120HP Evinrude Smoke at Start - Help

mcneidm

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I have a 1987 120HP Evinrude that smokes pretty bad when I choke to start it. Other than that it runs pretty good after it gets going. THe only other comment I could say it really never has liked running too long at idle or low speeds. Any ideas?
 

JB

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Re: 120HP Evinrude Smoke at Start - Help

Howdy, Mac.<br /><br />Those old bulldozers smoked a lot when new and never did like to idle for long periods.<br /><br />When you store her any fuel in the float bowls starts to slowly evaporate, leaving an oil-rich mix. When you start her up you may be burning off a carb full of oil-rich mixture.<br /><br />There is no way I know to make them idle for long without loading up or even fouling a plug or two.<br /><br />At age 25, she has earned the right to be cantankerous.<br /><br />Red sky at night. . .<br />JB :)
 

mcneidm

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Re: 120HP Evinrude Smoke at Start - Help

Actually its a 1987. Transposed the numbers the first time.
 

JB

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Re: 120HP Evinrude Smoke at Start - Help

OOPS! Forget what I said above, Mac.<br /><br />If you still have the VRO connected, I would suspect it is putting in too much oil, or that you are burning off the fuel in the carbs when you shut down. <br /><br />If you disconnect the fuel line and then run the carbs "dry" (a common but risky practice in the old days) the oil keeps pumping and you will have an oil rich mixture on start up.<br /><br />Crossflow OMC V4s always were snotty about idling for long periods unless you pop her into neutral and rev her up (til the smoke abates) once in a while.<br /><br />Red sky at night. . .<br />JB :)
 

mcneidm

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Re: 120HP Evinrude Smoke at Start - Help

JB<br />Is there some adjustment that can be made to slow the oil flow during start up? Two years ago the engine didn't start like this, mostly just started last season in Illinois. I was going to take the boat in to get the trim worked on before dropping it in down here anyway, just was more curious what I would be getting into with the smoke. I just moved to FL a week ago. Trim is a little sluggish, internal leak, or pulling air I think. <br /><br />You mentioned above that if I disconnect the fuel line and run the carbs dry I'd have a oil rich mix on start. Looks like that is what I have already, or did I misunderstand you? <br /><br />Thanks,<br />DM
 

JB

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Re: 120HP Evinrude Smoke at Start - Help

Hi Mac.<br /><br />If your fuel pump is weak you might get too much oil, but after she warms up, everything is okay. Right? I am at the limit of what I know about VRO. I always disconnected it and ran premix.<br /><br />What I meant was that if you disconnected and ran the carbs dry, that could account for the smoke. If you don't do that it is irrelevant. It is not a good idea in any circumstances and a very bad idea on oil injected engines.<br /><br />Red sky at night. . .<br />JB :)
 
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