Thoughts on the Mainship 350/390?

[PNK]

I am hoping to get some thoughts from those of you who own Mainships, because my wife and I are going to look at a 350 tomorrow. ( It seems very similar to what is also called a 390.) It is a 1999 model.
From other threads you may have read that I have been looking for something in the 36' range, and hopefully a Monk, Island Gypsy or GB, but the pickings are slim to none these days, and those that come up seem to be sold before it is even possible to contact the broker, so we have broadened are search.
The one we will be looking at has a single CAT3206, which would not be my favorite, but I do prefer a single. It has about 4000 hours, the listing says it will cruise at around 8 knots, with consumption of around 1 gallon/nm, which seems high for this size and weight of boat with this size engine.
It has newer electronics and AGM's, canvas, etc.
Everyone on TF is always so helpful and knowledgeable, I am hoping to get some ideas about what to look for and what potential concerns are.
Thank you!

 

[Shrew]

The Mainship 350 Trawler was renamed to the 390 around 2000. There are subtle differences:

350 has a full berth in the guest, the 390 has a twins.

My 350 has aluminum rails, all the 390's I've seen has SS rails and a sampson post.

The upper counter on the port side Galley has dish storage that isn't present in the 350

galley Cabinets are flush mount on the 390, and surface mount raised panel on the 350.

350 has a small 'desk' in salon to stbd just inside of the slider that isn't present on the 390.

exterior cockpit hatches are locking in the 390.

--------------------------

Survey the engine. If it is has over 1,000 hrs it's more than likely safe. There were a number of 3206's that had 'soft block's' and were known to grenade around 500+ hours. Most of these are more than likely off of the market or have been repowered by now. Mine was repowered early on with a Yanmar. We suspect our model was one of them.

 

[PNK]

Shrew, you were dead right on every point, except for some reason the owner had added locking latches to the forward hatch.
I was wrong about the engine, it is a CAT3116, with 4200 hours; engine access was surprisingly easy, with a welded ladder. Interior was all carpeted, not sure if that is standard, but I imagine it helps to reduce noise and vibration. Not so great for spills though.
We are seriously thinking about making an offer, and would obviously do a survey, including engine and gen-set, but any thoughts about MS issues that don't always show up?( I am thinking about stuff like cored-hull moisture, like we had in a Legacy several years ago. Turned out not to be a big deal, but we weren't sure at first.)
Really appreciate your help!

 

[Iggy]

4200 hours, still new! I crew on a ferry with twin Cats with over 50,000 hours and still going strong.

 

[twistedtree]

I helped a couple on their first voyage in a Mainship from Portland Me to Beverly Ma a number of years ago. About an hour into the trip I realized that the bilge pump was running a lot and on investigation that we were taking on water somewhere in the stern. I figured out bailout points, then we kept on going. The pumps were managing the water, but if they failed, we would be in trouble. It later turned out that this was a known problem with this model of flooding in the swim platform, and subsequent intrusion into the laz. Perhaps others can speak to the model and vintage to watch for. I don’t recall.

Aside from that specific issue, my take on that boat and others I have been on is that they are very light weight builds. That’s not good or bad. It’s just what it is, and your intended use should match. They are one of the more affordable boats for their size, and for loop and light cruising can be an excellent choice.

 

[Unclematt]

There was a fix for the swim platform water intrusion which I believe included a bilge pump. I had an offer on one a few years back. It failed the survey for a number of reasons. The 2 negatives I found were with all the e glass up it blew around like a kite even in light air. I also found the bow thruster had trouble overcoming the breeze making it a challenge backing into a slip. There was a lot I liked about them. In the end I decided it was not my kind of boat.

 

[Keysdisease]

The leaking transom extension/swim platform technically a "bustle" is a well known issue and there was indeed a factory "fix" around 2002.

