Lower unit leaking...can't get prop off!

[waflyboy]

Happy summer all,

I have a 1976 Mercury 500 Thunderbold 50hp. She ran great all spring when I was bass fishing, but the other day I went to prep her for some crabbing and found the lower unit leaking gear oil, apparently out of the prop hub area.

Looking at the diagram in the Seloc book, it seems like a safe bet the problem is one of the oil seals. Figuring I could likely do this job myself, I started to take things apart. First the prop nut, then the thrust washer. It didn't look like any other hardware was holding the prop in, so I figured I could pull her right off. Gave it a good tug but it wouldn't budge. Tried pulling, some tapping with a rubber mallet, PB Blaster... doesn't move at all.

Is there some other hardware that I'm missing here? Or do you suppose the prop is "frozen" on? Will try posting some pics when I get home. All help is MUCH appreciated.

Gotta get that crabbing gear in the water!

 

[Bosunsmate]

Re: Lower unit leaking...can't get prop off!

Yes frozen on.
Keep doing what you a doing.
Rotate prop so you knock around it evenly with a rubber mallet.
It will probably take quite a firm knock to get it moving

 

[waflyboy]

Re: Lower unit leaking...can't get prop off!

Thanks for the reply!. I gave it some pretty good whacks yesterday. Will try some more again today. Sure is frustrating!

 

[Bosunsmate]

Re: Lower unit leaking...can't get prop off!

Yep i remember all to well doing that myself.
If you can get hold of a three legged puller with long legs you might be able to slip the legs in behind prop

 

[waflyboy]

Re: Lower unit leaking...can't get prop off!

I found this on the web:
The Ultimate Propeller Removal Tool

You think it will do the trick?

 

[Bosunsmate]

Re: Lower unit leaking...can't get prop off!

I cant see why it wouldnt work unless the props really seized on more than the threads in that contraption could handle.
The girl in the yellow bikini works for me

 

[waflyboy]

Re: Lower unit leaking...can't get prop off!

LOL no kidding!

Thanks for the advice. Will give this contraption a shot. Figure I should be able to sell it after the job is done!

 

[waflyboy]

Re: Lower unit leaking...can't get prop off!

Another quick question: the diagram for this motor shows both a tab washer and a thrust washer behind the nut. But when I removed the nut I found only a thrust washer. Are they mutually exclusive? Or should I plan on buying a tab washer and using both?

 

[Bosunsmate]

Re: Lower unit leaking...can't get prop off!

Mine had only a thrust washer but i would suggest its probably worth getting. $4 or so

 

[waflyboy]

Re: Lower unit leaking...can't get prop off!

Will do! Thanks!

 

[waflyboy]

Re: Lower unit leaking...can't get prop off!

A few pics, in case anybody is interested. These are the two hardware items I removed from the prop shaft. The prop should just come off now, right?

When the Proptopuss arrives I'll give it a try then provide a report!

 

[Bosunsmate]

Re: Lower unit leaking...can't get prop off!

Yes it should

 

[jimmbo]

Re: Lower unit leaking...can't get prop off!

Try some penetrating oil. When you reinstall the prop apply grease or a non hardening gasket sealer(quicksiver Perfect Seal) on the splines to prevent it from happening again

 

[waflyboy]

Re: Lower unit leaking...can't get prop off!

Good deal, guys. Thanks for the advice. Another question: how easy is it to damage other parts of the lower unit while trying to remove a prop? Hitting the prop with a rubber mallet and yanking with a prop puller certainly puts strain on other parts of the drive, right?

 

[Chris1956]

Re: Lower unit leaking...can't get prop off!

Titl the motor all the way up. Apply penetrating oil all around the splines. Let her soak a while. Now take a 2X4 and pry between gearcase and prop blade. Change blades a few times. See if it will come off. If not, prop puller is next step. If that fails, you will need to destroy the prop to get it off.

 

[relics hunter]

Re: Lower unit leaking...can't get prop off!

I went through this when my older mercury 115 spun its prob. I ended up renting and modifying this puller from advance auto it worked great. Had to wrap all the prop blades with a ratchet tie down strap to pull the prop and then as you can see in this pick I had to move some nuts and bolts around on the puller and it worked perfect on the hub.
hope this helps
Jay

 

[waflyboy]

Re: Lower unit leaking...can't get prop off!

Thanks for all of the help and advice, everybody. Here's what happened next:

My "Proptopuss" arrived a few days ago, and today I finally had time to try it out. I set it up according to the directions, and after some trial and error got it working. (See pics below. Getting it set up would be much easier with two set of hands, as the chains tend to comply with the force of gravity until you've got some tension on them. I used duct tape in lieu of extra hands.) After much huffing and puffing, the prop popped off.

So, here's what I found: (see pictures) The prop's rubber hub seems to have stayed on the prop shaft. So what now? Do I get out my hacksaw and cut this sucker off? And then what about the prop? I've read that typically only a prop shop can properly install a rubber hub... any truth to that? (It probably wouldn't hurt to re-prop the motor anyway.)

Thanks again for the guidance!

 

[belairbrian]

Re: Lower unit leaking...can't get prop off!

looks like time for a 3 jaw puller like Jay used.
If that doesn't work time for a cut off wheel.

As for the prop the blades look bent from the puller and the hub is out. Time for a new prop.

 

[Bayou Dave]

Re: Lower unit leaking...can't get prop off!

I cant see why it wouldnt work unless the props really seized on more than the threads in that contraption could handle.
The girl in the yellow bikini works for me

Me too!!

 

[Fleetwin]

Re: Lower unit leaking...can't get prop off!

When you put it back on, grease the splines and pull it once/year.