View Full Version : Drive Unit Oil?

11-21-2005, 03:47 PM
Will my engine use up the Drive Unit Oil so that I need to refill it? Or could I have a leak or maybe some other problem?
My engine is brand new and I am not familiar with how the Drive Unit uses oil. Luckily my boat was equppied with an alarm that kept beeping very loudly or I could have been in big trouble this morning. Thanks for any help I can get. My owner's manual doesn't explain anything and the dealer I bought the boat from never did either.


11-21-2005, 03:56 PM
The lower units on outboards and stern drives don't consume oil. Lube can leak out or more typically mix with water that leaks in. I'm not familiar with jet drives if that is the drive unit you are referring to.

Maybe oil was never added to the unit at the factory or at the dealer.

11-21-2005, 04:04 PM
It is an I/O and there was fluid in it, I saw that it was full and never messed with it. Now it has definitely used some up and emptied almost all of the reserve. As far as it being a leak, I don't have any oil inside my motor compartment and I have never seen any kind of discharge on the water. Maybe I should take it to a mechanic? Thanks,


11-21-2005, 04:10 PM
Is "new" brand new or have you had it in for any warranty service or 20 hour service yet? On the bright side, whatever it is should be covered under your warranty.

11-21-2005, 04:28 PM
I must admit I am a little past due on maintenance. But I have the extended warranty so I am not to worried about it being a major problem. Just not sure if it was normal for it to use that oil? Logic tells me that it should be there or have leaked out somehow ??? It's not the motor oil where it could have burned up, which is all there at the proper level. The dealer never explained to me about a 20hr service and I have only changed the oil myself 1 time. I have not been running it at high speeds but 95% of the time only trolling. I think I had better take it to the dealership to make sure my warranty is still valid. Can they exclude me becuase I didn't take it to a authorized rep?

11-21-2005, 06:57 PM
"I am a little past due on maintenance"

How long is a Little past due?

The reason I ask is that although you do have a warranty, you as the owner have obligations that you must keep to have the warranty be honored.

Regular scheduled maintenance (Or lack of that is) is one of those picky little things that will allow the manufacturer or dealer to look you square in the eye and tell you although they are sorry and feel your pain since you didn't keep up the "Owners periodic maintenance" end of the bargan your warranty is null and void.

This is where you really need to read and understand the fine print on these things.

As stated your lower unit will not "Use oil" unless there is a problem, the oil you refer to is a 90 weight gear oil that is specifically designed to be used in gear boxes.

You may in fact have a leak.

First sit down and read your owners manual about how to use and care for your motor, find the spcifications part and see how much gear oil this unit takes. You should have done this first before you ever put the boat in the water

Now if you want to follow the directions and change the oil, it's only 2 screws and remember to tilt the motor to get it to drain properly, then lower the motor and refill from the bottom hole. If the oil is milky whitish you have a problem and should go to the dealer, take the oil with you.

Just remember righty tighty...Lefty loosey.

My advise though is to take the rig back to the dealer for its first servicing, this is assuming you have the breakin hours completed.

Make sure you specify what you want done, ie, the breakin servicing, they should do all the oil changes and also check all the settings, if you noticed any problems with the boat or motor this is the time to bring them up.

Do you have a fuel water seperating filter on the boat?

If not get one installed when you take it in. Get the Raycor ten micron filter cartrige for it as well.

They are mixing ethanol with the gasoline now and it will screw up your engine if you don't.

There are things you need to do if you are not going to use the boat all winter, as in winterizing the boat and motor, do them!

If your boat is going to just sit all winter add the correct ammount of fuel stabilizer (I use Stabul which I get at Kragens) to your tank and fill the tank completely to get rid of any air pockets which cuts down on the acumilation of water in the tank from condensation.

Ask your dealer about winterizing as they can do it too.

If you don't put your boat to bed properly for the winter it will be a serious problem come spring and
A. Won't run for beans.
B. Will cost you big bucks to fix.

