Drive train job nearly finished or... ?

[CalebD]

In the first picture I see something other than the cotter pin that you might consider.

I'd lose the collar zinc and go for a prop nut zinc instead. It's recommended there be a portion of the shaft exposed between the prop hub and aft end of the bearing equal to one shaft diameter to allow space for water movement through the bearing. With your bearing in deadwood you already have less flow than us strut guys (we have both ends of the bearing exposed) and obstructing the only water access with the zinc collar can’t help.

Here's a thought but not necessarily a recommendation. ...
snip
...
It caused a funny scene in the boatyard where I built her. The truck arrived for the trip down Pacific Coast Highway. We dragged her out of her spot in the yard and loaded her on the trailer. I jumped up inside with a garden hose and fired the engine up for a final test. Water was gushing out the bearing as it should with my installation but it was certainly not conventional. The yard 'experts' started running around yelling at me to shut her down, there was a major leak at the prop. It looked like a scene from the children's story Chicken Little, "The sky is falling, the sky is falling!!" I said nah, no worries, it’s supposed to do that. They said, “Huh? Are you sure?” They were certain I had a disaster brewing.

I was wondering about the collar zinc obstructing water flow around the prop once I installed it. Our old shaft used a Castle nut with a cotter pin to secure the prop and I decided to go with the double nut prop locking system precisely because I could get a zinc with a nut embedded in it to act as the locking nut. Being a creature of habit I bought a collar zinc instead as it was cheaper then the zinc with a bolt embedded. I was so happy I could fit the collar zinc on there as our old prop shaft was short and left only about 1/2" for the zinc to fit between the prop and the deadwood which left me with the unenviable task of hacking away at a 1" collar zinc until I got it down to a size that would fit. Next time I have to replace the zinc I'll go with the zinc nut embedded in it.
More on the collar zinc itself. I'm not sure that this is apparent in my photo #1. There are gaps between the two halves of the zinc and the bolts are tight. I'm thinking I'll have to file down the little copper ball connectors that are inside of the collar zinc so I can get the two halves to mate properly. I'm certain that in the past when I hacked away at the zincs I used that these copper ball/connectors had fallen out allowing the collar pieces to mate easily.

I love your story about your self lubricating cutless bearing.

[CalebD]

Hey, I have that same ladder!

The set screw on the shaft coupling looks like a meat hook to me. Does it have to be that long. I just imagine something getting caught on it and making an unholy mess.

My key ingredients for cleaning an engine room: soap(your choice), beer, favorite tunes.

Spring is coming!!!!
russ

You are right. That set screw is huge and I should have seen that as a liability when I got my stuff from the prop shop. I'm not sure I have time for a trip back to the prop shop before launch so it will get wired as is: a meat hook.

I'm working up to a big cleaning session back there. It's never been cleaned since we got the boat 10 years ago. I may have to get some over proof beer to help keep the work flowing smoothly.

[CalebD]

I just had the yard remove the prop shaft coupling to gain access to the keel bolts. After, they reinstalled the coupling and two set screws. There is no hole in the set screws to wire them so they cannot back out. Should there be such a hole?

I'm not the expert here, just one of those who ask questions. Since I'm not really sure I'll still offer my opinion.

At a minimum I'd suggest getting some SS seizing wire and wrapping it around your screws and around the coupling. I think the answer will be that the set screws are supposed to have a hole in them for wiring them firmly in place.

[CalebD]

Caleb,
As odd as it may seem, the correct way to install the prop nuts (according to the ABYC) is to install the thin nut first and then the thicker one. The theory is that the thicker nut will "deform" the thinner nut against the prop creating a better "lock". When I read this in Practical Sailor I was quite surprised since almost every installation that I've seen has been done "thick nut first".
Tom

Damn! I'm sure glad I posted these half baked pictures of a job not-so-well done. You all have given me some great feedback.

I thought about this at the time I installed the nuts on the shaft but this idea did not occur to me. It is a good thing the cotter pin has not been splayed so I can easily go back and change this set up.
That is one subtlety that I would not have picked up on.
Thanks.

[JOHN COOKSON]

I Was Shooting From The Hip - No Research Was Done

Mmmm, no I did not use loctite to lock the threads. Is this one of those ABYC recommended practices for prop nuts? I'll have to buy some loctite it so. Which color to use, blue?
http://www.loctiteproducts.com/threadlockers.shtml

I don't know what ABYC specifications are for this instillation.
I don't know if loctite is any good underwater.
Part of my thinking was if you could get some kind of compound between the nuts and the shaft it might cut down on the corrosion and make removal easier when the time came. Loctite was the first thing that came to mind. Paradoxically something that would lock the threads might also make the nuts removal easier at a later date.

