1968 Johnson 9.5hp Scored Driveshaft and Gearcase

rcspott

Seaman Apprentice
Joined
Apr 9, 2010
Messages
31
Have a 1968 Johnson 9.5 with an upper gear case brass bearing (?) and drive shaft that are scored. The scoring is about 2 pieces of computer paper thick and deep and about 2 inches long. Is this something that is fixable? If it is not fixed will the gear case leak oil past this scoring? What actually keeps the oil from coming up and out? The motor runs pretty good for sitting many many years and is pretty clean. Have not done any carb work or further inspection of points etc. I just acquired this motor off of CL. Does it have any parts value on eBay. Live in Bozeman MT
 

F_R

Supreme Mariner
Joined
Jul 7, 2006
Messages
28,226
That is wear and tear, often accelerated by low oil and/or water in oil. The bushing is cast into the gearcase and cannot be replaced. Worse yet is the one just above the pinion gear. They wear and allow sideways movement of the pinion gear, causing gear tooth wear. Likewise, it is cast in and cannot be replaced. An oil seal keeps the oil in and water out. Unless the shaft is slopping around loose in there.
 

F_R

Supreme Mariner
Joined
Jul 7, 2006
Messages
28,226
You MAY be able to have the bushings machined out and replaced. But you still have the worn shaft and gears.
 

racerone

Supreme Mariner
Joined
Dec 28, 2013
Messages
39,225
The problem here is the location of the hole.-----Drilling the hole out is not the solution as it puts the pinion in the wrong location.-----The hole needs to be bored in the correct location and is not easy unless you have the drawing / blueprint for the gearcase.------Look at placing a want ad on ----aomci-----website.-----But this is a common failure so it is " buyer beware ".
 

F_R

Supreme Mariner
Joined
Jul 7, 2006
Messages
28,226
To bore out the bushings, it would have to be set up in a milling machine, centering on some area that is concentric with the original bore. I think I'll experiment with it someday, when replacement gearcases become too rare or expensive.
 

racerone

Supreme Mariner
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Dec 28, 2013
Messages
39,225
Agreed I have a bunch of good gearcases and one NOS gearcase assembly.--One day I will make a fixture to repair these bushings on the 6 and 9.5 gearcases.
 
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