Johnson TN27 lower unit assembly

[Michael Purpura]

After removing the lower unit of my TN27 I replaced the impeller, installed new gaskets and then attempted to slide the lower unit back onto the drive shaft. I can get the shaft and the clutch spring in to a point where the housings of the lower and upper units are separated by about 5/8″. I have tried with the neutral cable in neutral and engaged with no success. I have also looked on http://www.boatinfo.no in the Johnson Service manual. If anyone out there has a tip could you drop me a quick note.

As always I appreciate the help and hope someday I can return the favor.
Best regards,
Mike

[frankr]

My mother used to say there is more than one way to skin a cat. I’ve never done a cat, but have had a few TN’s apart and there is more than one way. Anyhoo, I suspect you now have the clutch plate/water pump installed onto the upper housing, with the lower shaft & clutch sticking out the bottom, right? If I’m guessing right so far, I’d say the splines on the bottom of the shaft are not aligning with the splines in the pinion gear. Simply turning the prop while sliding it together may be all it need. OR, pull the clutch assy off the upper drive shaft and insert it into the lower unit first, turning the prop as before. Then you can see what you are doing as you put it to the Double-D drive shaft end.

[Michael Purpura]

Thank you Frank for the illustration and the tips on how to assemble the lower end. I will give that a try and let you know.
Best regards,
Mike

[Michael Purpura]

Frank I found the problem. The pinion gear moves out of alignment with the cast in bronze bearing. By turning the motor sparkplugs up and resting horizontal on my bench, the lower unit slid on like it was made for it. Now a little gear oil and I am almost ready to fire her up.

Thank you again for your help,
Mike

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