How To Check Lube Or Grease Levels In Lower Unit 78 1150

[jeast]

how do i check lower unit grease or lube on a 1978 mercury 1150. and what to put in it if it needs it. is there a online site with all this info? there is a bunch of grease fitting on this engine.... thanks. im asking because mine set about a year before i bought it and when you engage prop forward or back there is a slight grid for a second then all is fine. it is idleing about 1800. i was thinking this could be it as well but not sure how to adjust the idle or what it should be set at...

 

[AMD Rules]

Re: How To Check Lube Or Grease Levels In Lower Unit 78 1150

Although this video is on a slightly newer motor, the process is almost exactly the same: drain it, fill from the bottom till it comes out the vent....make sure to use new gaskets on the drain & vent screws, etc...

http://www.themarinedoctor.com/gearoilmovie.wmv

I use Mercury premium gear lube in mine, but I suppose there would be a few options.

 

[jackyack18]

Re: How To Check Lube Or Grease Levels In Lower Unit 78 1150

I have a question about my mercury 1150 there is a small hole on the outside of the lower unit causing my gear oil to run out, but this isn't an ordinary hole i looked in my manual and it has nothing about it, but the hole does not looked like it was chipped, chunked, or even put there by someone else, this looks like its from the factory! I just don't understand why this hole would be there and cause my gear oil to leak out like its doing. I am going to attach a diagram that shows the exact location of this hole (the hole is about 3/16") very small but looks like it should be there for some reason...If anyone could help and let me know what this hole does before i put JB weld on the thing! Thanks

 

[Yepblaze]

Re: How To Check Lube Or Grease Levels In Lower Unit 78 1150

A 2 stroke motor will exhaust lots of unburnt oily goo into the midsection on it's way out of the motor. Some will collect in this housing.

The hole you describe is to allow water to drain out of that area so as to prevent any water left in that area freezing, expanding, and braking the aluminum housing.

So when the motor is sitting and the oil film and water will drain out that hole.

It's probably not gear oil. Put your finger in it and see if it stinks like gear oil. If it does, you will need to address this by pressure testing the gearcase and looking for the leak.

Otherwise ignore it and move on.

Generally speaking, a 2 stroke in good tune run hard will drain very little goo when parked. A motor run in the driveway or for extended periods at idle will make a mess.

 

[Chris1956]

Re: How To Check Lube Or Grease Levels In Lower Unit 78 1150

jeast, You can use most any marine gear lube in that motor. Do not use Type-C, as it is for electric shift motors (OMC only). Use marine grease from a grease gun on those grease fittings.

If your motor is really idleing at 1800 RPM, you need to lower this, or you will damage your gears. It would really clunk into gear, BTW...