Mainship 34MK1 Modification Qestions

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R. Bush

Veteran Member
Joined
Nov 12, 2019
Messages
72
Location
Canada
Vessel Name
TBIDO
Vessel Make
Island Gypsy 32
After two years of searching I have finally made an offer on a 1979 Mainship 34. There are a couple of things I am wondering about.

The first is the engine. The good news is that it has been repowered by the previous * 2 owner and has pretty low hours. My only concern is that the original 160 hp Perkins was replace by a 320 hp detroit Diesel 8.2L. I have no desire to burn a lot of fuel going fast, but am I going to do any harm to the engine by essentially idling it along at 6 knots for hours on end?

My second concern is that I am not as spry as I used to be and it is a LONG way up from the dock to the side deck and then a LONG step down into the cockpit. I was wondering if anyone else has added a stern access door to these boats? I was looking at a Prairie a couple of days ago and it seemed much more civilized in this respect. Just step off of the dock onto the swim platform and then walk aboard thru the stern access door. The marina where the boat is currently located has a good fiberglass shop and I was considering asking them to add a door once I take delivery. Any reason I shouldn't do it?

Thanks; as always; for the informed advice.
 
Ralph, can't specifically talk about the Mainship, but I think the layout is not too different from the CHB (Clipper) 34 I had, and I absolutely recommend having a stern door installed. Choose the side of the transom that will be nearest the dock when berthed in the best position. The pilot door side usually being that. In our case the starboard side.
Here's a pic of mine. Not al that challenging for a boatyard.
 

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We had a 40' main ship for 5 years and did a bit of research into just this idea. It's doable, but additional strength is needed around the door as it does add some strength.

There's a guy in Belize that made a "tailgate" transom (full width!) and uses his boat hard for charters and diving. I bet you could get away with a little door without too much trouble
 
To get from the cockpit to the side decks, the mark 1 relied on the removable steps, two wooden treads mounted on a metal frame that attached just below the gunnel on each side. They aren't the most sustantial steps for sure, especially for less sure footed boaters but they do the job. The mark 2 and mark 3 had a lower gunnel height around the cockpit. I have long legs for my height and am younger than the average trawler owner but it is a bit awkward for me. On the other hand, the high gunnels are very secure at containing children and pets. I am still on the fence about a cockpit door, will probably install one because we have large dogs to load and unload onto the dinghy.
 
I am still on the fence about a cockpit door, will probably install one because we have large dogs to load and unload onto the dinghy.

I too have a large and aging dog and a 95 year old father-in-law that need to be loaded onto the boat. I'm going to use them as my excuse for the upgrade and if that happens to make my life easier too; then so much the better!
 
Option #1: Sit on the gunnel and swing one leg over at a time.

OPtion #2: Install a small 1 or 2 step steps on the dock and a fold down step on the inside of the gunnel.

Going the route of installing a transom door is going to be a very, very expensive third option. Consider the cost and whether that is better invested in a boat that has one already.
 
Going the route of installing a transom door is going to be a very, very expensive third option. Consider the cost and whether that is better invested in a boat that has one already.

The marina where the boat is currently sitting has a good fibreglass shop. I am going to ask them for an estimate so I will know what my options are. I will post the number here in case anyone is interested.
 
I've respectfully given my opinion on why I wouldn't add a cockpit door to our 34 when the question was posed in the past. Yes, it sure would be nice to walk right into the cockpit from the swim platform and vice-versa but I wouldn't do it to our boat. I really feel that removing a section of the gunwale would affect the athwartship strength of the hull. As I believe I mentioned if a previous post, maybe if the bulkheads under the cockpit and in the engine compartment were reinforced with gussets glassed to the hull sides and existing stringers, the hull would be stiffened enough where cutting a chunk of the gunwale out would be ok.
As mentioned ,there have been a few that own a 34 where the modification has been done. I think one might be a member on here where the boat was bought with a cockpit access that was already done. It was cut into the port side of the hull. I would try to get in contact with an owner of the modified boats and ask them if they have any issues, specifically increased hull "working" in a beam sea.
 
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There are some 34s that have had a transom gate added. It is certainly doable IF you add enough reinforcement to the transom. Just make sure that the yard doing the work is knowledgeable enough on how to do it. Then have them add about 50% more reinforcement and you should be good. Have fun with it and good luck.
 
One pretty bit difference between the Mark 1 versus the 2 and 3 is the flybridge supports that are supported by the gunnels, not only does this load the gunnel but they also come down at an angle which is pushing outward on the gunnel. I still believe it can be done with adequate reinforcement but it is a consideration.

I've done a lot of fiberglass work in the past for personal as well as professional settings and would not be sinking the money into paying someone else to do the work. I'm actually even considering a classic tuna door approach that provides an opening but leaves the gunnel intact. Less useful for people but would work fine for dogs.
 
I actually HAD the same concerns, but this has been done so many times now with no reported issues that if I was going to do it to a MKI I would not think twice about it.

I get all the engineering and stress concerns, but the reality from those that have "been there and done it" is that the concerns become unfounded after the fact.

