Notchcraft
Cadet
- Joined
- Apr 14, 2010
- Messages
- 11
I purchased a boat with a 1994 Johnson 140 HP V4 with a bad cylinder. Got the whole package with a really nice galvanized trailer for $400. I'm planning on selling the trailer, scrapping the boat so the motor will essentially be free after selling the trailer.
That said, the overall motor looks to be in good shape but the top left cylinder is zero compression. Compression is 120 on the other cylinders.The head is off and the piston crown is not damaged but it has some movement in the bore so I think it broke a ring? Possibly stuck a ring then finally broke because the dome of the piston was very carboned up compared to the other piston on the bank. The cylinder has some gouging on the exhaust side, nothing severe. 10 over would probably clean it up. The lower cylinder and piston on that bank looks perfect with crosshatch still perfect in the bore.
The PO said it ran fine then quit on the lake took it home and ran fine on the muffs, took it back on the lake and ran but not at full power. No abnormal noises or knocking, just lack of power. My question is should I rebuild it with new bores and pistons? Scrap it and sell the trim, lower unit etc? Or is it worth it to rebuild? I've rebuilt a couple outboards before but i'm not sure if it's worth rebuilding this motor.
Looking at the cost, the kit is $800 and boring is $75 per hole so I'd have maybe $1200-1400 all said and done in it. They go for about $1500 running and around $2000-2500 fully rebuilt here in MN.
Thoughts?
That said, the overall motor looks to be in good shape but the top left cylinder is zero compression. Compression is 120 on the other cylinders.The head is off and the piston crown is not damaged but it has some movement in the bore so I think it broke a ring? Possibly stuck a ring then finally broke because the dome of the piston was very carboned up compared to the other piston on the bank. The cylinder has some gouging on the exhaust side, nothing severe. 10 over would probably clean it up. The lower cylinder and piston on that bank looks perfect with crosshatch still perfect in the bore.
The PO said it ran fine then quit on the lake took it home and ran fine on the muffs, took it back on the lake and ran but not at full power. No abnormal noises or knocking, just lack of power. My question is should I rebuild it with new bores and pistons? Scrap it and sell the trim, lower unit etc? Or is it worth it to rebuild? I've rebuilt a couple outboards before but i'm not sure if it's worth rebuilding this motor.
Looking at the cost, the kit is $800 and boring is $75 per hole so I'd have maybe $1200-1400 all said and done in it. They go for about $1500 running and around $2000-2500 fully rebuilt here in MN.
Thoughts?