Gear lube and gasket material

[CaneCutter79]

I will be changing my lower unit oil this weekend. My manual is old and references OMC "Hi Vis" lube. I doubt they make this still.

I see there are ranges of lube on weights. What are advantages of one weight over another? Also, its not recommended to use synthetic for lower unit oil right?

Only need 1qt right?

Also, I'm replacing the bearing assembly o-ring. The manual instructs me to apply gasket material to the big o-ring and the 4 bolt oil-rings. Is it RVT or a specific marine gasket material?

As usual......thanks to all who answer questions at iboats! Best marine forum out there!

 

[HighTrim]

Re: Gear lube and gasket material

Im not sure which motor specifically you are referring to, but 90 wt gear oil for marine use, or hypoid gear oil is fine. Im not sure why you would not want synthetic?

Amount depends on motor.

 

[CaneCutter79]

Re: Gear lube and gasket material

My motor model number is in my signature. I read somewhere on this forum and someone said to not use synthetic in the lower unit.

What about the gasket material for o-rings?

 

[boobie]

Re: Gear lube and gasket material

Are you talking about the prop shaft brg carrier ??

 

[CaneCutter79]

Re: Gear lube and gasket material

Are you talking about the prop shaft brg carrier ??

Yes.

 

[F_R]

Re: Gear lube and gasket material

They are talking about OMC/BRP Gasket Sealant. Similar to Perfect Seal #4 (Is that still available?). I'm sure you will try some substitute. But RTV it ain't.

 

[boobie]

Re: Gear lube and gasket material

Don't use the rtv. Use the OMC Gasket Sealing Compond or Permatex # 3. Be sure to coat the rest of the outer hsg with it and make sure the g/c hsg is good and clean where it mounts.

 

[CaneCutter79]

Re: Gear lube and gasket material

Don't use the rtv. Use the OMC Gasket Sealing Compond or Permatex # 3. Be sure to coat the rest of the outer hsg with it and make sure the g/c hsg is good and clean where it mounts.

Yep, I plan on degreasing the area around the shaft before putting the housing back in. It's coated with sludge and oil. I can get Permatex #3 at O'Reilys or Walmart and such right? I don't know of a local place where I can get any OMC compound. Unless Academy or Cabelas might have it.

 

[boobie]

Re: Gear lube and gasket material

Your local BRP dealer should have it. Just get a can of something that has a brusch in it, not a tube,

 

[WIMUSKY]

Re: Gear lube and gasket material

My motor model number is in my signature. I read somewhere on this forum and someone said to not use synthetic in the lower unit.

I use Johnnyrude HPF XR synthetic blend in my gearcase..........

 

[CaneCutter79]

Re: Gear lube and gasket material

I got lucky and was able to find OMC gasket compound (brush in can type) at a local marine shop as well as OMC Hi Vis lube. Looked hi and low for a lube pump and finally found one at Walmart.

Ready to go now. Thanks again for everyone's help!

 

[CaneCutter79]

Re: Gear lube and gasket material

Do I need to let the gasket compound dry for a period of time before putting the boat into the water?

gotten warm or something to turn it into into a thicker consistency?

I am going to degrease the assembly and reinstall with new gasket and then put in need gear lube. is there a message for removing any excess bad lube before adding the new lube?

 

[CaneCutter79]

Re: Gear lube and gasket material

Method***

Not message....

 

[boobie]

Re: Gear lube and gasket material

Put it all together and put it in the water. Done it many times.

 

[CaneCutter79]

Re: Gear lube and gasket material

So I put it together, ran the motor about 1hr yesterday with numerous short runs while fishing a small lake. Pulled the boat out , no oil leaking out.

Checked the lube when I got home and it has a slight creme color to it. Not white.....just not clear like melted carmel color that it was out of the bottle.

Could water have gotten in? I will check again tonight. I'm hoping the lube mixed with some of the old black lube that didn't drain out and has air entrainment in the lube. Hoping it will settle and turn a clearer color. If the water and lube separates, water goes to the top right? I should be able to insert a zip tie in the top to check for water right?

 

[CaneCutter79]

Re: Gear lube and gasket material

Here is a photo of the lube. After looking at it closer and in better light, you can see the oil mixed with any residual oil that remained in the gearcase. The oil changed from a light brown honey color/transparency to a somewhat green and brown mix with a slightly darker tone. Signs of being mixed with the older oil that was very black and a dark green color.

I think I'm good and without water. I used a plastic zip tie as my "dipstick" and I didn't have to put the tie in very far before pulling out oil with no water. If it had water, the water would have separated and float on top of the oil. Also, if it had water the oil would look milky and whiter than this.

I have two images below. One with a flashlight on the oil and one without the flashlight. You can see two different colors from these photos. It's probably closer to the lighter color with the flashlight on the oil.

 

[WIMUSKY]

Re: Gear lube and gasket material

Water wont seperate from the lube unless you have a tremendous amount of water in the gearcase. Looking at the pix, I would change it again.

 

[CaneCutter79]

Re: Gear lube and gasket material

Why change it again? The old oil didn't drain completely out. I drained out all that I could. It drained overnight but after moving the boat into my garage, more slowly trickled out (just a little).

I think the old oil mixed with the new oil.

 

[CaneCutter79]

Re: Gear lube and gasket material

I performed some experiments and mixed new oil with old oil, new oil and a few drops of water, new oil with old oil and drops of water and finally compared them to the oil from the lower unit.

The result was any oil that has water will loose its transparency when spread thin.

Thus........I have water in the oil. (Crud......there went $20 worth of Hi Vis)

So I replaced the o-ring and all of the o-rings for the 4 bolts but for some reason I didn't replace the prop shaft seal. I suspect tat is where the water got in. The old o-ring was flat sided and needed replaced. It was drying too. The new seal was coated with gasket compound. So much it was almost dripping so I doubt the new seal is bad. Must be the prop seal.

I'll order a new o-ring and prop seal and do it all again.

Does this sound normal? It shouldn't leak after replacing prop seal. Prop seal looked OK to me but must have a slight fraction of an inch that is letting in some water.

Stupid question.....
The water in the lube can create rust over a long time period if not replaced? Is that why you don't want water in the lube? Also reduces viscosity as well correct?

 

[jim j geezer]

Re: Gear lube and gasket material

First, if you have any significant amount of water mixed in with your lower unit lube: The oil will float ON TOP of the water. Meaning that when you drain it, water will exit first. It also means that your cheap trick for inserting a wire tie COULD give you a false indication. Even poking the wire tie all the way to the bottom (where the water might be), it'll be wiped clean of any water by the thicker lube that'll just act as a squeegee.

Second, just a couple of drops of water in your lower unit is HIGHLY UNLIKELY to do any damage.