1991 yamaha 150 rebuilt lower unit question

[danielp6378]

Will my service manual for my motor include help on this? How would I learn what parts I need to purchase for my lower unit? Are thise kits or part by part basis? Is this more than a shade tree mechanic can do? I've done clutches, auto transmissions, and the like. Never done marine to this level, but looks less complicated than the power head.

I've order a cd manual for my specific hp/model.

Told by the mechanic tooth broken, and need complete rebuild at 1500 to 1700 bucks. Motor has ran great up to this point.

Is it possible to hire a mechanic to inspect my work before I put it all back together, or is that a pipe dream?

Thanks for the advice.

Daniel

 

[finlay]

Re: 1991 yamaha 150 rebuilt lower unit question

if i was you i would price up a new gear box or a second hand gearbox. there are special tools required to successfully rebuild a gear box.. You have to set the pinion height and the forward and reverse gear have to be set as well...this is done buy spacing the gear in or out by the use of shims, and to check it you need a dial indicator and you need a special tool and puts pre load on the prop shaft.

as a marine mechanic my self i would a aliment to check someones gearbox because him checking it would make him responsible for the life span of the gear box.... but thats just me...

i would recommend that you get a new or second hand gear box it will be alot easier

 

[diveguana]

Re: 1991 yamaha 150 rebuilt lower unit question

Where can I purchase the tools needed for Yamaha lower unit disassembly. I already have the regular puller and dial indicators and the service manual .

I just need YB - 34447 cover nut tool and YB-6207 bearing housing puller .

Thanks

Troy

 

[yamamarinetech40]

Re: 1991 yamaha 150 rebuilt lower unit question

You ain't listening....even old hands don't wanna rebuild these, it's very very tideous work, not many do it well...your chances are slim to none of a proper job....you can purchase the tools from KENT MOORE, they supply Yamaha tools....being a mechanic isn't enough, you have to be schooled in these or you'll screw it, man. Cheep used ones are available(lower units)

 

[diveguana]

Re: 1991 yamaha 150 rebuilt lower unit question

Thanks for the advice. I am in a remote location and I would like to try anyway. I cannot find a link anywhere for the tools through the Kent Mooore search on Google. Anybody know where I can get the cover nut tool ?

I have some experience with OMC lower units and I have the bearing housing pulelr for this and it looks like I can use this to pull the bearing housing once I get the cover nut off. I think I can do it or at least give it a good try

Thanks for any advice on where to get this tool YB 34447

Troy

 

[yamamarinetech40]

Re: 1991 yamaha 150 rebuilt lower unit question

ok,then...I should have said Kent Moore by SPX Brand...search under 'kent moore spx and it'll come right up. Good Luck.

 

[yamamarinetech40]

Re: 1991 yamaha 150 rebuilt lower unit question

ok, followup...looked at site....see, I've always ordered as dealer(Yamaha) so now I see you'll probably have to get a dealer to order, but as they may not want to, you may have to call Yamaha to let dealer know it's ok to sell you this....don't know. Yamaha isn't even listed on site...Mercury is but you have to be....a dealer.

 

[JUSTINTIME]

Re: 1991 yamaha 150 rebuilt lower unit question

yep need to be a dealer to order or have a wholesale licenses

 

[rodbolt]

Re: 1991 yamaha 150 rebuilt lower unit question

actually the best puller for the bearing carrier is the OMC v4-v6 puller and oxygen/acetlyne.
the pinion height can be set at any dealership without the rest of the case. you will need the shft,thrust bearing,housing and pinion gear.
the lash checking tool is less than 10 dollars and the only tricky part is the gearcase has to be upside down to check it.
make sure you use the factory service manual as it has a decent explanation of the + and - marks located under the trim tab pocket.
with all the F,P and R + and minus marks and all the new gears and bearings,including the races, the shimming can be done without the actual case.
once the case is assembled is where you have to have the lash indicator and some gear tooth marking paste.
I use the stuff from a local GM dealer that is yellow.
gears are gears we dont care if its a lathe headstock,a truck tranny or a gearcase.
if the tooth contact pattern is correct and the lash is within spec it lives.
rebuilding gearcases is like rebuilding powerheads.
its not hard it just requires a working knowledge of what is happening.
the tooling just makes it easier.
even most techs I deal with are scared poopless about rebuilding cases and powerheads.
problem now is at 85 dollars an hour (in my area) and the cost of the parts we are usually very close to the cost of a reman unit or even new and all we do is order it up and install it.
to do your case,depending on saltwater corrosion, your looking at 4-6 hours minimum.
some of the volvo DP cases and the bravo 3 cases I have spent 11-15 hours playing with rolling torques,gearlash and tooth contact patterns and usually I simply dont have that much time to spend on one boat.