Converting our workboat to tugboat.

Stuffing Gland space

They've painted you into a corner there with that gland you are not going to be able to re-pack it in situ but if you're changing the cutlass bearing and pulling the shaft repacking it is highly recommended.

If re-packing becomes a possible the teflon packing is much better.

What SamSam said is very important - They are water lubricated and are DESIGNED to drip!
To adjust (only do in the water) tighten the nuts evenly say 1/8 turn - it should feel like the same pressure on both - run with shaft turning at idle and check and is really only needed when drip frequency is 10s or less.

The little plug in the middle right may need to be loosened to vent air at first launch if you put fresh packing in till all beds in.

 

Thank you gentlemen this is a great learning experience.

The nozzle setup looks like it would be a nice setup. Can these be purchased through a supplier or are they only done at a shipyard?

I am a welder by trade so can handle fabrication but this would be a challenge...

 

I've replaced them, diagnosing them was above my pay scale. I googled it and this came up

http://www.cruisingworld.com/how-to/maintenance/check-the-shaft-bearing-on-the-hard

Whether they dry out, I'm not sure but I would bet they do.

I also saw this, which might apply to your strut/sterntube/shaftlog as it looks to be aluminum.

In the meantime Andy has posted and it looks tight, but you might be able to take the nuts off and back the follower up enough to get packing rings in one at a time, shoving them down in with the follower. I'm not sure how you would replace the packing without having the shaft in place. You could unbolt the coupling from the tranny, loosen it from the shaft, back the shaft out enough to take the coupling off and then repack without tightening the follower too much, put the coupler back on, slide the shaft back up, re-bolt and tighten the coupler back on and then adjust the follower to compress the packing. Then have a beer.



Here is the packing




done like this (I'm not so sure we skived the joints, but it looks like a good idea. At any rate , we staggered them.).



Getting the old packing out might be a hangup. They have these extractors in different sizes, which work well.

 

I don't understand this part "is really only needed when drip frequency is 10s or less." ? does that mean drip frequency should be at least one drip every 10 seconds? (at least 6 per minute?)

Also, does the air need to be vented every time the boat is taken out and the water runs out the stern tube?

 

Hi Sam,

Thank you very much for all that information.

I have to head out and barge a load this morning then I am going to look over the boat with your email at hand.

 

That's incredible! That's one of those things you couldn't ever imagine. Truth is stranger than fiction!

 

Like everyone else says, I would try the boat pushing, as is, with minimal investment of time and money to see if it would even be close to what you need. Put some knees and cleats or whatever is needed, get the engine running properly, if the cutlass is serviceable, let it be, make sure water is dripping on the shaft seal/compression fitting and have a stand by tug in case it's not going to work or to assist in a tricky situation. Then you will see a lot better what needs to be done and if it's worth it.

 

I'm a tug captain, not an architect. I have seen numerous rudders with end plates on top and bottom of blade, this is first I've seen in the middle. end plates keep the water from leaving at the tips, improving efficiency.
There is old captains, and bold captains, but no old bold captains!
I suggest some precautions to be safe.
For quick and easy power and control enhancement, add two outboard motors to your tugs stern, not quite at the corners. Brackets for motors to clamp on are quick to weld on and quick to wash off later. if they steer, fine, if not steerable, not a problem. Steer with engine thrust. Ahead on one, reverse on other.
You probably have some motors already.
In your attempt to test moving the 40ft barge, I'd try it with just the diesel at first, but if I was getting into trouble, I'd quickly fire up those outboards.
A yawl boat (assist skiff) with outboard motor, hipped up alongside the bow, either side, can aid dramatically in steering control, by working ahead or astern as needed, if for example, the wind caught you. Communications important, as yawl boat operator is under command of tug skipper.
Good luck!

Horn signals might be easier heard over the racket than walkie-talkies.
Traditional signals are:
One toot means ahead. One toot means stop (if already under power).
Two toots always means back, go astern.
Three toots means check (slow down)
Four toots means strong (more power).
derived from old bell signals , bridge to engineer in engineroom.

 

Hello Again,

Thank you so much for all the help.

We are starting work next week and another question has popped up. We are going to install push knee, dry exhaust etc and do some repair where they had stainless tabs screwed on and there is heavy corrosion behind .

Does any one have any leads on how to determine what type of aluminum plate was used in the hull? I understand there are many different types.

Given that the vessel is a 1975 we are worried that it might have different composition than todays plate.

