Mainship 390 wiring trunk

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rgano

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FROLIC
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Mainship 30 Pilot II since 2015. GB-42 1986-2015. Former Unlimited Tonnage Master
Has anybody with a 390 or other Mainship models with the wiring trunk just aft of the starboard side cabin door opened it up?

Not my boat. Asking for a friend.
 
Yes. To get at the wires and cables you take out the helm window. I don’t see any other way and that's what I did.

To get the window out took heat gun (not too hot) and about 30 wood shims pushed under the window frame to get the sealant to release.


—Kevin
 
Yes. To get at the wires and cables you take out the helm window. I don’t see any other way and that's what I did.

To get the window out took heat gun (not too hot) and about 30 wood shims pushed under the window frame to get the sealant to release.

—Kevin
May I ask why either you or rgano's friend need to get into this wiring trunk? I ask because I noticed a 390 for sale and am trying to learn about it. If this is a need that almost nobody else will ever have, then that's probably OK, but if you needed to go through this amount of invasive grief for something more routine, like just to maybe run a cable for an antenna or radar set or something, then I would question the overall design sense of the boat.
 
Not sure its exactly a design flaw. Could the wiring runs and cables be easier to maintain? Probably. Was it awful, no.

I needed to get the shift cable replaced and the window needed to come out to do it. Then needed to install nmea2000 net cable. Easier to do with window out. Then stbd running light ground wire.

Just about to seal the window up after all that . Will use butyl tape as it will be easier to remove if needed.

--Kevin
 
May I ask why either you or rgano's friend need to get into this wiring trunk? I ask because I noticed a 390 for sale and am trying to learn about it. If this is a need that almost nobody else will ever have, then that's probably OK, but if you needed to go through this amount of invasive grief for something more routine, like just to maybe run a cable for an antenna or radar set or something, then I would question the overall design sense of the boat.

Well, having owned one for many years, I can say that I would not be shocked at all by any need to rip stuff apart to access components. Mainship gave zero Fricks about access for maintenance or future component replacement. I’ve cursed their engineers many times, and only hope their hell is a purgatory wherein they must spend their time fixing Mainships. :banghead:
 
Well, having owned one for many years, I can say that I would not be shocked at all by any need to rip stuff apart to access components. Mainship gave zero Fricks about access for maintenance or future component replacement. I’ve cursed their engineers many times, and only hope their hell is a purgatory wherein they must spend their time fixing Mainships. :banghead:
Well, now that was pretty emphatic. But it is kind of what I was wondering about.
 
Well, now that was pretty emphatic. But it is kind of what I was wondering about.
Apologies if I was a bit blunt! I’m not sure if they are any better or worse than other production boats of the era. I just know that there were many items that needed repair over the years that were made much worse by a complete lack of foresight by Mainship engineers. So, would I own another one? Maybe. Only if it was the best boat I could find in my price range. (Which truly could be the case depending on what you’re looking for. That is why they remain popular in my opinion.) I would absolutely not own another one with twin diesels. Yes… redundancies are good, as are handling abilities. But squeezing two motors down there made not only working on them a royal PITA, but also impacted other systems and your ability to access. I would make sure I got a top notch survey. While it is solid core FRP below waterline, the boat is balsa core with plywood in areas with fixtures. Like any boat of this construction, water intrusion can eventually lead to rotting core. Known problem areas are the step well adjacent to the lower helm door, as well as bridge deck. People will cite that the Cat 3116 motor is bad… but it is NOT. there was an early series run of those motors with a problem, but most were repaired a couple decades ago. I’d be surprised if you could find one that hadn’t been addressed. Otherwise, they are a rugged motor with reasonable parts access/cost due to their prolific use in medium duty trucks.

I hope this helps.
 
A MS350 lover but I second Phyrcooler's comments. Had a leak in STBD fuel tank and spent a year trying to figure out what to do. Finally figured leak was at rear weld, found a very small area I could cut an inspection hole and luckily couold repair leak ( this is a whole other story). But no way you can remove tanks, boat built around them. Even the fuel gauge in Port tank is located so it cannot be removed when it went bad. Luckily a second inspection hole was available for a second working guage. Oh, you will need 6' long arms to reach the midship's bilge pump if it goes bad.

