Trimaran - Especially Searunner - Owners

[rossad]

Hi Aquavitae
I put a new strut bearing in my 37 ft trimaran. It was standard made for a 1 inch shaft.
Fixing all the problems of vibration. I had to use a puller to get the prop off.
The cutless bearing fitted neatly into the strut by tapping it in with a block of wood.
engine alignment is a tricky job.

[Roy M]

aquavitae, I also have a one inch shaft on my 40, it's 17 feet long and supported at each frame (with the exception of the coupling and shaft log) with pillar block bearings. Alignment is merely bringing the engine coupling plate so that it sits flat against the shaft coupling plate. Flat means that there is a maximum 0.004" gap at one corner of the mating faces of the couplings. You achieve this by slacking the engine coupling bolts, measuring how much gap there is between the two plates, then moving the engine around on the engine bed until the two couplings are within the 4 mil range (and that the bolts line up as they ought, of course). This is achieved by lifting or lowering the four corners of the engine resting on the bed, using the engine mount threads to raise or lower as needed. If the axis of the engine is not the same as the coupling, you need to shift the forward end of the engine port or starboard. This is done by loosening the attachment of the engine mounts to the bed, placing a two foot 2X4 between the bed and the engine, and prying the engine. You may have to take some load off by raising the engine a bit. The base of the engine mount has two holes. The single hole is aft, the elongated hole is forward, for all the mounts. This allows you to shift the axis port and starboard. It's a pain to get it right, but it is absolutely worth the trouble. My engine, with its super-long shaft, runs with no vibration, to speak of. That means, a cup of coffee, sitting on the sterncastle table, doesn't dance around. At most, you get little concentric waves forming when the shaft is turning at speed. Here are some pics to give you some perspective. The first few pics are the template I built to get the engine mounts aligned correctly, then setting the engine down onto the mounts, how I take the weight off the engine for fine adjustments, and how the coupling plates look when aligned. I used my halyard to bring the engine aboard.:

[blewett_john]

I sure wish my bilges were that pretty. Perhaps someday once all the structural repairs are done.

My 37 with a Volvo Model 2003 28hp diesel has a 1.25" bronze shaft. The beauty of my setup is that the strut unbolts so replacing the cutlass bearing only requires removing the prop, unbolting the strut, sliding it off, and then replacing the cutlass bearing in the shop at home.

[Cadence]

Ditto on grats on the bilge!

[aquavitae]

Thanks, guys

I have a Yanmar 3GM30 with a 1-inch propeller shaft (about 6 feet long), the engine is centrally mounted under the aft cockpit steps. Where the prop shaft exits the boat is a stern tube over which the PSS (packless shaft seal) slides, with the forward end of the PSS over the prop shaft. PSS part numbers are quite explicit in requesting the shaft log size to the nearest 1/8 inch )for example (shaft log to be from 2&1/4 "to 2&3/8" )- any larger or smaller and you are into a different model.

The seal is leaking under way and needs to be replaced at haul out. I have to go to another country (BVI) to haul out at the excellent Nanny Cay marina on Tortola. I would slide it off and measure but with the boat in the water, I fear I may not be able to get it back on. Any idea what size it should be?
Is each boat different ?

This looks like a job I can do myself. Replacing the cutless bearing (without pulling the shaft) and re-aligning the engine will likely be hired out to boatyard machinist.

[Roy M]

I, too, have the 3GM30F on my 40. Mine is located under the port, aft bilge of the cockpit, up against the centerboard trunk. I am confused, though, with your issue. The shaft log (PSS) is leaking and needs replacement? This is a great opportunity to install a conventional shaft log. That's all I have used for, approaching, forty years. All of the pack less units I have worked on were failures. The other question is that of the cutlass bearing, that fits in the external shaft strut. A boatyard can easily pop yours out and replace it.

[Roy M]

Status report on WILDERNESS: I got the sand applied on the starboard side nonskid yesterday. Long day. This morning the dew had settled heavily overnight and I used the shop vac to remove the excess sand (and water) to great effect. Everything cured perfectly. Tomorrow I will apply two coats of LPU (Sterling Moon Dust) atop the cleaned nonskid, then a final topcoat after I am completely finished, so the colors will be perfectly matched. Apparently, Sterling is going out of business. West Marine is no longer stocking it, I bought three half gallons of brushing catalyst to complete my cabin, cockpit and dodger painting, and I had to get it from another vendor at a very large price because it's hard to find now. At least this is the last time I will probably have to paint. If I survive long enough to need to do it again, I'll use another brand.

Our weather in San Diego is becoming iffy, but I should be able to get all of the painting and nonskid done before the heavy (?) rains arrive in January. Then, I'll either start building the dodger, under cover, or get back to finishing the interior, especially the galley. When the winter wanes, I'll pull the stick and overhaul it. People are starting to talk about my leaving the dock for an extended period, but I remind them that the end tie is not going to be permanently available. I see my slip fees as a "condo payment" so I can return at any time to the greatest homeport in the world.

[blewett_john]

Originally Posted by Roy M

Status report on WILDERNESS:

Our weather in San Diego is becoming iffy

Oh, poor you. I bet it is not 26 degrees, rainy/snowy. You should try getting paint to dry in that.