11-21-2005, 08:06 PM
Thanks Jan,

After reading my owners manual more carefully it says that the first oil change (servicing) should be done after 100hrs not 20hrs. Although there is a 20hr break in period the fluids are not required to be changed until 100hrs. The Motor Oil has been changed at about 40hrs and I am at around 120hrs. I found out that there can be air pockets that will settle and allow the *drive oil to fill the space, this seems to be fairly common and I am hoping that is all that's wrong.
There is no water in any of my other oil or in what was left in the reserve for the drive oil.

Thanks again for your reminders of the resposibility of boat ownership and importance of proper maintenance.


11-22-2005, 10:40 PM
What brand and model is your engine and drive unit? It sounds like you have a mercruiser from the way you refer to a reserve resevoir. Are you sure the recomended service interval is 100 hrs. and not 50 for the oil change. I know the manual says you can go longer than 20 hrs. on changes but are you sure it doesn't have a section that covers break in proceedure. That is where it should give additional info for the first service. I'm not familiar with all makes and models but 100 hrs seems long.

You are correct that air bubbles can cause some settling of the fluid but they usually work their way out quickly. 15min or so is normal. At the very least they would be gone the first time you used the boat. You get less air bubbles if you fill from the bottom but still check again before use.

Many dealers include the 20 hr service with the purchase of the boat. Yours may have as well and you may not have known it. Either way if it looses oil in the future or the oil starts changing color at al take it in.

One possible way you could loose oil is if fishing line got wraped around your prop shaft and damaged the seal. It's fairly common for this to happen and can cause some real expensive damage that's not usually covered by the warranty. Before you take it in you may want to take the prop off and check for line. If they see it they won't cover it.

Good luck and protect that extended warranty. Read the fine print.

11-23-2005, 04:19 PM
Thanks fish-n-again,

I do stand corrected again, it does recommend to change the motor oil after 20hrs. Anyhow I am having it looked at and will have to bite the bullet if have been negligent beyond what is allowed. I was more concerned with fishing than maintenance ??? Stupid Salmon Fever ;)

Hi my name's Ken and I have a problem!

11-23-2005, 05:49 PM
Good Luck Ken, & OBTW have a good Turkey Day.

11-23-2005, 07:05 PM
Sounds like the wise thing to do. After all you have a lot of cash tied up in that boat. I've had several warranty issues with my boat. One being water in the outdrive oil. The dealer was looking for any excuse to say HA HA NO WARRANTY FOR YOU. I did my research and they had to do the work under warranty after all. It was a seal that I could not have possibly screwed up myself.
Now hopefully the dealer gets your boat back to you quickly. The dealer always seems to have my boat 2-3 times longer than they say at first. Six weeks one time. It sucks to loose that much valuable fishing time.

Good luck ken. See you out on the water sometime.


11-23-2005, 07:12 PM
OH by the way I have an 5.0 mpi mercuiser I/O. Good call on the type by the description of the reserve tank. Yours must be similar or you know about engines.

Thanks for all the help guys, I appreciate evry bit of it.

Have a great Thanksgiving and Good Luck out on the water.


11-25-2005, 09:18 AM
I change my outdrive oil at the beginning of every boating season but this year it blew a seal out while we were couple miles from marina. Made it back and drained outdrive full of water I pulled out drive and took to be repaired still waiting for it (750.00) you have to check on a routine maintance list. :-[

11-28-2005, 03:35 PM

It was only an air bubble 8)
Just got the word back from the mechanic. He did a pressure test and there was no leak. It was just a case of outdrive indigestion ;D

Thanks again for all the advice.
Looks Like I can get back to business!

Fish On!


11-29-2005, 09:54 AM
That is good news. At least your dealership remembered to put oil in it in the first place. The dealer my friend bought his Striper from forgot to put any in. Oh yeah they also forgot the power steering fluid and trim fluid as well. OOOPPPSS. My dealership also forgot the power steering fluid. The moral of the story is check your fluids and check them often. Don't assume the dealer did anything right. I check my fluid levels almost every trip. At the very least you'll spot trouble early.

Glad to hear the good news. Now go catch some fish.