thefishingfreak
Seaman Apprentice
- Joined
- May 12, 2002
- Messages
- 46
my friends boat.
a few weeks ago it felt{to me} like it was low on power and low max rpm arround 4800 max. momentarily, then problem seemed to disapear.
fast forward to the next weekend. my friend took it out over 1.5 hrs on plane to the fishing grounds. 6 hrs trolling. 1/2 way home they stopped to use the head. on power up #4 piston blew up.
this is where I come in as the somewhat mechanicly inclined friend.
I stripped it down, #4 looked like either 1" of the top ring broke? or 1" of the top of the piston broke? didn't look overheated/melted it just looked like a part{piston or ring} failure.
we honed the cyl. installed new piston/rings, deburred the head cover and buttoned it back up. runs super, only problem is it is down 800-1000 rpm max {4200-4400 max} and it sputters slightly on acceleration. with the air box off if you crack the throttles fast it just boggs down.
we ran out of time/daylight today to search for the cause but I suspect whatever it is, is what caused the piston failure.
any tips on what to look for first?
thanks.
a few weeks ago it felt{to me} like it was low on power and low max rpm arround 4800 max. momentarily, then problem seemed to disapear.
fast forward to the next weekend. my friend took it out over 1.5 hrs on plane to the fishing grounds. 6 hrs trolling. 1/2 way home they stopped to use the head. on power up #4 piston blew up.
this is where I come in as the somewhat mechanicly inclined friend.
I stripped it down, #4 looked like either 1" of the top ring broke? or 1" of the top of the piston broke? didn't look overheated/melted it just looked like a part{piston or ring} failure.
we honed the cyl. installed new piston/rings, deburred the head cover and buttoned it back up. runs super, only problem is it is down 800-1000 rpm max {4200-4400 max} and it sputters slightly on acceleration. with the air box off if you crack the throttles fast it just boggs down.
we ran out of time/daylight today to search for the cause but I suspect whatever it is, is what caused the piston failure.
any tips on what to look for first?
thanks.