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Johnson 150 86b overheat horn just came on

K

Kurt Templin

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" I have what I believe is a 8

" I have what I believe is a 86 year Johnson 150, put it in the water for the first time this year and after several minutes the horn came on, I assume thats the overheat alarm? The motor is pumping water, but it didnt seem very warm. What would be the first steps to diagnose overheating problems?

Thanks! "
 
" PS..the engine was stalling

" PS..the engine was stalling at acceleration, I saw on another Post someone mentioned some V-6/V-8s had a fuel vacumm warning, is that on a 86 Johnson 150? If so, I probably have a anti-siphon blockage..maybe...taking a stab here. "
 
"On your engine, the fuel rest

"On your engine, the fuel restriction warning does exist. However, do not assume that a fuel restriction exists.... check to make sure that your engine is not overheating (keep a eye on it).

(Fuel Anti Siphon Valve)
(J. Reeves)

Many of the later OMC V/6 engines incorporate a fuel restriction warning via a vaccum device attached to the powerhead. If the engine overheats, or if you have a fuel restriction, the warning is the same.... a steady constant beep.

NOTE... Only the V/6 & V/8 engines have the above "Fuel Restriction Warning". The warning horn will not sound on the other models.

The fact that a engine is not overheating, but the warning horn sounds off with a constant steady beep, and that the rpms drop drastically would indicate that the engine is starving for fuel due to a fuel restriction. Check the built in fuel tank where the rubber fuel line attaches to the tank fitting. That fitting is in all probability a "Anti Siphon" valve which is notorious for sticking in a semi closed position. It will be aluminum, about 2" long, and the insides of it will consist of a spring, a ball, and a ball seat. If this valve exists, remove it, knock out those inner components which will convert it to a straight through fitting, then re-install it. Hopefully that cures the problem.

Joe
"
 
" Thanks Joe, I dont have temp

" Thanks Joe, I dont have temp gauges on my
console, how can I check the actual temp? "
 
"On a normal running engine, y

"On a normal running engine, you can lay your hand on the cylinder head or the exhaust baffle plate area (plate between the heads) for quite a few seconds. If they're so hot that you can't touch them or that plate area.... it's running too hot.

There's also "Temperature sticks" that sell for about $12.95 each, as pictured below.

The idea is to mark the engine in the cylinder head area with both sticks. Then when the engine reaches operating temperture, the lower temp stick mark should melt... if not, the engine's running too cold. If the higher temp stick melts, the engine's running too hot (pretty simple).

I'd sell both of the ones I have for $15.00 and handle shipping (in the states) if you or anyone else is interested. (Just click on my name above)



Joe
"
 
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