Now on the outside of the boat you'll need to remove the cotter pin and nut that keep the prop on the shaft.  You may need to put some vice grips on the shaft to hold it, make sure you place a rag between the metal of the shaft and the vice grips, you don't want to damage the shaft.  Remember the shaft nut is reverse threaded.  Turn it to the right to loosen it.  Like the retaining cup on the other end, the prop is keyed to the shaft and may need some love taps to get it moving. 

Once the prop is removed, you can remove the shaft.  It will fit by the rudder (barely) be careful though, bend the shaft and you will be spending a pretty penny to have another machined.  Right about now you will discover that your cutlass bearing needs to be replaced.  Mine certainly did.  The rubber came loose from the metal, and was worn to nearly nothing.  I don't know if it's the original, but it had certainly been around the block a few times.  In a perfect world with a perfectly straight, and aligned shaft, you might get a 1,000 hours from a cutlass bearing.  In the real world it will probably be less.  The easy way to check for wear is to try and wiggle the shaft the next time the boat's out of the water.  If there's any play in the shaft what-so-ever, it's time to replace it.

Removing the old Cutlass Bearing:

The measurements here are what I used for my project, yours may vary.  

Here's my rig in action

Click to see full size image

If the bearing is so frozen in place that this method doesn't work; the alternative is to place a hacksaw blade through the center of the bearing, then hook up the hacksaw frame and handle, and carefully cut through the bearing.  Be careful not to damage the inside of the bearing housing.  The bearing press is by far the preferred method, if it works.

Making Measurements:  You'll need four measurements to order the correct seal for the stern tube and the cutlass bearing.  You'll need to know the outside diameter of the stern tube, the diameter of the shaft, the inside diameter of the bearing housing and the length of the bearing.  I just took a piece of paper and pressed it up to the stern tube to make an impression, then measured it with a machinist's rule. (1 1/2")  I used a caliper to measure the shaft. (1") The bearing surface looked pretty pitted; the shaft may need to be replaced.  The bearing housing I.D. is 1 1/4" by 4" long.

I'm installing a PSS Shaft Seal and a new cutlass bearing.  My suspicions were confirmed by the machine shop; the bearing surface on the shaft is beyond repair, so the shaft will have to be replaced.  I also decided on a bigger propeller.

Increasing the propeller size will lower the R.P.M.s but I have a few I can spare.  I'm certainly not doing anything dramatic with this modification, but running wide open I found I can over rev the engine slightly.  Running at full throttle I was turning around 3,600 R.P.M.s, however,   Universal M-25XP Specifications suggests I should be running around 3,200.  I don't think this is the original propeller.  Something happened in this boat's history, and there have been repairs made around the area where the propeller is located.  Judging by the short cuts taken to affect repairs; if the propeller was replaced, I'm betting not much thought went into its size and design. (see: bondo)  

Do your research and find out what will work for your boat's configuration.  The more you know the better a decision you can make and the more comfortable you can be after having made it. 

The new shaft is being fabricated at Ellis Custom Propulsion Systems.  I ordered a 3 bladed 15 x 9 Michigan Wheel prop from Tacoma Propeller.  The folks at Catalina Yachts were very helpful and prompt in letting me know what was supposed to be installed.

I'm also installing a Prop Protector.  So I'm making a deal with all the crab fishermen on the St. John's river between Green Cove Springs and Mayport.  I won't cut you crab trap lines, if you don't put your crab pots in between those red and green things... I believe they're called channel markers.  I think that's a fair deal.

The reassembly is straight forward.  Taking it apart is the hard part. 

A few notes on reassembly; clean up the hole where the cutlass bearing is going with some fine sand paper; I used 400 grit.  It will make assembly much easier.  Make sure you put the vent line for the PPS shaft seal as high and as close to the centerline as you can get it.  Make sure it is securely attached.  If it comes loose, or finds a way to get below the water line while the boat is in the water, it can flood your boat.  Don't forget to mask off the areas the zincs will be attached to the boat.  Zincs that don't make contact with the important parts won't prevent corrosion to the important parts.  Take it easy with bottom paint around the cutlass bearing, if you block the flow of water through the fluted rubber insert it won't cool itself.

The completed project:

Click on picture for full size image

Post Project Note:  The new propeller makes all the difference in the world.  The RPMs are right where they should be, and maneuvering at the dock was a breeze.  It almost looks like I know how to drive a boat now.

The Cost:

Cutlass bearing: $50.00

PSS shaft seal:  $200.00

Shaft: $415.00

Propeller: $390.00

Prop Protector: $230.00

Materials for bearing press and misc. stuff: $50.00

The Grand Total:  $1,335.00 so far

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