ToBrokeforNew
Cadet
- Joined
- Dec 6, 2022
- Messages
- 12
Hello everyone, I'm having an unsolvable issue with my 1989 Mercury 35hp 2-stroke tilt and trim motor. I have been having a specific issue of not being able to go full speed with my motor. The issue I've had is the motor is very finicky. It starts with my rough idle so I adjust the air/fuel mixture screw to adjust the idle so she idles smooth as glass. However when I'm starting the motor cold and I engage the idle advance to raise my rpm to start the motor it only moves the butterfly a little. It will start however it isn't what I have seen in my past motors as a high enough idle, so I will get the motor running and then lower the rpm to get the motor to idle at this point the motor dies instantly. I have adjusted the throttle linkage and spark advance and either it will have to have 2 settings with the air/fuel mixture screw, one for idle and the other for high rpm but it won't run both in one adjustment. So that's super frustrating but it gets worse once I can get it into forward then it will go about 3/4 throttle accelerating then it's like it hits a wall. Once I'm at WOT I might be going 5 mph which I have previously got this motor to run up to 27 mph. Now once I start backing off the throttle to 1/4 throttle it will just shut off. So let me tell you what I have eliminated as possible culprits. I have rebuilt the fuel pump and changed all the fuel lines with automotive rubber fuel lines not that EPA garbage I have a glass see-thru fuel filter before the carb I have completely cleaned it out. I have also rebuilt the carb with new gaskets and needle and seat, I have tested the compression and both cylinders are exactly 150 psi which I called a marine tech and asked if that was too high of compression and if there ever was such a thing and he said no that's really good compression. I have checked to make sure that the throttle blade was going full open and it is. I'm lost I'm not sure what to do now I just cleaned the carb again yesterday, any help would be mush appreciated.
