Lower Unit Lubricant
 

1980 200HP Merc. Black Max.

The lubricant is creamy in color, which I think is an indication of water seepage. Reading the repair manual, trouble shooting the problem is beyond my skills. Although the rest of the motor has been rebuilt, the lower unit is original and the only work done to it has been the replacement of the water pump and/or impeller various times, oil changes (lubricant) and replacement of the vent screw and seal washer. Is this something I need to address or not a big deal and just replace the lubricant monthly? Any suggestions on the repair? As always, your expertise is welcome and greatly appreciated. Thanks! ???

Re: Lower Unit Lubricant
 

Creamy color is water! You need to fix asap!

Now you say that the lower unit oil has been changed, when was the last time? Did you or they replace the washers on the fill & drain screws when you did it?

I would drain all oil, replace screw washers, and refill.

If you get more water then you have a seal gone and it will need further work.

They can persure test the unit to see were it is leaking, but that might be best left to a pro?

Start with the screw washers and oil change.

Good Luck

Re: Lower Unit Lubricant
 

Only replaced the vent screw and washer - will go ahead and replace the fill screw and washer. Thanks.

Re: Lower Unit Lubricant
 

You will need to drain the oil and change the washers on both!!
This should be done everytime and on both!!

Good Luck!

Re: Lower Unit Lubricant
 

The past 2 units I've changed the fluid in looked milky, both ended up being the seals under the water pump. Many people don't change out the water pump base, which leads to water intrusion down the road.

Re: Lower Unit Lubricant
 

milky coloured oil can also be directly associated with excessive beer consumption while wrenching on your boat and is a warning sign that you might need the 12 step program to recovery :-[ ;D ;D

Re: Lower Unit Lubricant
 

THEFERMANATOR, That's a god one - never changed the water pump base or the seal.

Hangbelly, Don't tell me that .... I just finished with step 12 last month, my fourth time. ;D

Re: Lower Unit Lubricant
 

Builder...how's yer dash lookin' these days ??? ...

Re: Lower Unit Lubricant
 

Hi Builder,

There is a product called "Seallube" which when added to LU oil swells the seals stopping the water intrusion into the LU. If the seals are really bad, Seallube may not work, but it's worth a try. Also, full synthetic lower unit oil can take alot more water than standard 90 hypoid LU oil before breaking down. My Yamaha 150 LU takes about 1.5 quarts of oil and I add 2 oz of Seal Lube to it when I change it. I bought the Seallube on Ebay. One of the V20 gurus (I forget which one) swears by Seallube. !

Geek

Re: Lower Unit Lubricant
 

BuilderFl:

I have a lower unit pressure tester I can ship to you to aid in trouble shooting (as long as you send it back when your done - No Hammer I'm not giving it away :-).

t is often easier to ID where the leak is after pressuring the case. Let me know if your interested.

Kamikaze