115 hp (4 cyl 2 stroke) Dies on deceleration

[watersportsguy]

Hi, I have a 97 OMC 115 hp (115TJEUC) 4 cylinder 2 stroke. I bought it used and the owner said he was having "fuel issues". He didnt really say how long the engine had been sitting. It runs rough at idle . Somewhat an occasional misfire. If you nudge the accel it will putt along. Slam it forward and it will run at top speed without any apparent issues. When the throttle is pulled back to about 50% it will die as if the ignition was switched off. Most of the time no sputtering. If I catch it just right and slam it fwd again it will bog down a bit and proceed to run at max again. Gradual acceleration will result in stalling as well. I don't have a lot of experience with boat engines but it seems almost like an auto carb without a dampener to control the rate of butterfly closure.(when it stalls). (there is a lot of oil burning at startup/idling for quite some time)

Thx

PS I haven't checked compression/timing yet....tools at home

 

[bob johnson]

Re: 115 hp (4 cyl 2 stroke) Dies on deceleration

my opinion would be that any motor that is running GREAT at full tilt (WOT) probably doesnt have any serious issues( like poor spark or low compression).....might be a timing issue...... or a float issue...but hose are just guesses


good luck

bob