5.5 Johson '57 lower unit issue

docksider · Jul 4, 2010

I recently used this motor for the first time in a couple of years, then hung it on a rack in the garage. Beneath the lower unit I noticed a bit of lower unit grease and some water on the floor. It seems to be coming NOT from the plug screws used for changing gearcase oil, but from a phillips head screw on the opposite site (from those plug screws) on the skeg area of the lower unit.

Any clues as to cause and fix? Will simply tightening it do the trick? I've done nothing yet.

Thanks in advance.

jimdd810 · Jul 4, 2010

Re: 5.5 Johson '57 lower unit issue

That is the screw that holds the cradle for your clutch dog in place. You could try tightening it but if I am not mistaken those do have a little gasket there and that could be your problem. Now that being said there shouldnt be any water in the lower unit. So i suggest that you check to see if its leaking somewhere else down there as well.

docksider · Jul 4, 2010

Re: 5.5 Johson '57 lower unit issue

Thanks for the reply.

If I need to replace the gasket, what trouble do I get into by removing the screw? Will the thing it secures (clutch dog cradle) wander or stay put until screw is reinserted?

I'm guessing if water can get out from that screw, that it's a likely source of the leak, but that's only guessing.

lindy46 · Jul 4, 2010

Re: 5.5 Johson '57 lower unit issue

It's actually a little o-ring on that Phillips pin. Lay the motor on it's side and carefully remove the pin, and you shouldn't have a problem. When you put it back in, shine a flashlight in the hole to make sure the hole in the shift cradle is still lined up. If not, use an icepick or awl to line it back up, and re-insert the pin.

docksider · Jul 4, 2010

Re: 5.5 Johson '57 lower unit issue

Thanks Lindy. That sounds like something I can do. Perhaps I'll insert a smaller "keeper pin" while I have the phillips pin out of the motor. Here's hoping there's enough of the old O ring to help me match it at the hardware store.

Anything else others think I need to know before starting this, please pass it along.

thanks,
dock

jimdd810 · Jul 4, 2010

Re: 5.5 Johson '57 lower unit issue

Just make sure what ever you put in there to hold the cradle in place dosnt fall in.

docksider · Jul 4, 2010

Re: 5.5 Johson '57 lower unit issue

Good precaution, Jim. Thanks.

lindy46 · Jul 5, 2010

Re: 5.5 Johson '57 lower unit issue

A Johnnyrude dealer will have the proper 0-ring.

docksider · Jul 5, 2010

Re: 5.5 Johson '57 lower unit issue

lindy46 said:
A Johnnyrude dealer will have the proper 0-ring.

probably safer in the long run, but a little out of the way. Our local guy migrated to Merc after the Bombardier days, but he may still have the parts and certainly can get them.

Thanks, Lindy

docksider · Jul 8, 2010

Re: 5.5 Johson '57 lower unit issue

lindy46 said:
A Johnnyrude dealer will have the proper 0-ring.

Following this good suggestion, I learned they don't make/offer it for this motor anymore. Mechanic advised me to a) use close fit from the hardware store or, after noting the need not to let the cradle slip out of position, b) back the screw out, dab the area with silicone sealant, and reset the screw. I'll likely go with the latter option.

I thought this follow up might be of interest as there is still plenty of talk about these older motors here.

dock

wbeaton · Jul 9, 2010

Re: 5.5 Johson '57 lower unit issue

docksider said:
Following this good suggestion, I learned they don't make/offer it for this motor anymore. Mechanic advised me to a) use close fit from the hardware store or, after noting the need not to let the cradle slip out of position, b) back the screw out, dab the area with silicone sealant, and reset the screw. I'll likely go with the latter option.

I thought this follow up might be of interest as there is still plenty of talk about these older motors here.

dock

Don't use silicone. It won't work. Just get one from your local hardware store. However, I doubt that is the source of the water intrusion. I have yet to see an original 1950's OMC that didn't need a lower unit re-seal. Buy a seal kit ($30-40) and fix the problem yourself.

5.5 Johson '57 lower unit issue

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