How much Lower Unit Grease?

chry120

Cadet
Joined
Apr 4, 2004
Messages
21
I have a 1977 Chrysler 120hp outboard and I was wondering how much lower unit grease is supposed to go in?? Everything I have seen says to just Fill it up until it comes out of the vent hole. Is this right? Also was wondering when I tested the motor in my driveway with the lower unit in a garbage can with water in it, how much water(at Idle speed) should be coming out of the holes that are half way up the motor? Any help would be great! :D
 

Drowned Rat

Captain
Joined
Jan 20, 2004
Messages
3,070
Re: How much Lower Unit Grease?

Welcome to iboats, chry120. Yes you should fill the lower unit from the bottom drain plug until oil comes out the upper vent plug. Make sure you replace the screw gaskets if they need it. Use a marine grade 80W 90 gear lube. At idle a good spray of water should be coming out the idle relief port you speak of. Make sure when you are running that motor in a garbage can that the level of the water in the can is high enough to cover the water pump. It's not enough to just cover the water intake ports. If the water is not high enough, the pump won't prime. If you don't know the last time the water impeller was replaced, I would replace it, or at the least inspect it. Hope this helps. :)
 

chry120

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Joined
Apr 4, 2004
Messages
21
Re: How much Lower Unit Grease?

Thanks, <br /> Is it difficult to change the impeller? The motor has sat for a very long time, and I think its a minor miracle that I got it running period. I just want to cover all of my bases before I go out and really use it. Is there anything else I need to do before I run it for real? Also, how high does the water need to be to cover the water pump? I had the water up to about 8 inches lower than the water holes that spit out the water.
 

Drowned Rat

Captain
Joined
Jan 20, 2004
Messages
3,070
Re: How much Lower Unit Grease?

chry120, Recommend that you get the manual for this motor. It will explain exactly how to take off the lower unit and replace the impeller. It is very easy to do. A 20 minute job. You should probably decarb the motor. See the FAQ category for instructions on how to do this. Those early model Chryslers are really excellent motors, built very well. Get the manual for it and perform the preventative maintenance. It should last you a long time if you take care of it. :)
 

chry120

Cadet
Joined
Apr 4, 2004
Messages
21
Re: How much Lower Unit Grease?

Thanks, will do!! :D <br />One more question while have your attention.. I didn't get the pin that holds the prop on and I was wondering if I could just use a bolt that was the right size or something like that?
 

Drowned Rat

Captain
Joined
Jan 20, 2004
Messages
3,070
Re: How much Lower Unit Grease?

Yes, you can. Some people use a nail that's the right size and just cut it down to the right length. Coat it in waterproof grease before you install it so it doesn't rust. Good Luck! :)
 

eurolarva

Rear Admiral
Joined
Jun 24, 2003
Messages
4,182
Re: How much Lower Unit Grease?

I would not use a nail or anything else that will fit. I believe that pin is a soft metal that will break if your prop hits something hard. If your prop hits something hard and this pin does not break you run the risk of destroying your motor. Also make sure you put anti sieze compound on the prop splines.
 
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