99 50HP flywheel stuck

[Beasley2611]

Motor ran perfect one day. Next day won't start. Traced it to something in power head, not in lower unit. Flywheel will turn 350 degrees and is hitting something internal. No noises, alarms or indication of trouble previous day. It's like something fell off when motor stopped. Took lower unit off an good. Flywheel still hitting. I can't imagine the bottom of piston clamp fell off or backed out enough to hit. Broke cam maybe? Suggestions? Thanks!

 

[Sea Rider]

Welcome to Iboats,

That's a 2 or 4 stroke engine ?

Happy Boating

 

[Beasley2611]

Thanks Sea Rider. It's a 4 stroke. I assume the Pistons should make 2 complete strokes with 1 revolution of flywheel. If so, how could it no hit stoppage at 170 degrees instead of 350? Scratching my head

 

[gm280]

Thanks Sea Rider. It's a 4 stroke. I assume the Pistons should make 2 complete strokes with 1 revolution of flywheel. If so, how could it no hit stoppage at 170 degrees instead of 350? Scratching my head

Beasley, NO, the piston doesn't make two strokes per revolution. The piston only makes one stroke per RPM. If takes TWO RPMs for one complete total intake, power, and exhaust cycle. In a 2-cycle engine it all happens in one RPM.. So you do have something come apart somewhere... Let us know what.

 

[Beasley2611]

Thanks GM. We have to decide to tear down or replace. 1999 motor. Opinions?