Today on the river I was going full speed when all of the sudden the motor slipped out of gear. I stopped and then tried to get it back in gear (forward and backward) and it would not engage. Took the cover off and it looks like the shifter cables are doing there job, it just won’t go into gear. Any ideas of what could have happened? It is a 93 or 94 50 HP Johnson.
Any help is greatly appreciated.
Thanks.
Have you checked your prop? You may have “spun” the hub, so that the splined coupling is loose within the rubber bushing.
HRG
I quick took the prop off and didn’t notice anything like that. The nut behind the pin was a little loose, but that’s not what you are talking about, correct? I then took off the rubber bushing and looked at the metal shaft (not sure what real part names are) that spins the propeller & everything seemed okay.
Put a mark on the shaft and your prop and see if they stay lined up after you run it.
Try this, put the prop back on, with the nut and cotter pin. Hold the nut with a wrench or pliers, so it can’t turn, and see if you can spin the prop. If the prop spins, without the shaft rotating, the hub is bad.
If the prop checks out OK, I think there is a cross-pin that retains the gear at the bottom of the driveshaft, it may have failed. Depending on your skills, you’ll probably need to get the lower unit pulled and repaired. Standing next to the motor, when it is shifted in and out of gear, does it appear as though the linkages and gears are moving?
HRG
Thanks for the input, I’ll try these recommendations tonight when I get home.
Thanks again.
My guess is you lunched the lower unit.
-J.
You may also want to drain the lower unit oil and see if there are any metal filings in it. If it isn’t the prop, you’re probably looking at a lower unit rebuild.
Ughh….I hope that’s not the case. What the cost on a lower unit rebuild?
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Ughh….I hope that’s not the case. What the cost on a lower unit rebuild?
Probably in the $600 range if you are not in a hurry to get it back. More for a rush job. It not the parts so much as the labor. Takes some time to get that job done. You may want to check with the bone yard too:
http://www.twincityoutboard.com/
-J.
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My guess is you lunched the lower unit.
-J.
Agreed.
So I’m guessing if I put in gear and prop spins freely that is bad news, correct? I’ll try when I get home, all I know is that if it’s the lower unit, my fishing time will be greatly reduced for the rest of the year. 
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So I’m guessing if I put in gear and prop spins freely that is bad news, correct?
Correct.
Also do as suggested and drain the lower unit and feel around in the oil for metal shavings or chunks…. When those gears let loose, they make a mess inside there. 
Let us know how it turns out. Hope I’m wrong here!!! But had the same motor and lunched the LU just as you describe.
-J.
I wasn’t able to run through everything mentioned above yet, but I did put it in gear and the prop does not spin in either forward or reverse. I sure hope that means it’s not the lower unit. I’ll try the other suggestions this weekend. Thanks for all the input guys!
So the prop does not turn if in gear and I drained the lower unit and there was a little bit of metal shavings, but really not all that much. Are we still thinking lower unit rebuild? I would think there would be more metal if the entire lower unit ground up into pieces.
Sounds more like a cable adjustment is needed. Or your shifter dog is crapped.
Im with you herb. I’ve done my fair share of lower units on my own motors and a couple for friends. The first thing Id do is check and see if the linkage is worn and needs adjusting after you take the motor cover off. The linkage is that little lever and threaded rod setting just under the powerhead and is connected to the shift cable. Make sure there isn’t any slack and the lever is swinging a full stroke back and forth. Wear will make it swing a shorter stroke so the clutch dog in the lower unit can’t do its job.
This is basically what it is; the clutch dog is in the lower unit and it slides back and forth on the prop shaft and it does this by a U lever that also rides the clutch dog and is activated by a rod that comes down through the center cowling from a lever by the shifting cable. On the clutch dog theres two raised ridges, one on the back of it and one on the front of the clutch dog. Both of these ridges ingauge with eigther the forward gear or the reverse gear depending one which end of the shaft thier on.
Take the prop off then look at the cover plate where the prop shaft comes through. On the cover plate theere may be two holes for a spanner wrench or a grove for another kind of spanner wrench. One fits into the holes, the other fits into the grove of the cover plate. The reason I say this is because I don’t know what your cover plate looks like.
After inserting the wrench turn couter clockwise and take the cover plate out, you will then see the reverse or forward gear.
Theres a cover on the side of the center cowling and thats where you take the coupler off that holds the two shift connecting rods together, you have to disconnect these two rods so you can drop the lower unit. After you’ve done this take the bolts out that hold the lower unit to the center cowling and pull the lower unit down and out of the center cowling. You might have to use a screwdriver to pull apart that clip that holds the two shifting rods together under that cover plate I just talked about. There will also be a water tube that goes from the water pump to the bottom of the powerhead, just look and see where it goes so you can put it back together again.
After the lower unit is down you will have to take the water pump apart so you can pull the drive shaft up and out of the center gear, thats the gear at the bottom of the drive shaft, not the prop shaft. There might be a bolt that holds the drive gear to the driveshaft. If there is take the prop shaft out plus the forward gear and put a wrench on the bolt and take it out. The drive shaft is what comes down from the motor in the center cowling, from the powerhead to the lower unit. After the drive shaft is out pull the prop shaft out of the lower unit and inspect the clutchdog and gears. If those ridges I talked about earlier on the clutch dog are worn or have rounded corners get a new one. If thier square thier ok and its the shifting cables need to be adjusted or the linkage is worn right where the shiting rod goes down right at the base of the powerhead though the center cowling.
If you can turn up a car or do a brake job you shouldn’t have much of a problem. If you’ve never done anything like this befor take your time and remember where each part goes, then just reverse what you did and put it back together. Theres O-rings and seals in the lower unit and water pump and its a good idea to change them anyway, plus new water impeller for the waterpump. Hope this helps and its the way to take a lower unit apart. Just take it apart and try to remember where the parts go and how they came out then just reverse the process. I know it sounds harder then it is, just take your time and remember and use a pencil and paper to write things down in what order they came apart. Message me if you need help and I’ll help. 
Thanks for the detailed explanation mossydan! I’ll give this a try and let you know if I have any questions.
Your help is greatly appreciated!
Just take your time and remember how things go back together and try to figure out what each part does as you take it apart, it makes it simpler to put it back together if you know what each item does. Good luck and if you need help message me.
Ended up having to defer to a mechanic…diagnosis: pinion gear split in two….estimated repair cost = $1650!!!
I’ll either have to try and tackle this during the winter myself or….. anybody looking for a side project for the winter?
Thanks for all the help.
You will need to pull the prop shaft and that requires some special tools. I would not attempt the re-build.
Like I said earlier, I dusted the lower unit on the same motor. My cost for the rebuild was $600. That was a few years ago. Try calling around for another estimate. The guys at Maplewood Marine did mine. (651) 776-0645 Also, try the bone yard in the other link.
For $1650 you could probably find a decent used motor.
-J.
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