Yamaha 2 stroke 40hp re-build or not

mmd5

Seaman Apprentice
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Apr 20, 2003
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41
Looking for your advice on whether or not to re-build a 1993 40hp Yamaha. It has a bad cylinder head and pistons are questionable. It does have a completely new (last july)bottom end after hitting a rock ($900.00 paid by insurance co.). I can buy it for approximately $400.00. I would rebuild myself. The current owner has had it since new and has bought a new motor after this one fried. It has been retrofitted to a tiller handle but comes complete with the original controls. I guess I'm wondering what the chances are of a proper re-build for let say $600.00 (parts only). I currently have a 16' aluminum fishing outfit that it would fit nice on.
 

butlp

Petty Officer 1st Class
Joined
Feb 26, 2002
Messages
302
Re: Yamaha 2 stroke 40hp re-build or not

mmd5,<br />It really depends on how much you are going to pay for the motor! If it is cheap and in good condition apart from the problems you outlined then it is worth stripping it down and pricing out the parts required to fix it. As a fall back position you could part it out and sell all the good bits on ebay and make a profit.
 

rodbolt

Supreme Mariner
Joined
Sep 1, 2003
Messages
20,066
Re: Yamaha 2 stroke 40hp re-build or not

hello <br /> if the crankshaft is good then it may be doable for 6-700 dollars in parts.<br />the crank can be rebuilt for about 400 or so sometimes less if its not to bad.<br /> for 1400 or so you can have a completely reconditioned powerhead. the electricals on the yammi are as close to fail proof as anyother outboard.<br /> good luck and if ya need a place to send the crank post again
 

mmd5

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Apr 20, 2003
Messages
41
Re: Yamaha 2 stroke 40hp re-build or not

Thanks for the replies. After obtaining this motor here is what I found. Needs a re-sleeve and new piston on the bottom cylinder. The other two really should be honed and pistons replaced. The crank is fine and its bearings look ok too. Including the above, a carb rebuild, upper/lower crank bearings/seals and a gasket set gets me a new powerhead. I bought the engine for $200.00 and the above is going to cost approximately $800.00. It is a 1992, electric start, no power trim.<br /><br />Am I 'beating a dead horse' on this one?.
 

Dhadley

Supreme Mariner
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Feb 4, 2001
Messages
16,978
Re: Yamaha 2 stroke 40hp re-build or not

Why does it have to be sleeved?
 

mmd5

Seaman Apprentice
Joined
Apr 20, 2003
Messages
41
Re: Yamaha 2 stroke 40hp re-build or not

The cylinder wall cracked just below one of inlet ports. I've taken it to a trusted engine mech. and he says it can be re-sleeved, but he wants to check the block once the sleeve is out just to make sure there is no other damage. <br /><br />I guess my biggest concern is the bearings that are non-replaceable (I believe you have to buy a new crank to get new bearings) on the crankshaft assembly. Although they seem fine and run smooth with no flat spots, I wonder if they got some metal in them when the piston went 'pop'!.
 

Dhadley

Supreme Mariner
Joined
Feb 4, 2001
Messages
16,978
Re: Yamaha 2 stroke 40hp re-build or not

Yep, a cracked sleeve should be repalced. Just curious, sometimes folks arent aware of all the oversizes and resleeve when it could be bored.<br /><br />Good luck!
 

mmd5

Seaman Apprentice
Joined
Apr 20, 2003
Messages
41
Re: Yamaha 2 stroke 40hp re-build or not

I noticed your location. I wish I were in Port Charlotte, it is 36 degrees here and my hands are numb from washing the grease off this thing in my lane.
 

Dhadley

Supreme Mariner
Joined
Feb 4, 2001
Messages
16,978
Re: Yamaha 2 stroke 40hp re-build or not

Lol! I feel your pain! I was in Ohio all last week and never saw the sun. I left Saturday just before it snowed and Sunday my wife and I were on our boat up river soaking up the sun and listining to the NASCAR race.
 
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