No power on a late 80's 115 Mariner

[commodoreswab]

Ive been having some issues with my boat that I typically use 2-6 times a day (our tender) and she is running a late 80's mariner 115 tower of power. I am almost positive the problem is with the carbs but would like to get some second opinions. The symptoms are that when I give her throttle in gear she simply dies. Coupled is the fact that if I run it up in neutral a couple time (clearing out the engine) then shift her into gear she sometimes takes off and runs great. If she is running on plane and I idle down same problem, rev her up then she will take off. The carbs have been cleaned, I replaced 1 float unrelated to the problem (dropped the little spring overboard working on it) and I just replaced all the inlet needles and have been working to adjust the float levels. After replacing the needles she ran fine but died as soon as placed into gear. Lowering the floats levels I was able to make it back to shore although unable to get her on plane. The fuel pump was replaced about 18 months ago and pumps up pleanty of pressure. I have a water seperator/filter before the engine and a clear filter on the engine after the pump where I can visually see she is getting good clean fuel. The rubber mounts holding the aluminum shroud are busted and I will be replacing those, they may have been hindering the linkage but moving the cowl to insure the linkage is clear while running did not change anything. Opinions???

 

[Chris1956]

Re: No power on a late 80's 115 Mariner

It is likely the carbs are dirty, mis-adjusted or both. Dying while trying to accelerate is a symptom of too lean of an idle mixture.