Conventional 2050 in alpha 1 drive

[leroyd92]

We have taken the little boat out a few times now and after checking the drive oil, the upper half of the drain came out black. I hand no prior history of how long that fill was in there but when I restored the boat I changed at fluids.

I know 2050 is like 7590, but would it be safe to run in the drive? I know boats go under more abuse. So I'm open minded a in running something thicker if convinced

 

[Ramblejam]

20w-50 is not like 75w-90. One doesn't replace the other.

Listen to me very carefully.

DO NOT, I repeat, DO NOT put 20w-50 in that drive.

Marine gear lube is commonly tested to maintain acceptable performance under 10% water contamination. Mercury High Performance, Amsoil Marine, or Royal Purple HPM come to mind as good products.

 

[leroyd92]

so, harley davidson uses syn 2050 in trannies, but it cant replace 8090?

 

[leroyd92]

im open to use some of the 5 gallons of non marine 8090 at home...

 

[Ramblejam]

Your example is a poor one, especially given that there's all sorts of information out there regarding the superior performance of a proper gear oil (that's formulated for the application) in those Harley transmissions.

Look though...do whatever you want. 20w-50, non-marine 80w-90, or grape jelly. I'm not losing any sleep over it.

 

[leroyd92]

So in general, in a perfect world, if I don't have any water introduced into my drive, wild standard 8090 be fine for the drive?

The other reason why I thought 2050 could be used is the motor is only a 3l 140hp motor.

 

[DoubleWasp]

I wouldn't play around too much on a gearbox that has 75-100 hour OCI'S. That's pretty low by engine standards. By gearbox standards, that's not even a blink of the eye. Mercruiser High Performance Gear Lube is not so expensive that I'd pass it up for what? A 3 quart fill?

Do whatever you want, but you asked the question, so there is the answer.

Who cares what HD uses to smack around an 800 lb. bike?

 

[Donald]

You need 2 QTs of marine gear oil. Walmart sells Mercruiser (which is excellent). Also 2 new gaskets for the drain plugs and a pump. You fill from the bottom one with the pump until it comes out the top hole. The pump must have threads to screw into the drain plug hole.

The drive is about $1500 (at least) and the gear oil and pump are under $20 total.

You will not know when water gets in and starts to cause havoc. Even if the drive is 100% sealed when you start boating, you could catch fishing line around the prop and damage that seal at any time.

The way to test the drive is to put air pressure in it, and see if it looses any pressure. Some also do a vacuum test. Both should be done with no gear oil in the system.

 

[leroyd92]

Looks like I'll be sticking to gear oil.

I'm only familiar with the 85 Volvo 290 system which takes (same as engine)

So knowing this, I didn't really take marine gear oil seriously

 

[leroyd92]

And it still kinda send strange how mercrusier specs 8090 and our Volvo "if I go by the manual" specs 1040. Which I would be scared to use

 

[Donald]

Originally Posted By: leroyd92
And it still kinda send strange how mercrusier specs 8090 and our Volvo "if I go by the manual" specs 1040. Which I would be scared to use


Evinrude back in the 1970s used an odd gear oil in their electric shift outboards. But all the rest of the outboards and outdrives seem to use marine gear oil.

 

[Chris142]

If its got hypoid gears like a differential it needs a gear oil.if it has straight cut gears like a motorcycle then 20w50 will work. But add in water and it needs a boat oil

 

[leroyd92]

Originally Posted By: Chris142
If its got hypoid gears like a differential it needs a gear oil.if it has straight cut gears like a motorcycle then 20w50 will work. But add in water and it needs a boat oil


That's the clarification I needed.

I'll just use gear oil.

 

[wca_tim]

This is the answer.... trust me. from a guy that has built and/or replaced more than a few out drives after blowing them up... (mine and thos of friends) The largest culprit by far is water intrusion... Redline shockproof (and some other gear lubes) does a great job holding gears together in an overpowered drive... until you get a very small amount of water in it, then it doesn't work anywhere nearly as well as the mercury green stuff... I wouldn't use anything else... outdrives are way expensive compared to a couple quarts of expensive mercury synthetic hypoid gear oil...

hopefully you're convinced now... otherwise, run outdrives long enough and you WILL have a leak, and it will come apart... IMHO.

Good luck!

Originally Posted By: Ramblejam
20w-50 is not like 75w-90. One doesn't replace the other.

Listen to me very carefully.

DO NOT, I repeat, DO NOT put 20w-50 in that drive.

Marine gear lube is commonly tested to maintain acceptable performance under 10% water contamination. Mercury High Performance, Amsoil Marine, or Royal Purple HPM come to mind as good products.

 

[ragtoplvr]

You do not know the pressure load on the gears. A lightly loaded gear does not need to oil a heavily loaded strong alloy gear needs.

Rod

 

[DoubleWasp]

First time I saw an outdrive broken down, I was impressed at how tiny some of those gears are. They must be under some ridiculous stress.

 

[leroyd92]

well im shamefully reporting that the outdrive oul was a bit low and really dirty...

when i got the boat in mid 2013, it had sat 4 years...

engine needed a diesel flush to unstick all the valves, ( sounded like a diesel ) and i drained the drive ( really dirty)

i see no signs of water intrusion but im going to frequently check the drive from now on and see if it gets low...