engine dies past idle

1989 Yamaha 9.9 . I removed and cleaned carb . There were flakes in bowl and debris on main jet intrance .Thought I had it licked . Same thing . Starts fine , idles evan at fast idle fine . Put in gear and runs fine till I start to open it up and then dies . Pumping fuel ball does nothing . Pulled fuel pump and checked for diaphram leakage and checkvalve ops ok . Replaced fuel line with clear from fuel filter to carb so I could watch . There is always a 2 inch section filled with air at bottom of loop before carb intake . Haven't checked valve adjustment yet and plan to do compression check next . Flywheel seems hard to turn by hand with spark plugs removed , although I don't know how it should feel . My fear is the engine has been running too lean with partially plugged main jet and caused powerhead damage .Thanks in advance for suggestions .<br />Cap'n One Aye

Re: engine dies past idle

do the carb again<br /> its still plugged most likly. they are touchy lil buggars. but the spark and compression test are always done first. only then can you isolate the problem.

Re: engine dies past idle

Thanks rof the reply Rodbolt . I will pull the carb again . I just did the comp. check .<br />both cylinders were 97psi cold , 87psi warm , at least as warm as you can get an engin at idle for 5 min. The manual says 114psi is min. for this engine . Should I worry ?

Re: engine dies past idle

never seen a spec on it but what your looking for is they are about equal within a 10 psi range. will it accelerate if you play with the choke while throttling up ?

Re: engine dies past idle

Rod bolt , I pulled the carb again and found I had installed the main nozzel cut out facing the funnel instead of the intake manifold . Would this cause my problem ? <br />Thanks ,<br />Cap'n One Aye

Re: engine dies past idle

You were right Rodbolt .I didn't clean the pilot jet the first time because it was hidden under a plug . Run's fine now .<br />Thanks !<br />Cap'n One Aye