72T Lower Unit Disassembly

[T….in Wisconsin]

With a frim grip and tug the prop shaft was removed.

Thanks Tub.

 

[The Boat House]

Unless there is some damage there is nothing (that I can remember) to stop it from coming out. The prop shaft slips into this adjustable bushing / bearing. It could be just suction keeping the shaft from coming out. Take the bushing out and see what happens. Looking at the drive shaft again I don’t think its necessary to remove the key to get the drive shaft out. Tubs

[T….in Wisconsin]

Moving on to the drive shaft. Per your earlier post, the gear on the drive shaft will slide off once the  prop shaft is removed. Found a piece of packing felt on the drive shaft.  Have you came across this? I may have to replace. I’ll reaccess after I get the drive shaft out.

T…

[The Boat House]

Somehow I missed your post where you have it apart. As far as the wad of goober – not a clue what that is. Tubs

[T….in Wisconsin]

Removed drive shaft and inspected drive gear. As expected there are sign of wear but not terrible.

I decided not to remove the drive shaft from the housing as the coupler is doweled to the drive shaft. I see no good reason to remove it.

Your castings look good. Without getting into the fine details what did you use to clean them up? 400 -1000 grit sandpaper &  scotch brite?

I thinking the fibrous goober is packing to restrict lower unit grease from migrating.

T…

[The Boat House]

Yep- typical gear condition, but serviceable. Years ago someone told me the pits carry extra grease improving lubrication. Sounds good to me. I believe the driveshaft assembly changed from 26 to 27 as it connects to the crankshaft. I’m not familiar with any other changes. I suspect your correct on your assumption of the fibrous goober. I don’t believe its factory.

Restoring the surface. A polish is the least aggressive. Keep reapplying and rubbing till it doesn’t get any better and you have removed the surface corrosion, reviling the original finish. I’m always trying different stuff. The Zephyr is different than all others I’ve tried as it drys to a haze that is easily removed. I find 0000 steel wool useful. A little more aggressive. I often use it on carburetors. The staining, where moisture has etched the aluminum, requires a much more aggressive approach. I get this 3M paper from Home Depot. Its the best I’ve found for wet or dry sanding. It’s available from 120 to 400. I wish it was available in finer grit’s but I can’t find it. You’ll want to use sanding blocks on parts like your gear case. After the 400 I go to the buffer. Ive been polishing since I got my first motorcycle in 1965. Every hobby I’ve been in has had aluminum to polish. If you want to try to learn how to remove that deep staining and restore the surface, start with something that is no longer usable or easily replaced. Its dirty nasty work and its no fun (for me anyway). Often the contamination in this early aluminum leaves you with disappointing results. Except for the flywheel I believe the rest of this motor has just received a hand polishing. Been a while.

[T….in Wisconsin]

I appreciate the nice pictures, product knowledge and advice.

Thanks Tubs.

[Author]

Posts