Basically if your swim platform has a hatch in it some type "fix" has most probably been done. These were addressed various ways, remove the top of the platform and remove all the waterlogged foam. From there various "fixes," some with bilge pumps, some with connections to the main hull. Almost all involved some type hatch in the platform.

I would be surprised if there are still any of these boats around where this has not been addressed

I found this, which fairly well describes the issue.

The Swim Platform Repair Page

 

[garmstro55]

I have the next generation after the 390 (MS400) but I can say, in general, Mainship is a quality boat for the money. It is not going to compete with Hatteras or Viking but the workmanship is decent and they have a lot of nice features for a mid-range boat.

Something to check on, or make sure the surveyor does, is softness in the upper deck and/or the deck at the bottom of the steps. They didn't do a great job of sealing the screw and other penetrations and if water seeped in you likely have some rot going on. This can be an expensive repair unless you have the skills to DIY.

The late David Pascoe reviewed the 350 and, somewhat surprisingly, he kind of liked it. I say "surprisingly" because he was usually pretty critical of "production" boats. Here is a link: https://www.yachtsurvey.com/boatreviews/mainship_350_trawler.htm

The survey should tell the tale as to whether the boat has been properly maintained and if there are any "no-go" issues but if an economical trawler is what you are after, and the layout and design are appealing to you, you should be happy with a Mainship. I don't see many owners complaining about them.

If you look in the library here on the forum, I had uploaded a comparison of the 350/390 and the 400, which will give you some additional specs on the model you are looking at.

By the way, I suspect the 1 gallon/hour might be inaccurate, I think it would be higher but I'll let others who have this model comment.

If it surveys well and the price is right, I say go for it!

Best of luck.

 

[JustCruisin]

I looked at a few 390's when I was shopping...There is a lot to like about them. However, the ones I saw had not been well maintained. One 390 I looked at had obvious hull issues from a cracked and leaking plastic thru hull...it was on the hard and when I asked the owner, who said he was getting ready to launch the boat what he intended to do about it he said nothing....it's a used boat. I passed on that one, plus it had twin Volvos....If I had found one well maintained without structural issues I may have bought one. As with any boat, it is only as good as it has been maintained. Good survey is a must. I would not be afraid of the Cat if it checks out ok...just be prepared to maintain it if you want to keep it reliable. Non-turbo engines are cheaper and easier to maintain. Slim pickin's out there right now. I really like the MS400...they are/were out of my budget. Might be my next boat though...best of luck!

 

[Unclematt]

I was looking for a Loop boat and had looked at one 350 and three 390's. All but one were low hours with very worn interiors telling me they almost never left the marina. The last one was a 390 which looked very nice. The survey showed hidden hull damage amidships from going against a wall in a storm. It looked perfect but about 8 feet were soft. The auto pilot pump was under the flybridge dash and was annoyingly loud. It had gauges not working and old electronics. The engine was my first choice of Yanmar with about 3K hours which purred. The engine survey showed it had not been maintained by someone that knew what they were doing. The oil sample came back with high metal readings w/ water present. The cutlass bearing was shot, seal was leaking and may have had a bent shaft. The genset also did not run and was rusted from water spraying from the shaft seal. I learned a lot from that experience. I had to fly in for the survey and sea trial, two nights in a motel, rental car, then two very good surveyors and a short haul. Cost 5K and I walked. I hind site I would have done the same thing again. I enjoyed the journey and the valued lesson. Then I bought a boat I fell in love with and I have no regrets.

 

[Shrew]

Shrew, you were dead right on every point, except for some reason the owner had added locking latches to the forward hatch.
I was wrong about the engine, it is a CAT3116, with 4200 hours; engine access was surprisingly easy, with a welded ladder. Interior was all carpeted, not sure if that is standard, but I imagine it helps to reduce noise and vibration. Not so great for spills though.
We are seriously thinking about making an offer, and would obviously do a survey, including engine and gen-set, but any thoughts about MS issues that don't always show up?( I am thinking about stuff like cored-hull moisture, like we had in a Legacy several years ago. Turned out not to be a big deal, but we weren't sure at first.)
Really appreciate your help!

