Johnson A-50 won't turn all the way over

[asdasc]

I got a little bored today and drug out an old A-50 to take a look at. At first it wouldn't turn over at all, but after soaking the cylinders with Deep Creap and rocking back and forth on the flywheel nut it came free. The problem is that it won't go all the way around. I can spin it about 350 degrees and then back around 350 degrees in the other direction.

Is there anything that I need to know about these motors that might cause this?

I have no history on the motor, it came with 3 others that I bought on craigslist. On the plus side, it looks complete other than the fuel glass.

 

[1946Zephyr]

Re: Johnson A-50 won't turn all the way over

Oh cool. An A-50, huh? I love those old motors. I say just flush the hell out of those cylinder walls with WD-40 and get all the crap out, that caused them to get stuck in the first place. It sounds like you're making good progress and got it to move, which is good. If you just keep working at it, then you'll do okay. Worst case scenario, you may have to pull the cylinder jugs and clean them out and hone the cylinders. That would be a good opportune time to check the pistons and make sure they are good to be put back in service.

 

[james williams]

Re: Johnson A-50 won't turn all the way over

maybe the foot is locked? is it out of gear?

 

[1946Zephyr]

Re: Johnson A-50 won't turn all the way over

there is no gear, it's a direct drive. This motor is 1930 and the first Johnson alternate firing twin. I had one like it once

Checking the lower end would be another good place to start though.

 

[Chinewalker]

Re: Johnson A-50 won't turn all the way over

Great little motor! I've got an A-65 in my stable and enjoy running it! Very smooth for a 1930s motor.

I concur with the above - Flush the heck out of the powerhead. I think I might consider pulling it down if it had that much in it - at least partially as you don't want that stuff to chew up the bronze bearings. Also check the lower unit. Might be a bit of crud or even a broken gear tooth preventing full spin.
- Scott

 

[asdasc]

Re: Johnson A-50 won't turn all the way over

Thanks guys. I will try to pull the lower unit and see if that frees is up. It would make better sense to me if it was stuck at the top of one of the cycles, but where it blocks is when both pistons are out of view thru the plug holes. I have been very hesitant to tear it apart because I didn't know if seals and gaskets were available.

I will check into that. I take it the bearings in the powerhead are bronze? No roller bearings here, eh?

My plan was to 'just get it running', not do a full restoration. Mostly because I subscribe to the 'if it ain't broke, don't fix it' theory based on my past history of finishing projects. I do have 5 old outboards to a point where I think they will run once the water thaws, however. Non-running motors started following me home once I got an old cottage on an island 2 years ago.

 

[asdasc]

Re: Johnson A-50 won't turn all the way over

Also, when I went to pull the flywheel, I found the bolt threads weren't in my supply of hardened bolts. I thought I had them all!

It seems to be 1/4 - 22. Can someone confirm that? I want to run out and buy some this morning if I can.

 

[asdasc]

Re: Johnson A-50 won't turn all the way over

OK, I have identified the bolts I need. It looks like it is 1/4-24, which is not a standard size. Any idea where I can get 3 hardened ones?

 

[1946Zephyr]

Re: Johnson A-50 won't turn all the way over

A cottage on an island? Awesome!

The gaskets on those are easy to replicate from gasket material. I've had to make several in the past, myself. with that A-50, you may only need to make the cylinder gasket. Your local auto parts store sells gasket material that would work good for that. Just trace your old gasket on the new and cut it out with an exacto knife.

 

[asdasc]

Re: Johnson A-50 won't turn all the way over

Thanks, I can make gaskets easy enough if there are no special materials needed.

The cottage has been a labor of love. It was almost in tear down condition when we got it. I am doing all the work myself with friends and family on weekends. We have already put on the new roof, built a lookout, gutted it, installed plumbing and electrical 100%, and am not replacing windows and doing siding as time and funds allow. Now is a good time to get things over there since we can walk across the ice!

 

[asdasc]

Re: Johnson A-50 won't turn all the way over

GOOD NEWS!!

After going away for a week long business trip, I came home and tried to pull it. It now spins all the way around!!

It is still a little tight in one spot, but it seems to be getting better. I can't find a good way to spray deep creep down into the crank directly. I have been spraying it into the plug holes with the motor tilted way back horizontal while spinning it over by hand. The stuff runs somewhere, and I think it is the crankcase because when I tilted it up, it all came running out the exhaust down at the bottom.

I also pulled some smaller parts and started cleaning them up. There is a very wierd valve about halfway down the leg on the side. Any idea what it does? I will post a picture later.

 

[asdasc]

Re: Johnson A-50 won't turn all the way over

As an update on this, after letting it soak for a few weeks, I got to working on it again last night. I decided to pull the lower unit just for kicks and was shocked to find the power head is as smooth as silk!! The lower unit was binding. (I know, I am an idiot!)

Anyway, after pulling apart the lower unit, it was all in pretty decent shape except it was stored without fluid in it. There is one spot on the drive gear that started to rust kinda badly. Ideally, I would want to replace it but I think if I adjust the lash properly it may just work.

If anyone has a spare available, or a source, I would be interested.

 

[CATransplant]

Re: Johnson A-50 won't turn all the way over

I think that's toast, frankly. Go ask the folks over at www.aomci.org. You could probably score a new shaft and gear on their free classified section for a reasonable amount. Buncha good guys over there.

 

[asdasc]

Re: Johnson A-50 won't turn all the way over

My dad is a member of AOMCI and they had a local meet over the weekend. I was able to pick up a better lower unit for $25 locally, and I will be putting it on this week sometime.

I need to also pull the flywheel and replace the condensors and the plug wires. The coils and points test out good. I hope to have this one running soon. Thanks for all the help!