All that said, it's a boat. They (Mfr's) do things like that, all of them. I have a friend who has to remove his engine to remove the oil filter and it's only a 24' boat! Every boat is a compromise. The MS350/390 (it's our 7th Cold Duck) fits our requirements perfectly now. At times a 40' ketch, 45' Newport Trawler, 30' Willard, 70' Halmatic, 26' Daytona and others fit our requirements. Don't dismiss the MS, if it's a boat you will have those days wishing you could kill the builders LOL
 
Oh, the original issue. I was able to run multiple cables down that STBD run by cutting a 6" access hole in flybridge STBD seat compartment then ran cables outside the big hose that was pretty much full. I tried running down it and could get a cable pull thru but could not pull the cables. I did not remove the window. The access hole allowed me to get a cable pull all the way down without much problem. I left the hole open, but you can put a hatch access to be clean and proper.
 
Don't dismiss the MS, if it's a boat you will have those days wishing you could kill the builders LOL
I get it. My wife bought this house for the view before I knew her and gave not a thought to the house. I'm in the process of rebuilding it - including many things which either shouldn't need it or were code-illegal even at the time. I hope the builder never shows his face here or I might end up in trouble. Hmmm, maybe I shouldn't be on record as saying that even as a joke because I bet there are others who feel the same.
 
It isn’t just a problem with Mainship, most builders do the same sort of stuff. I have a Formula that is a pretty good builder but they did some things on my boat that I scratch my head asking what were they thinking. All boats are compromises so just accept it and do what needs to be done.
 
On my Mainship (cruiser style) the starboard engine fuel filter is a breeze to change, readily accessible from the center platform of the engine bay. The port engine fuel filter takes my skinny, long armed 14 year old son to reach the filter. Well, at least I hope he's still able. He could reach it last summer when he was 13. Now he's 14 and a little bigger, we'll see. Might have to hire a 50 lb spider monkey from the zoo to squeeze between the hull and the engine instead.

Who builds a boat that requires child-size workers for routine maintenance? I might be (half) joking, but I really do avoid working in the engine bay when I'm alone on the boat. There are some tasks that are so difficult to reach that I only do them when my wife is at the boat with me, because if I get stuck and can't get out, I don't want to survive by drinking bilge water until somebody finds me a few days later.
 
Cold duck
could you send me a pick of the access hole on your starboard side bench you put in. I'm rerouting my mast cabling to a radar arch and removing the mast.
Cheers J.T
 
To J T Kearney, I'll try to get that picture today. Just got back from a convention. I'ts pretty simple, just in the floor aligned roughly with where the cables go down by the Stbd window. It allows you to put a cable pull thru the large hole below the instrument console and catch it at the hole, then you can put the cable pull thru the hole in the side bench and send it down by the window to the instrument console in the salon. I had to run a couple antenna wires and cable for a remote for the auto pilot, some 110vac lines to put AC at the flybridge, etc. I wanted AC outlets on the bridge for phone chargers etc. Anyway, there's no way I could get all those cables thru the rubber hose that most of the cables are run from the factory.
 
Access port to replace shifter cable

To J T Kearney, I'll try to get that picture today. Just got back from a convention. I'ts pretty simple, just in the floor aligned roughly with where the cables go down by the Stbd window. It allows you to put a cable pull thru the large hole below the instrument console and catch it at the hole, then you can put the cable pull thru the hole in the side bench and send it down by the window to the instrument console in the salon. I had to run a couple antenna wires and cable for a remote for the auto pilot, some 110vac lines to put AC at the flybridge, etc. I wanted AC outlets on the bridge for phone chargers etc. Anyway, there's no way I could get all those cables thru the rubber hose that most of the cables are run from the factory.


Cold Duck.


Purchased our 1998 Mainship 350 last July. Just back from the yard where I was told they couldn't replace upper helm shift cable without a lot of "destruction. Found your thread. I would be another who would very much appreciate a copy of the pic of that access port. Might well be the answer to my problem.
 
Cold Duck.


Purchased our 1998 Mainship 350 last July. Just back from the yard where I was told they couldn't replace upper helm shift cable without a lot of "destruction. Found your thread. I would be another who would very much appreciate a copy of the pic of that access port. Might well be the answer to my problem.