Just kidding. I still want to see pictures of your progress. Sounds like things are moving right along.

[OzTriGuy]

Can anyone help me with this cheap 27ft trimaran - http://www.gumtree.com.au/s-ad/sarat...ts-/1065060864


Sent from my iPhone using Cruisers Sailing Forum

[sctpc]

Originally Posted by OzTriGuy

Can anyone help me with this cheap 27ft trimaran - http://www.gumtree.com.au/s-ad/sarat...ts-/1065060864

Sent from my iPhone using Cruisers Sailing Forum

You could log on to Seabreeze and ask a lot of those guys live in Sydney. I would if it was Melbourne

[Cavalier MK2]

That is a Hedley Nicol based design. If 27 feet it was based on the 25' Nicol Clipper design. The next jump up was the 29' Islander but it had more headroom etc.....There is a long thread on Nicols on boatdesign.net. The Clippers sail well if not overloaded.

[Roy M]

Hi blewett_john! Just messing with you. We had a couple days of rain, heavy enough to wash the decks clean, and a great forecast for the next week to ten days. So, onward to painting the port side and sterncastle decks, finishing some of the little dinghy ramp details, and starting to put stuff back on the boat, besides paint and sand. There's not much to see right now, other than lots of chaos, but soon I'll have something to crow about. This dinghy roller project turned out to be a far more complex one than I had expected, but the return on the investment will be well worth it. For my needs, having a RIB and a somewhat powerful outboard makes so many things possible. This project has made it a reality, being able to launch and retrieve the dink singlehanded, with very little effort and in a minute or so. It's like the boat was intended for this accessory. I'm especially happy how the propane tank chocks are working out. Two of the 33 pound composite tanks will live under the outboard tube of the RIB, with one more in the boat. All within the footprint of the RIB itself. I have not had a chance to really play with the dink, so I can't estimate the total range that 100 pounds of propane will give me, but I suspect it will be sizeable.

[sassarassa]

Hi all,

It has taken a while but I finally had a chance to organise all my pics from the last 2 years.

So thought you may be interested in the progress pics of my 10 weeks on the hard in 2012 ... with all that sanding I almost grew some shoulders

https://www.facebook.com/media/set/?...1&l=eca82640b8

Highlights

1. Engine room tidy up (no where near as neat as yours Roy but still a big improvement)
2. Sand blast and repaint the engine beds
3. New 2nd hand 3GM30F
4. All new bearings along the prop shaft ... interesting that there was actually no cutlass bearing in the stern tube?? PSS shaft seal
5. outer decks stripped back to glass and all soft spots removed and re-glassed
6. Wooden ama hatches replaced with custom Cule hatches. Same for front hatch
7. Below waterline sanded back to undercoat. Antifoul was up to 10mm thick in places!
8. Above waterline, topsides, coach house sides and cockpit stripped faired and painted with 2 pack Jotun
9. All Stainless hardware on rudder replaced/rebuilt and new chainplates (apart from forestay chainplates buried in the deck)
10. RIB deck cradle glassed into the aft deck a'la Mark's design

Still heaps to do but while I sit in the marina dreaming of the next trip she looks pretty and gives me warm fuzzy feelings every time I look at her

Big thanks to everyone who contributes to this thread as it has helped me so much and continues to do so.

cheers

Jon

[sassarassa]

Originally Posted by aquavitae

Thanks, guys

I have a Yanmar 3GM30 with a 1-inch propeller shaft (about 6 feet long), the engine is centrally mounted under the aft cockpit steps. Where the prop shaft exits the boat is a stern tube over which the PSS (packless shaft seal) slides, with the forward end of the PSS over the prop shaft. PSS part numbers are quite explicit in requesting the shaft log size to the nearest 1/8 inch )for example (shaft log to be from 2&1/4 "to 2&3/8" )- any larger or smaller and you are into a different model.

The seal is leaking under way and needs to be replaced at haul out. .

:Aquavitea - how much use has the PSS shaft seal had? If it doesn't leak when stopped it sounds like the seal is ok. So could just be the usual bedding in process for these seals or it could need more tension on the spring.

Mine made a fine spray mist while underway when I first installed it. I loosened the grub screws in the anchor collar, slide it up a little (compressing the spring), retightened the grub screws and this combined with use resulted in no leaks at all, ever. It been 2 years now.

NB: This pic was before I connected the water cooling hose. Would have definitely leaked without doing this

https://www.facebook.com/photo.php?f...1&l=bb4e43cbed

cheers,

Jon

[blewett_john]

Originally Posted by sassarassa

Hi all,


So thought you may be interested in the progress pics of my 10 weeks on the hard in 2012 ... with all that sanding I almost grew some shoulders

Still heaps to do but while I sit in the marina dreaming of the next trip she looks pretty and gives me warm fuzzy feelings every time I look at her

Big thanks to everyone who contributes to this thread as it has helped me so much and continues to do so.

cheers

Jon

Jon,

Beautiful!! I can only hope my boat will look that good when it is done.

I have a question for you: My wife is worried that the cockpit has no sun protection. Your cockpit cover looks absolutely elegant. Could you post more pictures of the details of its design?

Great job on the rework of your boat.