I meant 3116's as well. If this is 4200 hrs, its NOT one of those engines.

 

[Capt Ray]

2000 ms 390

We picked up our MS 390, built in Aug 2000, in East Greenwich RI in June 2020. Brought it to the south shore of Long Is NY for the rest of that season. Then pushed off on The Great Loop in May 2021. It has aluminum rails, we added a few extra hand holds so my wife who has MS can traverse all over this boat without her cane. We thought we had purchased something "special"... but once we started the loop we see another Mainship, most commonly a 390, most every week someplace. I now know a dozen+ other MS 350/390 owners after doing 70% of the Loop. We love ours. Our swim platform had not been properly fixed by either of the two previous owners. We found a fellow who had done two others before this one, and paid to have that done. Under $5K.

We'll finish our Loop in a couple months and keep going to Maine then follow the seasons up and down the coast, maybe do the Loop again. We have a single 3126 CAT, and cruise around 7-9.5K. Fuel consumption is HALF if we can keep it to 7K. About 2.5 nmpg at that speed. We just had the 2000 hour service performed while wintering here in FL.

Our 9HP bow thruster is enough in our experience, even in moderate wind. Early magazine articles indicate the earlier MS 350 models may have had under-powered bow thrusters. It is not likely, but if we ever had to replace ours, we'd go with 24vdc or put the battery up forward for this system. (The voltage drop when using it is a bit extreme IMO.)

There are a LOT of improvements that we describe peppered among our many blog posts for the past couple of years. http://shellerina.com e.g. You might check out our custom davit system, and did some upgrades to the galley this past month. A fully enclosed fly bridge is very nice, and is used ALL the time.

 

[mncruiser]

We purchased our 2001 390 last May in Michigan. Got lucky and found a freshwater only one, also very well maintained.

The 1nmpg fuel consumption is unrealistic. I have a single Yanmar 300, have flo scans and I think I’m right around 1.8-2.4 around 8kts. Others are correct, try to run 8.5 or higher, watch that fuel meter jump to 7 or 8.

We are Great Lakes weekend boaters for now with 2 small kids, sometimes we are in more of a hurry sometimes so push it. The boat will do 11-12 kts, but it is a violent affair, pushes the biggest wake you’ve ever seen. High cruise for us is 10 to 10.5 kts.

We love the boat all around. Got very lucky and found a very well maintained one.

If the sanitation lines have not been replaced, plan on doing that. It’s a big job as the factory secured things very well. I did it myself and saved a bunch of $, with a lot of help from advice here.

They are not a top of the line boat, but I feel decent quality and able to be easily worked on and upgraded. I would not want twins for the poor engine access with that setup.

Our thruster works great, my goal this next season is not to use it as much and master single screw piloting.

In our area there aren’t many, we are a popular boat because it’s the boat all the sailors want when they are sick of flapping sails and living in a windowless tomb! We are also on the younger side of the crowd, I skipped about 4-5 boats and just bought ahead a few boats. Don’t regret it at all. I generally identify well with the slower going crew, and you more mature friends make better cocktails and conversations anyway!

I’d love to answer more questions to help you out.

Best,

mncruiser

 

[Shrew]

Nautical Mile per gallon is not a completely reasonable measurement. Gallon per hour is more accurate, and more widely used to calculate overall burn rate. NMPG is variable and influenced by tide, current, and wind. GPH is static, relative to RPM.

 

[Gdavid]

Nautical Mile per gallon is not a completely reasonable measurement. Gallon per hour is more accurate, and more widely used to calculate overall burn rate. NMPG is variable and influenced by tide, current, and wind. GPH is static, relative to RPM.

I respectfully disagree, gallon per hour is equally impacted by those variables so it doesn't make any more accurate. You can figure out your best nautical mile per gallon and apply correction facts to it just as easily and simplify your trip planning.