I called Sea Ark but they said they have no idea where the records went for those Mon Ark.

 

Fleeting services on the Mississippi river, use small tugs with single screw 671 GM, working in river current.
They build and strip tows and shift the separated barges to their proper fleets (by customer and cargo). These are 200 ft long 40 ft wide rectangular barges drawing 10 ft fully loaded.
You aren't moving anything that big, so I think you'll be just fine.

After installing your tow knees, you need an arrangement for face wires, leading from stern corners of barge to stern corners of tug. There is a lot of stress on these fittings, so padeyes or cleats need lots of reinforcement in the deck they are attached to.
Full time push boats have face wire winches on the stern. You could use some steamboat ratchets (big bottle screws with a built in ratchet handle in middle) instead of winches to tighten up the face wires. They need to be TIGHT to have control.

Here is a photo of a steamboat ratchet and another of a small twin screw tug showing the face wires clearly. Her winches are on the bow and the wires fairleaded up the side decks. Awkward arrangement. Unkind to the wires. Won't last long in those sharp bends.

 

If you're going to do that, this boat wasn't necessarily built for those type stresses so Id watch for signs of buckling like this...

 

The Monark hull is well built and has an excellent reputation.
I would not expect the hull to buckle like that pop can.
But if stress is not sufficiently distributed over enough deck area, the deck could peel up or deform. Failure in the deck where wires attached would occur LONG before hull buckled.
Without face wires, you can't push and steer, maintain control.

 

More questions on converting the workboat

Hello All,

I am sorry with all the questions.....sadly there will be many more.

And again I appreciate all the help.

corrosion - When mixing different metals with the aluminum does it only matter below the waters surface?
THe back of hull has two small spots that are heavily corroded under the trims tabs that we removed. It has always been a freshwater vessel.
Once I repair these can someone specifiy what type of annodes to use and where to install these

Paint - Can anyone specify what type of paint is best to use above water and below the water. I have no idea what is on it now. Flat red colour on bottom. The rest is white. Also entire deck has black non slip on it that is mostly gone. Black rubbery type with sand in it.

marine exhaust wrap I am installing dry stacks now to get rid of the raw water cooled exhaust. We operate until freeze up and we don't want to worry about draining each night. I will need a large quantity for the engine room

Propellor It currently has a 24 by 24 RH propeller on and 1.5 inch shaft. I know this is marginal. But to large a project to change this year. There is a 3 1/4" clearance to the top of the tunnel. Should I be trying to find a flatter propeller? With a slightly larger diameter. Say a 26" by 18" or 20". I know nothing about propeller dynamics. But given that was a planning vessel before I would think this has too much pitch on it.

 

Aluminum expands and contracts with temperature changes, much more than steel.
Vinyl or rubber based elastic marine paint is appropriate. Many paint companies offer these products. Here is one, as example. http://www.simcocoatings.com/mopaint.html

Simflex-427 Aluminum Boat Paint
A single part vinyl resin and zinc chromate based coating which exhibits excellent adhesion to aluminum and galvanized substrates. Used as a primer/finish coat directly applied over raw aluminum saving considerable cost.
Product Data Sheet Product Data Sheet

Simflex-117 Vinyl Pretreatment Wash Primer
A two-component, quick-dry etch primer designed for use on aluminum, galvanized steel, and ferrous substrates to ensure good adhesion of subsequent primer coats. Confirms to MIL-P-15328, Navy formula #117.

Silkyd-7210 High Performance Silicone Modifed Alkyd Paint
A high grade, air-dry, VOC compliant, copolymerised silicone alkyd enamel. The ultimate non-chalking finish coat. Tough, resilient coating designed for exceptional exterior durability with superior gloss and color retention. It is an ideal maintenance topcoat with good flexibility and intercoat adhesion.
Product Data Sheet Product Data Sheet (PDF Format)

Decks should be light colored so not to be burning hot in summer, even through shoe soles. On some ships, I made extra large sandals to wear over my regular shoes, because the dark gray deck was blistering hot.
Topsides on aluminum boats are best left natural and unpainted. Quickly forms a dull gray oxide finish that's very hard. Workboats get scratched and scarred, and scratched up paint is less attractive than NO paint.

Bottom antifouling is area specific. What are other boats using on the lake, that works well?
Recommend AVOID using cayenne pepper paints. While the capsicum does work, you won't find anyone willing to grind or sand it off later, when next ready to repaint. That red pepper sanding dust will eat you up!

 

How is the engine cooled?