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1981 90 HP Excessive smoke at start up

E

ed_in_va

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"When running this motor at hi

"When running this motor at high speed cruise for 45 minutes and then stopping for a break... upon restarting the motor I get excessive smoke...Real Bad... enough to be of great concern.

Can someone suggest a course of action?

I would guess I should remove and clean the carbs and check float level and condition.

Can anyone offer a method as to how to inspect and recondition the carbs on this motor? Are the jets adjustable on this motor?

This motor has autolite spark plugs in it. Is there a different, preferred spark plug to be using on this old girl?

Thanks for your help and input...Ed in Va."
 
That information about VRO sys

That information about VRO systems probably isn't relevant to your specific problem since your engine is a 1981 you probably don't have VRO. Looks like OMC didn't have VRO systems till 1984. Sorry about the mis-information.
 
"Thanks Gary and Rollie,

"Thanks Gary and Rollie,

Yes ...that 81 model is a manual mix on the fuel/oil ratio.

A compression test probably is a good place to start. Seems like a cold motor compression test would be proper.

Thanks Ed in Va."
 
"If idling ok and full power,

"If idling ok and full power, I think I would leave the carbs for the time being, even the comp tests.
You are obviously pr-mixing, but are You precise in the pre-mix or do You add a little extra just to be safe?
I prefer running 1,5-2% rather than 2+%, unless You do a lot of water skiing.
Switch the plugs to Champion L/QL77JC4, and run a round of sea-foam/engine tuner.
Check out the recirculation system and particularly the check valves in the intake manifold."
 
"Thanks Morton,

I have b

"Thanks Morton,

I have been using 1 pint of oil for each 6 gallons of gas. That must equal a 48:1 ratio.

1.5% ratio would be .72 pint per 6 gallons. 2 % would be .96 pint per 6 gallons.So far no skiing... just pleasure boating.

I'll get the plugs you recommend. The Sea Foam I'm familiar with comes as a liquid fuel additive in a pint can from Advanced Auto Parts Store. Is that the same as you suggest? I have seen references to a spray version of Sea Foam.

The recirculation system and check valve inspection will be interesting to me.

Thanks Morton ...Ed in Va."
 
"Personally I always used the

"Personally I always used the Engine Tuner from OMC, but it seems that sea Foam more or less does the same. Most important get the carbon/soot out of the engine and exhaust system."
 
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