 

[slowgoesit]

Nautical Mile per gallon is not a completely reasonable measurement. Gallon per hour is more accurate, and more widely used to calculate overall burn rate. NMPG is variable and influenced by tide, current, and wind. GPH is static, relative to RPM.

Shrew, I agree with the following caveat. Unless you know what SPEED you are obtaining with that GPH, the GPH number in and of itself is not very helpful!

 

[Phyrcooler]

In my mind they are kind of the Chevy of the fleet. Overall hullform design is decent. Quality of construction about 7.5/10. Definitely production line boats, but maybe a scootch better than the 90’s “Taiwanese trawlers”. Downsides: Very poor design engineering coordination when it comes to systems. Frankly Mainship didn’t give two fricks about access for maintenance or future repairs of items you know will need to be tended to some day. Much cursing of lazy Mainship designers ensued over what should have been simple repairs on mine. Not deal killers. Just occasional absolutely unnecessary frustrations had a little design effort been made. Ignore discussions regarding twins vs singles. You’re not crossing oceans, and if you maintain your boat, it’s fuel and fuel systems, the chance of an engine failure is almost nonexistent. You don’t want to deal with the access headaches of maintenance and repairs on twin engines squeezed into that space. (Mine had twin Yanmars).

It’s not all negative. They are a reasonably priced, (well… nothing is reasonable these days! ) seaworthy, costal or loop cruisers. Just know that many are showing their age - being 20(+) years old. Inspect carefully - especially for soft decks that start to show up in older boats. Especially the upper deck. They are balsa cored like most vessels of that era. The Cat 3116 motor was used in fleets of medium duty trucks that are still around. Parts are available. The early production run motors that had issues should have long been vetted out. Best of luck to you.

 

[captkev]

1999 ms 350

I have owned a 350 for 8 years now, third owner of the vessel. She is rock solid and very seaworthy been out in 45kt winds and 10+ ft seas. The boat handled it much better that the crew. I have twin VP200's and would not trade them for anything. As others have said, get a survey. The Swim platform issue has likely been repaired, mine was when I purchased the boat. I did have a soft spot on the swim platform deck, improperly sealed hatch from the repair. I removed the deck one fall, brought it home and completely removed the core from the bottom. Replace the core and glassed the bottom side adding a solid glass shoulder around the hatch opening. No other issues with the hull/decks she was just surveyed again for insurance (moved to FL). One difference missed in the 350/390 delta. The 350 has the bolt on swim trunk as mentioned, the 390's was glassed in as part of the hull mfg process. Not a big deal, but a difference. IMO most of the single screw boats are under powered. I like to cruise at 9.5, "fast" cruise at 13 and WOT 16.5. Very economical at 9.5, at little less at 13 and thirsty at 16.5. We are currently looking at downsizing to a 30ft Pilot RR. If you are interested PM me.

 

[mncruiser]

They are balsa cored like most vessels of that era

To confirm, the hulls are *NOT* cored on the Mainship models of this era. Some of the decking and superstructure may be, but the hull is solid fiberglass.

 

[Cartouche]

To confirm, the hulls are *NOT* cored on the Mainship models of this era. Some of the decking and superstructure may be, but the hull is solid fiberglass.

The decks most certainly are cored every part of them except around the Sampson post

 

[Phyrcooler]

To confirm, the hulls are *NOT* cored on the Mainship models of this era. Some of the decking and superstructure may be, but the hull is solid fiberglass.

You are partially correct. I specifically was referring to the decks - which absolutely are. However, to further clarify, the hull above the waterline *is* cored as I discovered when replacing a couple of vent and drain through-hulls.

 

[Shrew]

You are partially correct. I specifically was referring to the decks - which absolutely are. However, to further clarify, the hull above the waterline *is* cored as I discovered when replacing a couple of vent and drain through-hulls.

Agreed. Balsa on the hull above the waterline and the decks.

