Yamaha 40 Failed Lower Unit

86RinkerV153

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1986 lower unit completely gone, powerhead and controls like new. Really struggling to find a decent lower for under $500. Any suggestions?



 

mphelle8vld

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Mod EDIT: Send a PM, offers arent permitted in the open forum
 
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86RinkerV153

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I had the motor running with the muffs on and it acted like it seized, traced it down to the lower being locked up. Would not shift into neutral, very difficult to turn and making a grinding noise.

With the muffs on, water flows out of oil fill hole. I've decided to take off the oil pump base in hopes that I can see inside and learn more about what might be going on but I'm having a really rough time getting it off.

Does anyone have any ideas as to what may be going on or whether this lower is repairable?
 

99yam40

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you will have to take it apart to find out what all is wrong with it before you can get an idea of what needs to be done and what it will cost

by the way there is no oil pump on the lower unit

get a service manual to see what needs to be done to get the lower apart to inspect everything.

my guess is you put it away with water in the lower unit and bearings and gears rusted up
 

86RinkerV153

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you will have to take it apart to find out what all is wrong with it before you can get an idea of what needs to be done and what it will cost

by the way there is no oil pump on the lower unit

get a service manual to see what needs to be done to get the lower apart to inspect everything.

my guess is you put it away with water in the lower unit and bearings and gears rusted up

​I think that is what happened, looks like deterioration in or near the water pump base was passing water into the gearcase. Was able to get that removed now dealing with removing the bearing, its stuck pretty good and not wanting to damage the area around it. After I get that removed will the drive shaft lift out, or does that require disassembly of the prop shaft section?

​By the way, I meant water pump base not oil pump base in that previous post.
 

99yam40

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there will be a nut on the end of the drive shaft that will need to be removed to get the drive shaft out.
so prop shaft has to come out to get to that nut.

looks like you broke the housing and left part of it in there. not sure how to get that out.
cutting and drilling without harming the case will be interesting.
there are 2 seals between that housing and the gear case that should keep water out and oil in

service manual will have steps and tools needed to do most jobs
 

86RinkerV153

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there will be a nut on the end of the drive shaft that will need to be removed to get the drive shaft out.
so prop shaft has to come out to get to that nut.

looks like you broke the housing and left part of it in there. not sure how to get that out.
cutting and drilling without harming the case will be interesting.
there are 2 seals between that housing and the gear case that should keep water out and oil in

service manual will have steps and tools needed to do most jobs

Thank you, got the housing piece out and the seals. Now struggling to get the weird nut off the housing to start removing the prop shaft assembly.
 

99yam40

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If you have to, drill holes in it at different places and cut the nut and pry out, buy a new one if you put it back together
 

86RinkerV153

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If you have to, drill holes in it at different places and cut the nut and pry out, buy a new one if you put it back together

Good call. If things look repairable inside I'll get the manual but not wanting to spend anything until then so I appreciate the tips. Is it fairly straightforward getting the prop shaft assembly out ofter that, or is there some tricks to it?
 

86RinkerV153

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As predicted, this is gonna be a battle at every step. Got the first prop assembly nut off, now I'm looking at this key and wondering how it could possibly be removed. Help!

 

86RinkerV153

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Nevermind, just learned the retainer pulls straight out. Amazing what these forums can teach you.
 
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