Hi All,

I'm slipping my boat this weekend (Tophat 25) and have a good hit list of work to do.

One item of concern is the age of my shaft seal and shaft bearing... Both new in 2011, that means they are almost 8 years old.
Shaft Seal: Volvo Penta Shaft Seal 828254 (supplied by fenquins marine, Ingleburn)
Shaft bearing brand unknown but replacement proposed is: Cutlass prop shaft bearings non metallic Johnson product
boatbits.com.au/propellers-hub-kits/cutlass-bearings/cutless-prop-shaft-bearings.html/

Service life as far as i am aware 6-10 years for the shaft seal and dependent on engine hours. Engine has about 300 hours on it at present and i likely wont do more than 100 in the next two years before its next slip...

Both look to be in good condition with no dripping from the shaft seal which has not been regularly lubricated and i will be lubricating it if i don't replace it...

Replacement cost is about $400 materials plus labour which I should be able to do myself after a few more youtube videos....

Other items (let me know if I've missed any..)
- Annodes
- Ball valves (age unknown however likely 20 months) - bronze..
- Prop Speed - 200ml DIY
- Rudder bolts - SS 316
- Antifoul - Altex No.05, 2 x 4L

The question is - Do it now or do it in two years? I don't see the point of spending the money and wasting two days working on it unless its due to be done...

Cheers!!!

Only you can decide if it needs to be done. Dive and wobblel the shaft ln the cutlass. You can get away with a fair bit of wobble.
If you do the seal, beforehand measure and buy new coupling nuts and bolts. If the old ones don't want to come out, get out the small grinder with a cut off blade and cutem off. Not 2 days.
If you prepare tools and parts. 1 day most, as long as shaft is ok.
If you areplanning to keep boat, i would by parts, and prepare tools, check condition when she is out and then decide.

Gary

Thanks so much for your reply Gary. I'll have a play and see how much wobble there is. I'm thinking the shaft seal has a bit of life left I reckon so if limited movement then I'll leave it.

Greetings Fellow Top Hatter,

Good to see you are putting on 4 coats of anti-foul, remember it will be a minimum of three years before you have to slip again to redo.

The SS rudder bolts, I actually use threaded rod with locking nuts, will only need to be replaced if they are showing signs of pitting.
I carry an extra three as they are easy to replace if needed, which I've only done once in the last 10 years.

Annodes should need replacing about every three years on a Top Hat, but sooner if showing signs of reduction.

Prop speeds requires 2,000 plus revs and speeds over 10 knots to work.
I've tried it a couple of times on Seaka with poor results so not worth the money.
A plastic bag over the prop for those long periods of non use is a better option.

If the ball valves are tight, or firm to use, they should be good.

If your'e a Mk 2 or 3 you should check for osmosis after you have wet sanded the existing anti-foul.
They show up as shallow domes from 20 cent size and up.

Now the cutlass bearing.
If your shaft comes out directly to the rudder [ie not out to the side of the rudder] you will have to remove the rudder.
This is easy if you are lifted out and drop the rudder before they put you down, but if not you will require 800 mm clearance below the keel and horizontal room to drop the rudder out to allow removal of the shaft. Length of the new cutlass bearing should be 150 mm and if it doesn't fit the tube it will need to be turned down in a lath so as to remain truly in line with your motor. Fix in place with industrial grade Araldite.

What I'm really saying if its working and you have no thumping of the prop shaft and its not loose as per Gary's comments, leave it alone!

Enjoy your time at the slip as I know its a dawn to dusk task

Thanks Phillip! I see your posts on the TH forum and facebook page and quite often refer to the info on the forum!

Yes, hoping to get 4 coats on. I've got a Mk 2. Yes replacing the rudder bolts with threaded stainless 316 rod and nylocks..

Yeah I hear what you're saying about the prop speed but my little prop spins pretty quick and the propspeed lasted for 18-20 months last time so I'm applying it again = $200 200ml DIY kit....

Replacing the ball valves and one of the two skin fittings (i buggered the thread on it...). They aren't bad but the boat probably wont come out of the water for another 3 years as you say...

Great tips on the cutlass bearing!!! Here's a little video clip of the shaft movement... Looks like max 2mm movement? ALso the prop is a little loose on the shaft. Any thoughts on this?

No thumping but a little bit of a vibration as the motor gets to full revs and then it settles...

UPDATE!

The shaft seal and bearing are both staying put! The seal will be done next time and the bearing has relatively limited movement...

The issue is/was, the prop had a lot of additional movement as you can see in the video due to the key boring out the bronze a little as you can see in the photo of the prop prior to the repair. All fixed now, got the prop re-keyed, serviced/cleaned and balanced at Austral Propeller.

As you can see in the photo, the prop is a little pink and has seen a little electrolysis. Any tips on how to check if I have electric currents running down my prop shaft?? Anyone experienced this?

Also - I have a 2kg anode about 300-500mm away from the prop.. Is this too much anode? Could it be creating electrolysis problems?

As you can see in the photo, the prop is a little pink and has seen a little electrolysis. Any tips on how to check if I have electric currents running down my prop shaft?? Anyone experienced this?

Also - I have a 2kg anode about 300-500mm away from the prop.. Is this too much anode? Could it be creating electrolysis problems?

Don't panic. Better still, don't worry.
It is an old boat with an old (well used) prop.
What you are seeing on the prop could have happened 10 years ago. (or not).
Still got years left in it.

Gary

Hey Gary!

Appreciate your response again! Yes, 5 years left they reckon!

The prop was new in 2011 and so was the engine and running gear... You're right that could have happened at any time for a number of reasons, the new diesel setup, new battery installed last year, faulty solar regulator, neighbors / moored boats are bloody close and one of them has a generator on the deck... I'll have to do some reading! Seen any good articles.

Even if it keeps going a little more pink every year, as long as I get another 5 out of it I'll be happy :-)