Shaft protection?

notop

Seaman Apprentice
Joined
Feb 24, 2011
Messages
37
1986 125 Hp Force... went to remove lower unit for inspection of water impeller. Has been done annually for 3 years or more, never been an issue. This year however, I had a real bear of a time getting the LU off... once I finally did, it appears as though the rubber/plastic-y collar that is supposed to provide some protection to the shaft splines out of the powerhead had fallen or slid down the shaft. The shaft splines and powerhead splines show signs of surface rust and corrosion.
I've cleaned everything up as best I can with a wire brush on the shaft and a wire bottle-brush on a stick for the powerhead splines, followed by a power-washing, so I think I'm OK as far as getting it back together again. But I want to prevent future days of wrestling with this same issue. The rubber/plastic-y collar idea seems a bit lame if it's just going to fall down again and I don't think I want to try gluing it in place.
I've been told not to put grease on those splines as it gets shoved up to the top of the shaft and causes bent shafts through excessive compression forces. I thought of coating with oil might suffice, but maybe the heat will cause the oil to harden over the season and turn it into a gunky glue? So what can I do to prevent the spline area from corroding itself onto the powerhead again? Any suggestions?
 

gm280

Supreme Mariner
Joined
Jun 26, 2011
Messages
14,585
Don't know about the "plastic-y" part you're talking about, but you should be putting grease on the spines themselves. NOT the end of the drive shaft, because that will create a seal and not allow the drive shaft to seat properly, but certainly on the splines. Otherwise you WILL continue getting rust on them and one day it will not come back out again. And since the mating splines in the power head (actually the engine's crankshaft) will have to be change at that time, the cost is going to be a deal breaker then.... On some engines there is a recessed area for an "O" ring to help keep out water of the splined area.
 

jerryjerry05

Supreme Mariner
Joined
May 7, 2008
Messages
17,923
Grease on the splines.
The rubber sleeve is there for protection.
It's kept in place with a metal collar.

One of my motors has rust and corrosion on the drive shaft.
The other not.???
I think the pump or the waterpipe is leaking? Maybe the adaptor plate?
Or allowing water up in there somehow.I rub grease on the shaft and it helps for a while.
 

gregmsr

Petty Officer 1st Class
Joined
Sep 20, 2006
Messages
391
That rubber sleeve is always a PITA keeping it on the end of the shaft while heaving the shaft up thru the leg.
I have taped it on before just to hold it in place.
Then, every time I can't remember which way it is supposed to go (idiot)........metal ring on top or bottom.. it always falls off when I pull the lower off, then I question myself if it is put back on correctly (again, idiot).....
 

Nordin

Commander
Joined
Jun 12, 2010
Messages
2,428
As jerryjerry mention, the rubberseal should be hold in place by a metal coller whitch is pressed at the driveshaft.
Put some grease at the splines not at the top of drveshaft.
Check for the coller if it is the but not in place try to glue it in right place wjth some Loctite 495 superbond or equal.
 

jerryjerry05

Supreme Mariner
Joined
May 7, 2008
Messages
17,923
The collar goes on first with the groove facing up then the rubber goes on with the squared off end up.
Or down, it really doesn't matter as long as it's on.
Yes grease on top of the drive shaft is not a good idea.
 

Nordin

Commander
Joined
Jun 12, 2010
Messages
2,428
When the driveshaft goes in to the splines in the crankshaft the rubberseal will be compressed. It will seal and protect the splines in the crank and at the driveshaft from water and from rusting.
With the rubberseal in place and then coating the splines with some grease, you will have double protection from water/rust.
 

Frank Acampora

Supreme Mariner
Joined
Jan 19, 2007
Messages
12,004
Square end of the rubber goes into the collar. Tapered end matches a taper on the crank shaft and goes up. Anti-seize will work as long as it is not copper or graphite.These will speed corrosion. Some consider never seize in salt water to be ever seize.
 
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