# For the marine mechanics out there!



## huntingbuddy (Sep 10, 2007)

Took the boat out on strawberry today for the first fishing trip of the season, but something went wrong. The trip was going great everything was working great after bringing it out of storage till towards the end. We were motoring to a new spot when I stopped to check things out. When I went to go back to full throttle the motor wouldn't go past 2,500 rpm's full throttle is around 4200. We were crawling. I have no idea what is wrong with it. There is was nothing stuck in the prop, the engine idles just fine in neutral, and when I rev it up in neutral I can get to the 4,200 rpm's no problem. However when I put it in gear 2,500 rpm's max. Any idea's on what the deal is? I am perplexed!


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## outdoorser (Jan 14, 2013)

Had that happen last year. If I remember right, the spark plug wires were on the wrong plugs. If I don't remember right, it wasn't that and but it was mis-timed.


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## outdoorser (Jan 14, 2013)

Try one of those things and let us know how it goes.


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## DallanC (Jan 13, 2009)

I'm going to assume an inboard engine. There is a interrupter that will make the engine miss to lower rpm's when you shift it into gear, sometimes the switch on the shift linkage "Sticks" making it miss when in gear. I had this issue with my boat once, it can also happen if your shift cables get worn down.

Personally it sounds like your carb has got some crap in it. Get the model # off it and get a rebuilt kit online then spend a quiet sunday afternoon disassembling, cleaning, and putting it back together.

Try running some fuel with a rich mixture of seafoam in it?


-DallanC


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## huntingbuddy (Sep 10, 2007)

Sorry I should have given a little bit more info. The motor is an old 90 hp mercury outboard, I am talking 1981 old. Right now I don't have immediate access as it is up at the cabin, but next time I go up I want to work on it and get it fixed. I want to think something is up with the gears, because it will idle fine at 4000 rpm but trying to get the rpm's up that high when in gear won't work.


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## bwhntr (Sep 12, 2007)

Sounds like a shift cable issue... I would start with that.


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## pheaz (Feb 11, 2011)

Clean the carb sounds ethanoled up. Motor is running lean when under load and cant intake enough fuel.. Seafoam is your friend especially at the end of the season.


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