I just flew in from Hawaii last night. I can't find my old pics so will go down maybe today and take a picture. It's not a big deal, just in the stbd storage under the seat I cut a 6 or 8" dia hole so I could easily catch the end of the cable pull coming from the upper helm. Then have an easy shot at the window to get the cable pull down to the lower helm. This way I could get a cable pull from cable feed under the upper instrument panel to that hole, then I could easily run the cable pull down to the lower helm. I then installed small pull lines I leave going to the upper helm and the lower helm to pull new cables if needed. Without the hole, there's no way you can snake that cable pull and hit the spot by the window to get down to the lower helm. It's just a "relay" spot. As I said, you can put a hatch over the hole. I have just left mine open.
I haven't looked, but if the control cable goes thru the plastic tube with all the other cables, you cannot just tape the new cable and pull it thru. The cables in that tube are all crisscrossed and would make that pull almost impossible. If the control cable is outside that tube, you could probably duct tape the new cable to the old and pull it thru without putting in the relay hole. But with the "relay" hole it's easy to pull a new control cable down. It just won't be in the tube that is too crowed as it is.
 
Access port to replace shifter cable

Cold Duck,


Excellent information. Many thanks! I would still like the picture, but please don't make a special trip. The information you've provided is a very good road map.
 
Cold Duck,


Excellent information. Many thanks! I would still like the picture, but please don't make a special trip. The information you've provided is a very good road map.

OK, it's blowing 30+ expecting 50+ later this afternoon so going down to the boat is not looking great right now. Will probably get to it tomorrow. No matter what, should not require destructive process to get the job done :dance:
 
OK, it's blowing 30+ expecting 50+ later this afternoon so going down to the boat is not looking great right now. Will probably get to it tomorrow. No matter what, should not require destructive process to get the job done :dance:

Still crumy Weather but got these pics of the relay hole in the storage under the stbd seat on the flybridge.
 

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The pics are a great help. Many thanks!
BTW, did you get 50+? Our high down here was only 38.
 
cold duck
thanks for the pic's. so it looks like you accessed through the side of the compartment towards the bow and are able to reach your hand in the hole to guide the cables down the starboard side to the helm. I hope that's right?
Cheers J.T.
 
cold duck
thanks for the pic's. so it looks like you accessed through the side of the compartment towards the bow and are able to reach your hand in the hole to guide the cables down the starboard side to the helm. I hope that's right?
Cheers J.T.

Exactly. I used one of those big hole cutters from Harbor Freight. Easy run with a cable puller from helm station to the hole then from the hole down to the lower helm. Still a little tricky getting down the window but a little trial and error will get it done.

We only registered 38kts here but was cold and rainy so walking down to the dock and trying to get on the fly bridge just wasn't appealing LOL!:socool:
 
Mainship 350 transmission engage/disengage problem

Thought my problem was a bad upper helm cable. Further diagnostic steps (before cutting the cable pull port recommended by Cold Duck - still a very good solution to that problem!) has eliminated the cables as the issue. Problem of engaging or disengaging the transmission is worsening. Upper helm unusable for maneuvering. Lower helm getting worse. ZF transmission. Had the heat exchanger replaced right after purchasing Journey in July 2023. Problem first noticed about three months later. Any ideas on what is causing this? Any "simple" checks or fixes? Or am I headed back to the yard?
 
Take the cables off the upper control and see if it works freely. Then the lower one. My upper control shift side broke, due to what I thought was a bad cable. Once i got the cables off I found it needed greasing.

--Kevin

P.s- label the cables as you remove them.
 
Take the cables off the upper control and see if it works freely. Then the lower one. My upper control shift side broke, due to what I thought was a bad cable. Once i got the cables off I found it needed greasing.

--Kevin

P.s- label the cables as you remove them.

Agreed. You may disconnect cables at tranny and make sure they are fully engaging the trans. If you are lucky it might just be cable adjustment, a broken or sticky cable. I assume you have checked oil level in the trans. Worse case the tranny has internal issues. Removing the ZF is a bear, hope you don't have to remove it.
 
Thanks to all of you for the suggestions. For anyone interested in the result (which we hope is as "permanent" as anything on a boat!), the process went as follows. Cable disconnected at the upper helm (UH) - lever shifted smoothly. Reconnected cable at UH and disconnected it at lower helm (LH) - UH lever shifted smoothly. With cable from UH to LH still disconnected from the lower helm, LH lever still binding into and out of neutral, but workable. Disconnected cable from LH at transmission shift arm. Binding went away. Manually moved the shift arm. Moveable but difficult. WD 40 where the lever arm shaft enters the housing and on the pivot shift above it. MUCH smoother. Reattached disconnected cables. Both helm shifters working smoothly! UH station back "on line." Thanks again for the suggestions and the support!
 

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