Take a careful look at the windlass. Whether it was the factory or the dealer who installed it on mine, they simply cut a hole and installed the windlass. They caulked the exterior of the windlass, but did nothing with the hole that the rode passes through.

The balsa sandwiched between the deck and the inner was like wet paper bags.

 

[captkev]

Correct, I removed the deck, not the trunk. flipped the deck over and cut the underside of the deck out. Replaced all the old core and wooden supports, glassed over everything.

 

[jclays]

I have a 1997/350. Twin Volvo turbo 200hp. Ive had her for 2 years. Very solid boat. Very capable for coastal cruising. Purchased her in San Francisco and brought her to Long Beach Ca. Ran into some very rough water around Pt. Conception and she held her own just fine. She will rock though. Do not be afraid of twins or Volvos. Volvos are good engines. I have the TAMD 41 p-a engines with 765 hours. Price of parts are comparable to other make engines within a reasonable difference +or-. My swim platform has never been touched that I can tell. No hatches anywhere. I eventually probe around to check for water intrusion. I suspect there might be only because its a known issue. I cruise her between 9-10knts. Wot is 16.8knts.

 

[jclays]

Correct, I removed the deck, not the trunk. flipped the deck over and cut the underside of the deck out. Replaced all the old core and wooden supports, glassed over everything.

How hard was it to remove the platform top? I have a 1997/350 that I believe has never been touched. There are no hatches on the top of the platform.

 

[Cartouche]

How hard was it to remove the platform top? I have a 1997/350 that I believe has never been touched. There are no hatches on the top of the platform.

Its not that bad we did it 2 years ago to remove foam and install a stern thruster. take stainless trim off at the joint you will the expose a very narly joint thjat has screws coming from the top and the bottom, remove all screws and then heat silicone joint and pry apart. there is a fiberglass skin over the 3 compartments which is easy to break through and then the foam I guarantee will be waterlogged, I think we removed about 750# of water from the platform. I installed 2 Hatches that allow for great storage when all is put back together and also allows you to remove water that comes back into the platform some say from the trim tabs, could be from where the lines go through the box to the tabs. some install a bilge pump (this was mainships fix)

 

[jclays]

Its not that bad we did it 2 years ago to remove foam and install a stern thruster. take stainless trim off at the joint you will the expose a very narly joint thjat has screws coming from the top and the bottom, remove all screws and then heat silicone joint and pry apart. there is a fiberglass skin over the 3 compartments which is easy to break through and then the foam I guarantee will be waterlogged, I think we removed about 750# of water from the platform. I installed 2 Hatches that allow for great storage when all is put back together and also allows you to remove water that comes back into the platform some say from the trim tabs, could be from where the lines go through the box to the tabs. some install a bilge pump (this was mainships fix)

Good info.
How thick is the platform cover?
Once the foam is removed will additional support have to be added to replace the support if any the foam provided?
Along with the soggy foam was there standing water inside the compartment?
Thanks
Jim

 

[Cartouche]

Good info.
How thick is the platform cover?
Once the foam is removed will additional support have to be added to replace the support if any the foam provided?
Along with the soggy foam was there standing water inside the compartment?
Thanks
Jim

Yes standing water up here in the north the foam would freeze and thaw as it is titally water logged the foam offers no support to the top. it is 3 compartments that the deck sits on. no extra support needed.

 

[Cartouche]

Good info.
How thick is the platform cover?
Once the foam is removed will additional support have to be added to replace the support if any the foam provided?
Along with the soggy foam was there standing water inside the compartment?
Thanks
Jim

you can see by pictures in post 23 it is not that thick fiberglass both sides with a balsa sandwich in the middle I forgot one step when you remove stainless trim - there are then screws holding rub rail in - take a picture of location you remove them as there are a bunch of possibilities in the rub rail, then you will see narly joint. project well worth doing. It also helps with List issues

 

[jclays]

Check your mail.