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1959 Johnson 3 hp / cannot separate lower unit

S

Simoniburg

Member
I recently picked up an old outboard and am tearing it down with plans to restore. When attempting to remove the lower unit in order to get to the water pump, etc I find that after removing all bolts it will only separate 3/8". What could possibly be preventing this separation? Any ideas?
 
This must be driveshaft stuck week on History Channel. In this case, I would get some wooden door frame wedges at Lowe's and tap them into the gap until the driveshaft un sticks from the crankshaft. Patience is a virtue here. Do a little tapping, and wait, it will come off. You're getting the 3/8" inch from the drive shaft water pump key bottoming up in the pump housing. Please don't start prying the gearcase with screw drivers to get it loose.
 
If your not in a great rush. Spray some rust blaster so with the motor doing a head stand, it can run down into the splines. Worst case scenario, you tear a hole with the impeller drive pin through the pump impeller housing. Then you can work more in the open. That hole can either be repaired with a little JB Weld, or Marine Tech....or MIG or TIG welded....or dressed smooth on its inside edge so the impeller won't wear on it. The impeller drive hub is beefy enough on these to cover the damaged area, minimizing water escape. These incorporate brilliant engineering where the water pump produces a greater volume with minimal challenge on the impeller arms. With higher volume, lower pressure is required to provide adequate cooling. Impellers in the old days are engineered with stronger arms and thus requiring less arc and providing longer and more reliable life.
 
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My 5.5 Johnson was new in 1953. It has run roughly 2000 hrs....over the last 72 years. It still pumps water like "Ole Faithful". Yes....original impeller....pure rubber, eh? If they can ever engineer an outboard motor with this life expectancy, it will be a cold day in He!!
 
Timguy,
I have several originals that are in the same state, it's amazing how well these engines delivered such brilliant engineering, quality, simplicity and value. Back when society had different expectations of longevity, but you can't grow your manufacturing company making stuff that lasts 75 years! I can't believe the amount of posts on this website where 10 year old 4 stroke engines are nearing obsolescence because of unavailable parts. Welcome to our disposable society. Now off to my 1961 David Bradley 37# gear drive chain saw that needed a carb kit,(still available) to get it running for my yard sale. God I love old stuff!
 
fitz73222 said:
This must be driveshaft stuck week on History Channel. In this case, I would get some wooden door frame wedges at Lowe's and tap them into the gap until the driveshaft un sticks from the crankshaft. Patience is a virtue here. Do a little tapping, and wait, it will come off. You're getting the 3/8" inch from the drive shaft water pump key bottoming up in the pump housing. Please don't start prying the gearcase with screw drivers to get it loose.
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Thank you for the quick reply. I was stumped, to say the least. This is my second rebuild of a vintage motor (1st one was a 1958 Johnson 5,5 hp) so I'm not entirely "green" when it comes to the inner workings of these old babies, but I didn't want to break anything and thus so appreciate your help. Will try the wedge "solution" tomorrow and promise to be patient. Will let you know how it goes. Thank you, again.
 
Agreed---Some of these older OMC motors are a " brilliant " design.----Shift that can not go out of adjustment on the 65 and earlier CD models.----Water pump housing that doubles as a " dowel " to line up the lower unit with powerhead.-----Dual ignition systems.----Very little plastic.------When you take the cowling off everything is reachable for maintenance.
 
Right. A problem with some engineering, did involve the detent which holds transmission into forward or reverse was at the shift lever...fine in the "perfect world"....but when the linkage components wore out downstream of that detent arm, enough movement became allowed, to let shift dog/gears pop out of gear. Many models incorporated detents right inside the transmission itself....so any play upstream was not a critical problem.
 
OKI. Here I am Day 2, with the wooden wedges applied and me walking by every hour or two and applying another tap or two or three on the wedges with a hammer and also spraying "rust buster" inside the lower unit with the intention of loosening the above spline attachment which I am assuming is causing the "failure to separate" problem. I'm trying to be patient while at the same time I'm concerned about the amount of pressure I'm putting on the lower end while trying to separate it. Can "rust" and time really create this much strength to battle me so hard when all I'm trying to do is drop the lower end in order to check out the impeller?
 
timguy said:
Right. A problem with some engineering, did involve the detent which holds transmission into forward or reverse was at the shift lever...fine in the "perfect world"....but when the linkage components wore out downstream of that detent arm, enough movement became allowed, to let shift dog/gears pop out of gear. Many models incorporated detents right inside the transmission itself....so any play upstream was not a critical problem.
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No shifting in this old girl; 1959 3 h.p., 2 piston and no shift linkage. One gear; forward, with a motor mount that allows for 360 degree motion. Want to reverse? Swivel the motor around180 degrees. So why is this beeach giving me such a problem when trying to separate the lower end in order to observe the impeller and water pump?
 
timguy said:
If your not in a great rush. Spray some rust blaster so with the motor doing a head stand, it can run down into the splines. Worst case scenario, you tear a hole with the impeller drive pin through the pump impeller housing. Then you can work more in the open. That hole can either be repaired with a little JB Weld, or Marine Tech....or MIG or TIG welded....or dressed smooth on its inside edge so the impeller won't wear on it. The impeller drive hub is beefy enough on these to cover the damaged area, minimizing water escape. These incorporate brilliant engineering where the water pump produces a greater volume with minimal challenge on the impeller arms. With higher volume, lower pressure is required to provide adequate cooling. Impellers in the old days are engineered with stronger arms and thus requiring less arc and providing longer and more reliable life.
Click to expand...
Still trying to get her separated. Day 2. Lots of rust buster has been deployed along with the wooden wedge/pressure technique that was recommended but she still won't budge. Perhaps tomorrow? If anything, will hammer a few more wedges in and hope for the best. Frustrating, to say the least.
 