The link I gave to the Trawler Forum is a guy that opened the transom WAY up, then drove the boat to Belize from Florida and now does daily resort dive trips, still running and hasn't broken yet
 
I agree - we had absolutely no issues whatsoever with the transom door, but boy was it handy. Not only for people, often loaded down with provisions, but anyone with physical issues particularly. It also made boarding from the swim-step and dinghy so easy as well. You can see in the pic in my post #2 above, that the telescopic swimming ladder mounted under the swim-step was just outside it as well. It made coming in out of the water very simple.

There is no way I would have bought a boat one had to swing legs over or add a separate ladder to get into it. We did for a short time have a boat like that, a Cuddles (Resort) 35, Mk 1. You had to do as someone described - sit on the capping, and swing the legs in.

Made it a less than comfortable process for anyone, and getting my father, (in with bilateral hip replacements), was a nightmare. I noted all later models had a transom door from build, and many of our model had had one added.

Most of the stiffening strength of the hull is, after all, from the unbroken and continuous cockpit deck, not the gun'ls.
 
I had a 34 M1 and agree with the difficulty entering and exiting the cockpit. It's easy to see why they stepped down the freeboard aft on later models.

I think an opening in the transom can be done without much concern for the integrity of the boat. Whether it's feasible or easy to get on and off the boat from the dock via the swim platform will depend on the situation. I'm not sure I'd count on that as the primary way to get on and off the boat from the dock. I thought about putting an opening in my boat to get to the dinghy more easily, but never considered it for dockside access.

My current boat has a deeper cockpit and higher freeboard than the 34 and I have two small portable steps, one for the dock and one for the cockpit. If you're in a permanent slip you can usually have steps permanently mounted there. This may be a simpler solution to meet your requirement for easier entry/exit.

Congratulations BTW. These are good boats. Where is the one you've settled on?20210805_000040.jpg
 
There's a lot of back and forth about how to run a DD engine, load percents, and so on. That said:

You "should" be fine running it at lower RPMs for long periods of time, as long as the engine maintains a good operational temperature. I run dual DD 671's at low speeds more often than not, but tend to crack them up a bit once a day before the end of a long outing. Typically, mine will very lightly smoke for a few seconds as they burn off anything residual and settle back into the clear again.

I'd look around at the different forums and search your specific engine to get the most information you can in the subject, before taking anyone's statements to heart as truth.

There's a LOT of arguments around this. Be warned.
 
I've often thought about cutting the transom to install a door on Lady Sue, 1982 Mainship I, and if my wife traveled along very often I probably would've done it. Instead I bought a boarding handle (Whitecap-mfr) that fits securely into the fishpole holder on the starboard side near the boarding ladders. It's like a railing to hold while climbing the outboard steps to the gunnel, then down the inboard steps to the cockpit deck. I put my free hand on the cockpit overhang as I descend from the gunnel. Sounds complicated but isn't. Discount houses sell them for less than catalog $240.00

Jim Ferry
 
Congratulations BTW. These are good boats. Where is the one you've settled on?View attachment 119863

Thank you everyone for all of the replies.

The boat I was looking at is in Penetanguishene, ON on the Georgian Bay. Unfortunately for me the surveyor got about half way thru the survey and said "I wouldn't buy this boat!". That is twice in a row for me now. I'm beginning to think that I really don't have a clue and should take up gardening. Sad to say, but it is starting to look like the end of the boating season is heaving into view up here in the great frozen North. Maybe I should just bag it for this season and hope that the market cools off and the prices stabilize for next year.
 
Sorry to hear about your efforts on Mainship. I thinking of selling Lady Sue next spring. At 87 my wife and doctor have been at me. She is a well kept, yard maintained boat I bought in 1989. She suffered through Sandy with a lot of cosmetic damage: pulpit, swim platform, railings, hull gouges but the insurance money was sufficient to get her in shape. The Perkins is fine. I tossed the genny years ago because I never anchor out and the damned 3K Onan was noisier than the Perkins. If you are interested, I'll send some photos and information. Price is not main concern. She is insured for $26K.
Jim Ferry sue46jim@gmail.com
 
You dodged a bullet - the 8.2 Detroit was a terrible design.
 
Sad to say, but it is starting to look like the end of the boating season is heaving into view up here in the great frozen North. Maybe I should just bag it for this season and hope that the market cools off and the prices stabilize for next year.

Don't conflate boating season and buying season. Often fall is the best time to be shopping. Settle in and be prepared to act when the right boat appears.
 
After two years of searching I have finally made an offer on a 1979 Mainship 34. There are a couple of things I am wondering about.

The first is the engine. The good news is that it has been repowered by the previous * 2 owner and has pretty low hours. My only concern is that the original 160 hp Perkins was replace by a 320 hp detroit Diesel 8.2L.


I see your surveyor's advice is to walk, but just wanted to add a comment...

320 HP and DD 8.2 in the same sentence seems a bit odd. As does 8.2L instead of 8.2T.

I remember our Mk III had a DD 8.2T, at either 210- or 220 HP... as Silverton (Mainship) began installing those later in both the Silverton 34 Convertible (a pair) and in the Mainship Mk III (a single)... and it was well matched to the Mainship.

There have been reported issues, but we never had any problems with ours. Easy 7 kt cruise, 9-10 kts easily OK but more fuel expenditure than necessary, 14 kts flogging it (IIRC).

-Chris
 
stern door

Just got done doing a pass thru on our newly purchased 79' MKI. Just lift the pass thru up and step through. Integrity of the transom stays intact.
 

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