi dmaff....<br /><br />When you say "it runs fine", does that mean the problem doesn't occur anymore or, after you shut down for a while, it will occur again.

 

[dmaff]

Re: 1980 evinrude 70hp no power under load for the first few minutes

Hi Jim,<br />That is exactly it. Once it kicks in for good it runs fine until it has been sitting for a few hours...than it occurs again. I'm just not sure that the carbs are the prob. If there was gunk in the jets once it lets go wouldn't the gunk be gone for good. Thanks for all the replies it really is greatly appreciated.

 

[dmaff]

Re: 1980 evinrude 70hp no power under load for the first few minutes

Went out again today and had the exact same thing happen...I pushed the choke while it was running and it would nearly stall the engine. Not sure what this means but am guessing it is pointing further away from the carbs

 

[ob]

Re: 1980 evinrude 70hp no power under load for the first few minutes

Check all of your igniton components for clean and tight connections.Also all of the engine ground wires.If bumping the primer button causes the engine to die after it has been run a bit that is normal as it is flooding the engine.<br /><br />Also if your throttle controls are equipped with the lanyard kill switch that uses the rubber cap to keep the button depressed,the rubber cap is prone to stretching out and causing intermittent grounding of ignition.