Best grease to resist salt water washout?

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The product in question is a marine Volvo-Penta DP-S outdrive. This is a dual prop outdrive that has twin coaxial counter-rotating propellers. The forward propeller is notorious for seizing to the propeller shaft when the salt water contaminates the grease in between the propeller hub and the propshaft's splines, crystallizing the grease. It doesn't help that VP uses an aluminum hub and a stainless shaft. Those two metals really don't get along well in salt water. The only solution at that point is to destroy the propeller hub and chisel the remnants of the hub off of the propshaft. Using a puller will only break the puller if the prop is locked to the shaft.

This is an issue with all of the Volvo-Penta dual-prop drives.

I was wondering if there is a particularly resilient grease that will resist salt water contamination to prevent this from happening. The only solution right now is to make sure the props are frequently removed and re-greased.

It's important that the props remain servicable, because the drain for the gearcase is behind the props. If you can't get them off, you can't drain or fill the gear oil.


TIA.
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I've thought of that, but general consensus is that anti-seize won't survive in the salt water any better than the grease.

The problem is exacerbated by the fact that the forward propeller hub is under constant assault by the thru-prop exhaust flow; which is a fairly hot jet stream of both exhaust and salt water used to to cool the engine and exhaust.

Honestly, I don't know what VP was thinking when they made this thing.
 
I can't help with the grease, but I have a tale of the sensitivity of these VP drives. I was in the Coast Guard and we had one in a 24 ft rigid hull inflatable. It topped out at about 30 knots. One day we made a short trip and I could tell the boat was getting slower, and slower. Engine was running normally. By the time we got home it wouldn't go over 18 knots. When we pulled it out of the water we found braided fishing line had wrapped itself around the shaft between the props and spun the hub. Seriously bad design if it can't handle some fishing line...
 
I would suggest Schaeffer's grease #274. That is an aluminum complex grease which is waterproof. The BelRay grease listed above says in the title waterproof but in the description farther down says water resistant. I didn't see what type of grease but probably lithium complex which is only water resistant.

So if you can't find Schaeffer's #274 then at least go with an aluminum complex grease.
 
I'll order a tube of that BelRay and see how it holds up after a 50 hour service interval.

Fishing line is one thing nobody seems to be able to figure out. Outboard or outdrive, if fishing line gets in there, it'll tear out the seal back there. I suppose someone should make a double seal, but there might not be enough room or something.
 
Originally Posted By: SVTCobra
I would suggest Schaeffer's grease #274. That is an aluminum complex grease which is waterproof. The BelRay grease listed above says in the title waterproof but in the description farther down says water resistant. I didn't see what type of grease but probably lithium complex which is only water resistant.

So if you can't find Schaeffer's #274 then at least go with an aluminum complex grease.


#274 on order.
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Originally Posted By: SVTCobra
I would suggest Schaeffer's grease #274. That is an aluminum complex grease which is waterproof. The BelRay grease listed above says in the title waterproof but in the description farther down says water resistant. I didn't see what type of grease but probably lithium complex which is only water resistant.

So if you can't find Schaeffer's #274 then at least go with an aluminum complex grease.


If you dig Schaeffer's, that's fine...but at least spend a minute or two before inaccurately disparaging the Bel-Ray product.

P.S. - Bel-Ray is the manufacturer of Triple Guard grease, which is rebranded under various OEM's.
 
I would also consider something like loctite 680 retaining compound. It will completely exclude water from the joint and will come off quite easily with some heat.
 
Originally Posted By: Diode663
I would also consider something like loctite 680 retaining compound. It will completely exclude water from the joint and will come off quite easily with some heat.


Are you actually recommending a 4000 PSI, anaerobic adhesive to lubricate a propshaft spline?
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Not to lubricate but to exclude water from the joint. With heat it will come off easier then if it was corroded on as he says you have to destroy the property to get it off.
 
Originally Posted By: DoubleWasp
I'll order a tube of that BelRay and see how it holds up after a 50 hour service interval.


I wonder what are the results.
FYI BelRay marine grease is AL complex EP mineral oil grease.
http://www.belray.com/sites/default/file...%20Grease_0.pdf

I don't have experinace with this grease, but I have ben using BelRay waterproof grease - it is non EP ISO170 mineral grease. It is barium+aluminium complex.
 
Last edited:
Originally Posted By: Bluestream
ASK VP, I'm sure they've figured it out by now

Thanks,
BTW I´ve just checked my Belray packed wheel bearing. It seems that they withstand water washout very good.
Yes the additive package is not up to the current standard, but you cannot have everything.

Hopeful I hear other feedback here

Best regards,
Miro
 
Generally Aluminum Complex is not the best option to resist water washout. For most marine applications a Calcium Sulfonate is what is used. Most lubricants companies will have a product with Calcium Sulfonate as a thickener, so take your pick of brand based on that thickener.
 
DoubleWasp,

I don't understand your application needs, but I use this unique grease in fertilizer (salt) injector units with success. Track down the manufacturer and see if it might work for you. It is unlike ANY grease I have ever used...EXTREMELY tacky.

http://www.marinesan.com/Aqua-Shield-Grease-s/239.htm

The tech sheet says its waterproof. But, it is a Lithium base, so that doesn't add up.
 
Originally Posted By: DoubleWasp
The product in question is a marine Volvo-Penta DP-S outdrive. This is a dual prop outdrive that has twin coaxial counter-rotating propellers. The forward propeller is notorious for seizing to the propeller shaft when the salt water contaminates the grease in between the propeller hub and the propshaft's splines, crystallizing the grease. It doesn't help that VP uses an aluminum hub and a stainless shaft. Those two metals really don't get along well in salt water. The only solution at that point is to destroy the propeller hub and chisel the remnants of the hub off of the propshaft. Using a puller will only break the puller if the prop is locked to the shaft.

This is an issue with all of the Volvo-Penta dual-prop drives.

I was wondering if there is a particularly resilient grease that will resist salt water contamination to prevent this from happening. The only solution right now is to make sure the props are frequently removed and re-greased.

It's important that the props remain servicable, because the drain for the gearcase is behind the props. If you can't get them off, you can't drain or fill the gear oil.


TIA.
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yamaha all purpose marine grease. it's salt water resistant, never hardens and stays blue forever.
 
In Europe VP actually sells Propshaft grease. Why not use that? Part no: 3809449. It's a NLGI 4 grease. It's quite heavy and most likely based on calcium sulfonate. I would recoment a heavy calcium based grease if the original product can not be obtained as it works good over here in Denmark. Maybe you have a higher salinity in your water over there. So maybe closer service intervals will be a proper measure.
Best of luck.
That said a Z-drive needs alot of intensive attention to last. It's a quite complicated assembly exposed to the elements. Only protected by simple bellows and seals. If any of these fail you have a healthy invoice on your neck in no time. So give your drive the attention it needs. And the calciumsulfonate grease to stay happy.

Motorsen
 
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