gaylamb, thanks for the information about my engine.
I bought the rig about 2 years ago form the 2nd owner,know the 1st owner. The rig was in perfect shape ,never been in salt and low hours on the engine.
Never had a problem ,except some leakage from the lower carb.
This year when I first started the engine , both carbs leaked. Changed out carb needles and plugs, fixed the problem but noticed that the upper carb had what appeared to be fuel stand off at the throat of the carb. Checked plugs and performed a cylinder pressure check. Plugs wet(fuel), cyl. pressure very good. Decided to look at the reeds and sure enough 2 reeds had small pieces broken off and 1 had almost the complete reed missing (found some of the large piece on the carb side of the reed plate). I feel very lucky that the broken reed pieces did not destroy or damage the power head. Replaced with Boyesen reeds and now the engine starts quicker and idles smoother. Did not see any improvement in upper RPM 5300.
Thanks to your history lesson, I now can order the correct repair manual to set idle and timing.
I sure wish I could get a 150 Optimax but that thing would cost more than I paid for my complete rig.
Thanks again.
Bob