Grease? gotta know in next hour

[Sonosailor]

I have an SD20 Yanmar saildrive removed, and notice that the spline shaft (the portion that sticks into the drive train of the engine) is not lubricated or greased, and neither the service manual nor the installation manual says anything about it. Should I grease the spline shaft before reassembly?

[Pete7]

Can't think of a reason not to as it will make taking it apart in the future easier and hopefully discourage fretting on the splines. A nasty problem with some volvo shaft gearboxes.

Pete

[HappyMdRSailor]

I've never assembled ANY splined shaft without a generous dab of good old fashioned thick tube lube (grease)

[Sonosailor]

Much appreciated. I'll post some info on changing the diaphragms when I can.

[ontherocks83]

Originally Posted by HappyMdRSailor

generous dab of good old fashioned thick tube lube (grease)

Happy don't confuse the poor man, he's talking about Marine grade grease, not the stuff left over from your night stand

[reed1v]

Originally Posted by ontherocks83

Happy don't confuse the poor man, he's talking about Marine grade grease, not the stuff left over from your night stand

Yup. Need marine grade. However, grease may not be the way to go. If you grease a winch, it will bind up and be hard to crank. Suspect the same with this situation.

[Blue Stocking]

If the female is vented at the far side from the entry, heavy oil is ok to lubricate. If it is NOT vented and the male spline displaces the atmosphere on the way in, you will have a VERY DIFFICULT ( if not impossible ) time extracting against the vacumn seal created by the grease next removal. This is not conjecture but hard experience speaking.

[reed1v]

Originally Posted by Blue Stocking

If the female is vented at the far side from the entry, heavy oil is ok to lubricate. If it is NOT vented and the male spline displaces the atmosphere on the way in, you will have a VERY DIFFICULT ( if not impossible ) time extracting against the vacumn seal created by the grease next removal. This is not conjecture but hard experience speaking.

Yup, btdt. Hopefully he is only talking about a dab of lubricant. Best he talk to a real mechanic of these engines. Suspect it does not need additional lubrication.

[hellosailor]

Just wondering, if the concern is to prevent the metals from sticking in the future, if antiseize might not be better than plain grease. You can use even less of it, and still prevent the metals from sticking.

[reed1v]

Originally Posted by hellosailor

Just wondering, if the concern is to prevent the metals from sticking in the future, if antiseize might not be better than plain grease. You can use even less of it, and still prevent the metals from sticking.

Depends on how much heat is generated. Some lubricants and zinc compounds will ignite with enough heat. Others will turn to solids, much like churning milk into butter. Which is why he should go to a real mechanic that knows those engines to find out what to do, or not do. An internet forum is not quite the place to risk your life.

[hellosailor]

Well, the unreliable manufacturer's MSDS on the internet for Bostik NeverSeez says it contains no zinc, just aluminum and mainly copper. And the flash point is 475F.
Some other products contain nickel. Flash points vary as well.


Of course that's why Autozone won't sell lubricants to anyone under 21, with or without parental consent and two forms of government photo ID.


Dangerous stuff, grease and antiseize.

[reed1v]

Originally Posted by hellosailor

Well, the unreliable manufacturer's MSDS on the internet for Bostik NeverSeez says it contains no zinc, just aluminum and mainly copper. And the flash point is 475F.
Some other products contain nickel. Flash points vary as well.


Of course that's why Autozone won't sell lubricants to anyone under 21, with or without parental consent and two forms of government photo ID.


Dangerous stuff, grease and antiseize.

Sniff, sniff.

[Jim Cate]

Originally Posted by reed1v

Depends on how much heat is generated. Some lubricants and zinc compounds will ignite with enough heat. Others will turn to solids, much like churning milk into butter. Which is why he should go to a real mechanic that knows those engines to find out what to do, or not do. An internet forum is not quite the place to risk your life.

Reed, just what is the source of the heat that you are worrying about? This is just a splined shaft sticking through a splined socket. There is no relative motion, no friction, no combustion, no heat generating mechanism involved. The grease's sole role is to make assembly and disassembly easier. Very little risk to life or limb.. only to your imagination.

Jim

[HappyMdRSailor]

Originally Posted by ontherocks83

Happy don't confuse the poor man, he's talking about Marine grade grease, not the stuff left over from your night stand

One heckuva compliment! ... Or again, are we talking simply a large container...

Originally Posted by hellosailor

Just wondering, if the concern is to prevent the metals from sticking in the future, if antiseize might not be better than plain grease. You can use even less of it, and still prevent the metals from sticking.

Antiseize has it's place for sure, and I probably use it more often than most...

But... I wouldn't use it here... It would tend to dry out and get clumpy

[seabreez]

Originally Posted by Sonosailor

I have an SD20 Yanmar saildrive removed, and notice that the spline shaft (the portion that sticks into the drive train of the engine) is not lubricated or greased, and neither the service manual nor the installation manual says anything about it. Should I grease the spline shaft before reassembly?

Definitely grease (marine) it not excessive but coat it to prevent rust and make it easier to remove in the future. I hate rust!