TRUE GRIT

[Administrator]

This stuff? No experience with it.

Bill

[Mo]

Good sound rudder.

They sure made a Heavy Duty skeg and rudder on that boat. I love seeing things that were built well. There are loads of boats out there that compromised the safety of the rudder for speed. For the most part there is never a problem. That one of yours could probably get away with banging on a rocky shore for a couple of hours and still be able to steer the boat once pulled off ... allot to be said for HD gear.

[CalebD]

They sure made a Heavy Duty skeg and rudder on that boat. I love seeing things that were built well. There are loads of boats out there that compromised the safety of the rudder for speed. For the most part there is never a problem. That one of yours could probably get away with banging on a rocky shore for a couple of hours and still be able to steer the boat once pulled off ... allot to be said for HD gear.

Thanks Mo. Yes, my Tartan 27 is from 1967 and is quite over built or, as you say, heavy duty. I like to think of this boat as the 'Cadillac' of boats back in it's time. Tartan was just starting their first production run of 'glass' boats back then and paid a lot of attention to making everything quite 'beefy'. The designers were the highly respected Sparkman & Stephens firm.

I was amazed the first time I stepped aboard a friends MacGregor 26' S model boat from the 1980's. The spars, the hull/deck thickness, cleats, winches, stays was so much smaller then my boat which is only 1' longer (and probably more then twice the weight). The M 26' S seemed flimsy by comparison but it was a good sailor for appropriate conditions and is pretty easily trailered. The M 26' S could even sail faster then my boat (quasi planing hull with water ballast) but I would hate to be on it in anything resembling rough water, especially with an outboard motor hanging off the end (there has never been an A4 in a MacGregor sailboat as far as I know).

[CalebD]

Packing? Got the wrong size? NG

I repacked our stuffing box about 8 years ago and I thought for sure I used 1/4" packing so I bought some new 1/4" packing material (GFO) to do the job with. The problem was that I had to really cram it into the stuffing box and it got hot after a short bit of motoring.
I found the remainder of the packing I had used 8 years ago and it was 3/16" stuff so I removed the newly installed 1/4" packing and replaced it with newer 3/16" GTU. My preferred removal tool was a drywall type screw. The Dentist's tool that I dropped is still in my bilge waiting for me.
The 3/16" packing went in SO much easier then the 1/4" stuff which was just too thick.
It will be much easier to sneak up on the right pressure for a few drips while motoring now that the right size packing is in there.

[jstaff]

I wouldn't remove any metal from the copper contact on the collar zinc. What's more important, zinc to zinc contact, or zinc to shaft contact?

I tap lightly on my zinc as I tighten the screws to assure that it's well "set" into place.

You could try to put a little bend in the cotter pin so the eye might press against the lock nut but I wouldn't be to worried about it.

I assume that the prop was put on without lubricant or anti-seize.

[JOHN COOKSON]

Maybe I'm not Understanding The Issue Here

I wouldn't remove any metal from the copper contact on the collar zinc. What's more important, zinc to zinc contact, or zinc to shaft contact? I tap lightly on my zinc as I tighten the screws to assure that it's well "set" into place. .

If the zinc is not in good electrical contact with the shaft protection will be reduced or nonexistent.
This means all metals bright and shiny when the zinc is installed and the zinc in firm mechanical contact with the shaft.

TRUE GRIT

[jstaff]

If the zinc is not in good electrical contact with the shaft protection will be reduced or nonexistent.
This means all metals bright and shiny when the zinc is installed and the zinc in firm mechanical contact with the shaft.

TRUE GRIT

Yes, bright and shiny, including the intact copper contact that crushes between the shaft and zinc.

[edwardc]

I came across a neat trick this winter for shaft zincs. I plan to try it this spring.

As the zinc erodes, it will often erode around the clamping screws, causing the zinc to prematurely loosen and lose good contact with the shaft, drastically reducing its effectiveness. In extreme cases, the zinc will even fall off while there was still lots of mass left.

The trick involves painting the screw heads and nuts, and a little of the surrounding area, with nail polish after the new zinc is attached. This insulates the area around the screws, protecting them from early erosion and keeping your zinc atached and effective for as long as possible.