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J

jmc

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johnson 175 1993 had the boa

johnson 175 1993 had the boat out sat and after a plane the engine would lose power when i went to the primer ball it was soft after a few pumps the engine started but same thing.Possible spin on filter clogged? Would appreciate some help.
 
"If the bulb was simply "n

"If the bulb was simply "not hard" after running, that's normal. If, on the other hand, the bulb had collapsed flat somewhat, that indicates a fuel restriction between the bulb and the fuel supply.

If any leaks exist in the fule line, that would allow the pump to draw air.

If no leaks, and if continous pumping of the bulb allows the engine to run normal, that indicates a faulty VRO fuel pump.

If a flat primer bulb condition exists.....
(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.

The above procedure will cure a restriction problem with the anti siphon valve as stated. BUT, it may also allow fuel to drain backwards to the fuel tank when the engine is not running (siphoning backwards) due to the fact that the carburetors/fuel pump etc are higher than the fuel tank. This condition is not an absolute as the valves in the fuel primer bulb usually prevent this backwards siphoning problem. However.... if this does take place, the cure would be to install a new anti siphon valve.

Let us know what you find."
 
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