how much torque when installing lower gearcase on yamaha out

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I have never herd of a specific torque I just go until they are as tight as I can make them with out fear of snapping one if that helps, I remove the lower unit every year now.
 
FYI, I can get the torque from the OMC factory service manual I have on hand if desired and since Yam stole part-for-part that basic OMC design (yes, there was a lawsuit) the value should be the same.

But note, you should goop up the threads on ANY lower unit bolt, after cleaning them of course, before re-installing. The best thing to use is not a grease, but the gaskett sealing compound.

Also, IMHO there is no practical need or benefit to removing the LU itself every year. For what? A look see? I don't get it :| ... FWIW I do my full waterpump services every 2 or 3 seasons depending on use. If not taking off that 2nd year, I will remove the bolts 1 at a time and clean & re-goop, then re-install.
 
i have a few reasons I remove mine every year, first one is over the past few years I have seen several cases of guys having a heck of a time getting the lower unit off after not removing for 2 or 3 season, in once case with a f225 Yamaha the guy I know needed 5,000$ in work done after trying to remove the lower unit because it was froze on (2005 motor) , the second is its so easy to remove I would much rather have it sit in my heated garage all winter then sitting out in the nasty cold. Just my opinion.

And yes definitely grease the bolts I do it every year.
 
Thanks for help.I always left on and had serviced.But removed myself this year because of water leak in gearboxl that was not fxed last season by mechanic that stated presure test was ok.So I removed and had seals replaced and pump AGAIN(hopefully fixes).Bolts were tight to get off and someone told me torque is 30lb,feels soft ,and bolts were covered with gear lube but should clean (brake cleaner) use lock tight when reistalling,not sure if i should lube over.Either way ,not a hard job at all,just want to do it right.thanks great website/ Steve .(gotta take a pic of my baby 2310 to post)
 
Definitely don't Loctite those bolts. That's probably worse than putting nothing on them. There's already a lockwasher on each if I remember correctly.

I just dab a little anti-seize on mine and snug them down. I make 'em pretty tight, but not so tight that I run the risk of breaking a bolt or stripping the threads. I have no idea how tight they actually are.

If you had water in the lube after a pressure test, there's a good chance your problem was related to the gaskets on the drain and fill screws. ALWAYS replace those w/ new every time you crack them open.
 
For my 1999 Yamaha 200, lower unit torque is 29 ft*lbs or 40 Nm.

-- Tom
 
Thanks for everyones help.I started with a torque of 25lbs then finshed with 35lbs after reading up a little and it seemed to be perfect.I did use a litltle locktight on bolts on friends advice,hope it wasnt wrong after reading some replys.I ran engine on hose in driveway and was running hot after some time.I never had this problem before and changed thermostats,Still hot.Began to panick and spoke to several marine mechanics who stated Yams are famous for getting hot on garden hoses because there is not enough water pressure ,SO VERY SCEPTICAL I towed her down to ramp and put her into the great south bay and ran for a hour and no problems.Crisis solved for me .Lesson learned. Steve !
 
fishing818":2rfxfefk said:
I did use a litltle locktight on bolts on friends advice,hope it wasnt wrong after reading some replys.!
It was ... I'd remove it. Gasket sealing compound is what is used.
 
Not to beat this horse any more, but keep in mind Loctite is a manufacturer, and not just a single product.

Loctite 572 is the recommended sealant for the lower unit bolts in the Yamaha shop manual. If you do some Googling you'll find that 572 is a medium strength thread sealant designed for coarse metal fittings.

Loctite's thread locker products are high-strength adhesives used for locking bolts in place and require much more force to break free.

So it really depends on which Loctite product you used -- hopefully its of the sealant variety.

-- Tom
 
Had the same problem last year when I ran mine on the hose, you have to make sure the muffs are seated just right over the intake grate on the lower unit
 
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