Re: repowering 150 Yamaha OX 66
 

DI, sounds like a pretty sweet deal to me...as always when buyin' used motor (I did), look at compression test numbers and lower-unit oil... ;) :D...if those look good, then GO FOR IT!!... ;) ;D 8)...

Re: repowering 150 Yamaha OX 66
 

I talked to my yamaha dealer and he says the OX has something to do with the altitude adjustment. He's got a 2001 Yamaha 150 carb for $5,995 installed I would need a control box for another $300 since i run a 200 johnson, looks like you got a good deal. Good Luck with it. Ck. compression and lower unit. Watch them do it if they let you and learn. Knowledge is a great thing... but dumb and lucky works too. Guess i'll just run mr. johnson till it dont run no more.

Re: repowering 150 Yamaha OX 66
 

Gentleman thanks for your input and support.

Re: repowering 150 Yamaha OX 66
 

Well DI, the "input and support " we got pleanty of around here...It's the "Gentlemen" thing you'll find rare as an equitorial iceberg :)...

Re: repowering 150 Yamaha OX 66
 

Those Yamaha motors are great, but don't give your merc away (unless you want to send it to me!!).

Did the mechanic tell you which cylinder isn't firing?

Shouldn't take more than 30 minutes troubleshoot that problem and fix it (assuming you have the parts).

Start at the plug (that isn't firing) and trace the connection back.

Things it could be.
1. bad plug
2. plug wire
3. Coil
4. Bad switch box (1,3,5 or 2,4,6)
5. Corroded wire or lose connection b/w the switchboxes and the coil.

Assuming your compression is normal around 125 psi in all 6, I'd say fix the Merc (don't forget the yank the oil injection if you do).

Re: repowering 150 Yamaha OX 66
 

There was more bad news that I should have put in the post. There were several leaks that indicated the head had problems and judging by the corrosion it had been sometime since anyone had looked at it. The lower unit appeared to be dripping and the trim tabs would go up but not down. Had I known you were interested in the engine I certainly would have offered it. The Yamaha has been mounted and I should get the boat back tom. to get cleaned up and ready for the water in a few weeks.

Re: repowering 150 Yamaha OX 66
 

Well Dunc . . . you'll love the new motor!! It's a bit more fuel efficent than the Merc Blackmax 200 :)

Re: repowering 150 Yamaha OX 66
 

Sorry Llabi, yes its the first thing I noticed. I had to double check my serial number to make sure they didn't accidently give me a 4 stroke ;D