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Johnson 33 HP 1070

G

Goodwrench

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Hi everyone, new to forum. First off I am a mechanic, just not Marine. I repair light and medium duty equipment everyday. I pulled the lower unit off of my 33 HP Johnson 1970 due to oil leaking from the weep hole when running with muffs. I just bought the motor and he told me he put a new impeller in. Question #1 there is a o- ring at the top of drive shaft just below the splines in a machined groove that looks like it could be for an o- ring but the other end of the shaft looks the same and no o- ring. Does the o- ring belong there. Question#2 where the drive shaft comes through the water pump housing there is no seal or o- ring. Is the top of housing just open or is something missing. Question#3 shifter shaft bushing is shot are special tools required to remove and replace it. Thanks for any advice you can give me.
 
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Welcome. There is an o ring at top of driveshaft to hold in grease or anti sieze and to keep out moisture. A rod of just the right size can go through the gear housing and catch the bushing to push it out from the bottom. There is a gasket along with the shift shaft O-ring used on some models.
 
The o-ring fits at the top groove ( on the driveshaft) .----Keeps water out of the splined joint !!----Very important.-----No visible seal on the pump housing .-----Shift rod bushing can be driven out with special tool.---Or run a 5/16-NC tap in it , pull it out and replace with new bushing and o-ring.
 
Here's what I made....it's pretty universal. It utilizes a metric tap and bolt, size 7mm x 1.00. Tap first about 2/3 way into bushing, then thread in tool to pull out with plate resting on top of housing. I can actually reuse the bushing if I want.
 

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The groove at the bottom of the drive shaft is to square off the ends of the spline grooves at a particular distance from the end. That establishes how far it drops into the pinion gear. In other words, it is not for an o-ring, but the groove at the top end IS for a very important o-ring.

Gotta appreciate the engineering that went into these great motors.
 
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