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labrador-guy.
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December 19, 2020 at 9:33 am #225555
Is it possible to make a CD/AD Johnson gear case work on a 1958 QD19 Johnson? I recently purchased a 1958 Johnson 10hp with the gear foot missing. Original case seams to be scarce. I would like to save the old girl but it might become a parts machine. I might need to find another ’56/’57 motor with a bad power head and use the five bold leg to bring her back to life! I think the ’58 power head will work on the older leg.
Any thoughts or Ideas?
daleDecember 19, 2020 at 10:56 am #225558Good question indeed. I’m pretty sure this can be done, but you will have to investigate further. I think this will work out because the shock absorber driveshaft used a larger diameter lower gear housing bushing, that is the same diameter as the driveshaft on the 10hp….
But, you will need the 10hp driveshaft, upper bushing/seal, and prop shaft, along with the 10hp shift rod. You will need to remove the original shift rod detent spring because the 10hp shift rod does not have the detent reliefs in its shift rod.
Let me know what you discover, have always wondered about this….December 19, 2020 at 11:14 am #225559Dale, I have responded to your parts ad
December 19, 2020 at 7:50 pm #225586A ’58 to ’63 QD or Sportwin gearcase is a straight bolt on job. No machining required as would be the case trying to fit a CD or AD gearcase to the ’58 QD. The smaller horse gearcases would need the lower driveshaft bushing reamed out to accept the larger ten horse driveshaft and then there’s no guaranteeing there is enough meat in the CD/AD gearcase bushings to do it. Then you’d have to make sure the ten horse gears will fit into the CD/AD gearcase as some pinions were key driven and others were splined, depending on the year.. It would probably be easiest to cut both driveshafts below the powerhead and splice one together with the correct spline on top to avoid any problems with the gears, water pump, and bushings. Then the $64 question is, are the bolt patterns to the exhaust housing the same? They look the same, but are they? I know the skeg bolt patterns look the same between the two models but they are slightly out of alignment to each other.
I did use a later 9.5 horse gearcase once on a QD but it seems to me I had to switch some internal parts around to make it work. Can’t remember exactly what I did as that was a few years ago now.
December 19, 2020 at 8:30 pm #225592Well that sounds like more than I can do with a file and a drill! OMC really cheapened this model up. I see the transom clamps and the center section between the clamps are all smaller and weaker. I never thought about a 9.5hp foot before. I have some early fifties LU parts and the bolt holes won’t line up either. Will see what Mister Ede has to say.
thanks dale
December 19, 2020 at 9:46 pm #225596There’s a 1961 10hp gearcase on Ebay right now, part #376775. Has a small chunk missing off the back of the cavitation plate but can probably be repaired. Only other issue is the guy is selling the skeg piece separately from the gearcase and he wants more for the skeg than he does the case!
Bob
1937 Champion D2C Deluxe Lite Twin
1954 Johnson CD-11
1957 Evinrude Fastwin 18
1958 Johnson QD-19
1958 Johnson FD-12
1959 Johnson QD-20“Every 20 minute job is only a broken bolt away from a 3-day project.”
"Every time you remove a broken or seized bolt an angel gets his wings."December 20, 2020 at 11:24 am #225609#225596
“There’s a 1961 10hp gearcase on Ebay right now, part #376775. Has a small chunk missing off the back of the cavitation plate but can probably be repaired. Only other issue is the guy is selling the skeg piece separately from the gearcase and he wants more for the skeg than he does for the case.”
Thanks bob, good to know that part number. I need a complete unit. Might be to expensive to fix this motor. It needs a coil and the usual stuff. The paint is not the greatest but it would fit in with the other money pits that are in my shop! I think member ede is gonna fix me up with something. I can’t save them all I guess!
dale
December 20, 2020 at 12:20 pm #225610I have been comparing part numbers on Marine Engine,com between a 1958 QD19 and AD/CD of the same year. Gear case, forward gear, reverse gear and pinion are all the same. Propeller shaft is different. I knew that for sure, drive shaft is much longer and no shock absorber in the QD.
interesting for sure
daleDecember 20, 2020 at 12:58 pm #225612I’ve got a complete QD-22 gear case if you need it still.
December 21, 2020 at 4:56 pm #225730I have been comparing part numbers on Marine Engine,com between a 1958 QD19 and AD/CD of the same year. Gear case, forward gear, reverse gear and pinion are all the same. Propeller shaft is different. I knew that for sure, drive shaft is much longer and no shock absorber in the QD.
interesting for sure
daleThat’s what I noticed also, which is why I figured the OD of the 10hp driveshaft and the CD/AD/QD lower diameters were the same………1958 parts book uses the same gear housing for the CD/AD as the one used on the 58 QD… Same part number used for both models in 1960 also, didn’t look any further….
So, if you can find a 376775 gear housing (empty-just the two housing pieces), this will work on your 10hp. But, you will still need the 10hp driveshaft, and these are getting tough to find in decent condition. You will also need the 10hp upper bushing/seal hsg and prop shaft as well.
Now, I know there was a change in the driveshaft/pinion at sometime, the original 10hps used the CD/AD keyed pinion. Later model 10hps used a splined driveshaft/pinion set up, which was different than the pinion set up on the smaller 5.5/6hps…
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