1974 15hp johnson gear lube leak

[Seriousbert45]

I have a 1974 johnson 15hp seahorse and its leaking what im pretty sure is gear lube out from a small hole in the front. Im not sure if this is a difficult fix or what I would need to do.

I attached a picture with an arrow pointing to where the leak is coming.

What exactly is that hole in the lower unit called?

Does anyone know what this could possiblily be or how I could fix it?

Any info would be fantastic thank you!

 

[HighTrim]

Re: 1974 15hp johnson gear lube leak

I myself do not have one, but i believe that is a drainage hole. Are you sure that you're leaking LU oil? What does it look like? When you drain you LU lube, is it low, milky, white?

 

[F_R]

Re: 1974 15hp johnson gear lube leak

Chances are it is not gear lube. That is a drain hole for water and any other crud that may be trapped in a cavity inside. Gear oil would be leaking out the water intake screen or around the prop shaft.

But check your gearcase for being full and no water in it. And recheck it after a few outings to be sure.

 

[reload]

Re: 1974 15hp johnson gear lube leak

May be the shaft seal is leaking and some how getting to drain there.

 

[Seriousbert45]

Re: 1974 15hp johnson gear lube leak

Thank you soooo much for your help you guys. I really dont know much about boat motors and I just bought this one that I am using for a boat that im building which will be done hopefully soon. So.... I havent really gotten a chance to have it running since I got it. I also have not gotten a chance to change the gear lube so far.

As soon as I do change the gear lube I will let you know what the scoop is on it. But I talked to a guy I know who knows a bit more about boat motors then myself. He was unsure what the hole was for on the motor but he thought the oil was gear lube.

The guy I bought the motor from had not had it running in about 2 years or so because he did not have a boat to put it on. It fired up and ran really well when I got it. No problems shifting or anything and he said it didnt have any problems with it. He did say that he mixed the oil a little rich because it had not been run for a long time so he didnt burn it up at all or anything.

I'm really no oil expert so thats part of the reason I had the other guy come out and take a look at the oil coming out of that hole. It was just a very very slow leak outta the hole maybe like 4 to 5 drips a day and that was about it for about 2 weeks.

Thanks again for all your help! I'll keep you posted with any more info I find on it.

 

[Seriousbert45]

Re: 1974 15hp johnson gear lube leak

Alrighty, so... I changed the gear case lube and I think im gonna fire her up with a set of muffs tommorow and run some seafoam through the gas to clean the carborator out a bit.

When I did change the lube it was really black with a few brownish streaks through it. It was a little low but I dont believe it had been done for quite awhile now.

I have not seen anything leaking out that drainage hole since I changed the lube but who knows after I run it for a few minutes that might change.

Any suggestions before I fire her up?