Johnson 1993 115 crossflow shuts down when decelerating

[acbill]

I have a 1993 Johnson 115hp crossflow outboard that shuts off when I throttle down. Starts right back up but shuts down when I slow from wot. Antbody heard of this before? thanks

 

[emdsapmgr]

Is the idle rpm too low to sustain the engine when idling in forward gear?

 

[acbill]

it idles smoothly at around 600rpm normally in neutral. I will adjust it up a bit and try it in gear and see if that helps. it does idle without stopping in gear though. only when I back off the throttle quickly does it stall. thanks

 

[thumbnut]

I had a johnson that did the same thing. Chased it for awhile. Turned out the fuel pump was slowly deteriorating to the point it was letting the fuel level drop in the float bowl just enough it would run full blast with no issue but was too low for the low speed circuit to pick up fuel. Squeeze the primer bulb as you slow down. If it runs okay, you know what is wrong. Maybe..

 

[acbill]

Sometimes the bulb goes flat and it takes a lfew minutes to pop back out to a squeezable condition. I removed the anti siphon ball from the gas pick up in the tank and replaced the bulb but it still does it occasionally. All hoses and filter is good with no leaks. I don't get it?

 

[racerone]

That means one thing and only one thing.----When a bulb gets sucked flat there is a blockage in the fuel supply line or tank vent..------Check / replace the hose.----Also run with a known to be good hose and portable fuel tank as a test !

 

[acbill]

can a water separator filter restrict flow?

 

[racerone]

Test run with a known good hose and a portable tank.

 

[emdsapmgr]

Sometimes the ball valves inside the hose bulb go bad and won't flow fuel. Also, if the arrow on the bulb is slanting downhill in the splashwell of the boat, it can affect an older bulb. (arrow needs to point in a generally "up" orientation... Try another hose or replace the squeeze bulb.

 

[acbill]

OK Thanks. I'll try a portable tank with hose next saturday and get back with results.