Before you start tearing into the reeds, put this engine in the water (so it has back pressure) and see if it does this at idle. We had a number of new engines that had a lean condition when run on the muffs but idled perfectly when submerged to normal running height in the water. Please report...
Hey shearpin,
Sounds like you're loaded for bear and have your gray matter deep into this... Have you verified engine temperature, cold shows its ugly head as rich. Does the engine have the correct spark plug heat range? Have you verified compression? Spark with a real spark tester? Just the...
Remove the spark plug, insert a small screwdriver into the hole and make contact with the top of the piston, rotate the flywheel clockwise and let it push the screw driver outward until it reaches the highest it will go, that is static TDC.
Try putting it in the water at the ramp making sure that the gearcase is fully submerged at least 5" above the gearcase joint. See if it pees. I've seen Yamahas that get finicky with flush attachments and not pump water correctly. My 115 SHO needs to have the flush attachment "just right" for it...
I did some further research and in fact, found that there is no shift connector to disconnect. This engine is splined top and bottom of a one piece shift shaft. It has a 1/2 moon spline top and bottom. If you study the exploded views of the gearcase and midsection you can get a better...
It will come apart, I once spent 14 hours trying to remove two gear cases on a pair of 2003 75hp Mercs from Naples, Florida. They had never been apart in 10 years in salt water. I had to pull both powerheads to get the driveshafts free so with heat and a dead blow hammer ,wiggling, wedges and...