Outdrives!! stainless steel screwed into aluminium alloy.

[kashurst]

Fortunately not stuck, but I have cleaned up the parts. I was going to use copper grease, but it's going into water for a long time.
What is teh best grease to use with stainless steel into aluminium kept underwater?

Thanks all.

 

[tico]

I'd avoid copper grease due to electrical potential.
Probably best to go for a Teflon (PTFE) grease to try to get isolation
Vyv Cox is your man

 

[SC35]

I use this:



Quicksilver 2-4-C Marine Grease with PTFE 8oz

 

[Momac]

I use white marine grease on the prop splines and also on the driveshaft .
The props come of easily after 2 years. I used the same recently o other components .
The Granville tin came to hand first although I have some K99 somewhere. .

 

[jointventureII]

I use this:

View attachment 172565

Quicksilver 2-4-C Marine Grease with PTFE 8oz

Seconded

 

[Mr Googler]

Seconded

third…..ed

Never seen it harden up even after a couple of years

 

[Paul1962]

Be sure not to use Copper grease near aluminium

 

[BruceK]

You are are actually looking for a barrier grease if dissimilar metal corrosion is what you dont want then the following lot should be kept in the tool box. Engine, fittings and outdrive

Duralac barrier grease
Molykote 1000
Permatex 77134

 

[Ribtecer]

My outdrive has s/s studs going in to the aluminium with nylock nuts on the studs to hold it all together, so when taking it apart for maintenance it's stainless on stainless. ie no bolts.

Getting those studs out could be a problem, hope I never have to.

 

[kashurst]

You are are actually looking for a barrier grease if dissimilar metal corrosion is what you dont want then the following lot should be kept in the tool box. Engine, fittings and outdrive

Duralac barrier grease
Molykote 1000
Permatex 77134

Thanks for replying. Is Molykote 1000 OK underwater, it has some copper in it?

 

[BruceK]

No. Duralac and some PTFE greases already mentioned above for outdrives. Duralac hardens though. No more lost gearbox covers etc. The other two are more for engine where many are into aluminium fittings. Intakes, water cooled exhaust manifolds and turbo bolts.

 

[BruceK]

Edit. I dont like soft greases in aluminium as it throws out torque settings. I hate stripping ali threads

 

[Mr Googler]

Edit. I dont like soft greases in aluminium as it throws out torque settings. I hate stripping ali threads

Big them big fists of ham you call hands

 

[Momac]

Duralac barrier grease

I thought Duralac looked like good stuff but the safety data sheet says it is very highly toxic.

Maybe the others are similarly not healthy.

 

[BruceK]

I thought Duralac looked like good stuff but the safety data sheet says it is very highly toxic.

Maybe the others are similarly not healthy.

Almost everything you use on a boat is either toxic or harmful. Keep disposable gloves in the toolbox.