Yes it was probably apart before and the repairman didn't anti seize or grease the splines at the top of the driveshaft.
 
Nature locks this together by adding OXYGEN to the steel , one molecule at a time.-----And we know what your 59 model looks like.
 
fitz73222 said:
What is the gap you currently have using the wedges? Has it moved at all. You started with 3/8"
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As of late yesterday afternoon it was still at 3/8." I've dosed it pretty good several times with a rust buster and have pretty intense pressure on it with the wedges. Perhaps it moved a miniscule amount last night? Will see shortly. If not, I will remain patient and just apply more pressure today along with more rust buster. I'll let you know when and if it breaks loose today.
 
timguy said:
Yes it was probably apart before and the repairman didn't anti seize or grease the splines at the top of the driveshaft.
Click to expand...
Good to know. Will definitely be slapping a liberal amount on the top of the driveshaft when I put it back together ... some day, hopefully soon.
 
Yep, she's a cute Lil' Motor that I recently picked up at a garage sale for $35.00. Had been sitting in the corner of a big old barn here in Oregon and was chock full of cob webs, straw and dust. Fortunately, no mice or rat damage although one can tell that it has sat idle for a looong time. (Thus the frozen shaft?) That's why I want to bring her back to life, with a new face lift and essential parts. Plus, like many others here on this site, I truly enjoy working on these Vintage motors although "hiccups" such as stuck lower ends changes that "happy tune" to grumbling curses once in awhile.
 
Look through opening in flywheel.----Look for cracked ignition coils.-----They will be cracked unless they were replaced.----All 1959 coils have cracked.
 
Did you do a compression test? Might be a bad powerhead anyway. Spray some fogging oil in carb and cylinders as a precaution as everything is likely pretty dry. Pull it over with choke on in order to get some lube into crankcase. If no fogging oil is on hand, then use something like WD40. I have some two stroke oil mixed about 8:1 with non oxy fuel in a little squirt bottle. This also works very well as a pre-lube and does not introduce any strange lubricants.


.
 
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Got it! Finally! The wooden wedge/patience procedure worked. Letting the splines soak overnight with alot of pressure from the wedges did the trick when I added more wedges and pressure this morning. In response to your question re compression test, I don't know why I didn't do one other than I just plain spaced it. I know, it's one of the first things I should have done. It's dismantled pretty far and I can see the sides of the pistons (no scarring) as well as the tops,BUT, if the compression was low this would have been a good time to replace rings. Hopefully, new head gasket will help. Thankyou again for your help. VERY MUCH APPRECIATED! Now it's time to see what the impellor looks like.
 
What did the splines look like?, I'm very happy this worked for you. One thing I've learned in this world is a little patience goes a long way to solving problems. :)
 
fitz & timguy, thank you both once again. The splines are ok, but were lacking in grease. It was more like dried tar and only wet from the rust breaker. The impeller looks alright, but at this point I'm going to replace it. I did the "dirty deed" and pulled the shaft and now have to go "all the way" and take a peek at the gears while fighting to re-align the shaft splines with the clutch-dog, etc. I remember doing that with my '58 5.5 hp Johnson and yes! It took patience. ;) (There's that word again). But with this motor lacking a reverse gear I would assume it will be a bit easier? Time will tell. Meanwhile, I hope you two stick close by because I'm 99% sure that I'll be needing your services again before I get this old girl put back together and running again. Until then, enjoy this Summer Sunshine!
 
You too, my friend. Thanks for doing things right. So many motors I get here have been destroyed by lack of ability, knowledge, and yes.... Patience! It's refreshing to know that there are still capable folks out there that can start from the basics and make effective and proper repairs.
 
Here we are a week later after celebrating the 4th! Yahoo! I survived... As for the 3 hp '59 Johnson now I can't remove the gearcase from the lowerend frame as I wanted to replace the 2 bearings (crankshaft & propshaft bearings). After 3 days of frustration I'm about to give up and leave well enpugh alone because there was/is no sign o water in the oil I drained. Any ideas? I have new bearings, but....should I just start putting her back together w/o changing out the 2 bearings?
 
Historically these are very sound units. Can you pressure test it? I use about 5 to 8 psi, with grease drained out. Check with soapy water, both shafts and area where you have been trying to break open. Check shafts for play, side to side.

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I can pressure test the unit in the morning after my Drs. appt. Great idea! If she ain't leaking, I'm going to move on and start putting her back together, including a new paint job. Picked up 2 cans of the custom 1959 Johnson "off white" today. Will let you know tomorrow what the pressure test reveals. Thank you for getting back with me, as always! If I've got "leaky bubbles" I guess we'll cross that bridge then, although hopefully the seals remain intact. Fingers crossed!
 
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