Need advise on engine removal from Mainship 430

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Waterant

Senior Member
Joined
Oct 3, 2018
Messages
269
Location
Canada
Vessel Name
DORA
Vessel Make
2002 Mainship 430
Hi guys,

has anyone removed an engine from Mainship 430?

Marina people here have no idea how to do this.
removing the door and cover gives me 29" of horizontal clearance and the engine mounts are 28" so that fit straight back, but because the engine is not in the middle, the door opening is too small for a boom to go on an angle :banghead:

also, it seems like there is not enough height for the engine and hoist under the boom to clear the opening vertically.

If you have done this before, I'd appreciate some advice and pictures.

Thank you
 
Although one inch of spare space is not a lot to work with it is do-able. Sounds like you will have to life the engine using a scaffold or some type of arch over the engine to lift it and then drag or swing it forward to more closely match the door opening.

Unless it is a "V" configured engine (V-8, V-4) it really should fit out the door.

good luck

pete
 
yes, it fits the door opening just fine with a couple of inches to spare. I'm trying to imagine the scaffold thingy which has to be built to raise 1000lb engine and if it the saloon floor will be able to hold it.

i was hopping someone did that specifically in Mainship 430 or a similar aft cabin boat where are not a lot of space to pock with a crane boom inside the cabinet
 
Some people buy the Frame and trolley kits and a chain hoist from Harbor Freight or similar to get it to the door.

With strong backs and or pads under the frame legs, most decks will hold fine unless yours is rotting.
 
I have done in but in a different boat.

We used a hydraulic boom crane with the boat in the water. We attached chain-hoists to the end of the boom and avoided A-frames, etc.

Our door was not centered either and, furthermore, we had two engine to drop-in, one on each side. But with the boat in the water we could move it sideways and angle it to get the engines in through the back door and over the openings.

The vertical clearance was very tight in our case but it just made it!

What engine are you installing? Maybe you can disassemble something to get the vertical clearance. In our case we only had to remove the air filter.

Here is a video of the starboard engine going in:

https://youtu.be/1ydei5ggv1A
 
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On our last boat I pulled the engines out of the engine room but left them in the salon, 1 each year, then I stacked it above the other engine. I made a crane out of a 6x6” I beam. I reinforced the deck with some 2bys under the deck down to the stringers. We picked the engine up with a chain fall on a trolley. Slid it over and set it down on some dummy stringers on the deck. Took about 2 hours to do an engine. In your situation I would do the same thing to get it out of the engine room. Then set the engine on something like furniture dollies and roll it out the door. You may have to build a deck that is flat to roll it out the door. Then crane it off the boat. On the port side I made a support out of 6x6s. One vertical with a horizontal one below it on the deck. On the starboard side I used 2x2 metal tube since there was a cabinet there and I couldn’t fit in the 6x6 wood timber. I included some photos of it so you could visualize what it looked like.
 

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super. Thank you for the suggestions and the picture.

The engine is Yanmar 6LYA-STP and i already remove everything except the block, head and transmission. i did remove the head a well to check the condition of the cylinders but had to put it back because there is no easy way to hook the engine to the crane without the brackets on the head.
 
super. Thank you for the suggestions and the picture.
The engine is Yanmar 6LYA-STP and i already remove everything except the block, head and transmission. i did remove the head a well to check the condition of the cylinders but had to put it back because there is no easy way to hook the engine to the crane without the brackets on the head.

A welding shop can fabricate 2 brackets that you can mount to the block using head bolt holes. So you can remove the head reducing weight by 150 lbs or so and reducing height in the process.

I would recommend removing transmission as well as it a simple job and reduces weight and length.
 
Don't rule out the possibility of drilling a 1" hole in the saloon overhead and having the crane outside the boat -- or use chain come-alongs to a Travelift front beam -- or build an H frame outside with legs going down to the side decks -- long beams F&A to spread the load.


Once it's hanging in the saloon, use a platform of maybe 4x4s to help the saloon deck take the load as you roll it out the back. You might put some supports from the deck down to the longitudinals in the engine room to help keep the deck in the right place.



When you're done, put a small round hatch inside and out to seal the hole.


Jim
 
That's an aft cabin boat, like ours. Even after the engine is up to the level of the salon floor it still has to go up about 3 feet to get out the aft door. Probably need a fork lift with a real long fork. I hope to never have to do this.
 
Heck any decent bolt hole like where the alternator bolts to and the bellhousing can be used to lift the block so you can remove the head and tranny lessen up the weight. Put the bolt through a chain link with a good washer. Do it all the time on land with a cherry picker.
 
I always enjoy looking at some quality work like Comodave showed of his lifting scaffold.
Might be a bit of overkill but better safe than sorry. That rig can probably hold twice or three times the weight of your engine.

pete
 
My boat is also aft cabin, engines are under the saloon floor, like yours. The door is opposite the aft hatch opening above the engines. I was on the hard, had a HIAB truck do the lifting. My door is 27", my engines, with the HEs removed, are 26 3/4", so I had room for only a layer of cardboard to protect the door frame. The HIAB guy had done this before, so for him, it was easy. I had to remove the trans from the near engine, to get the angle right, but the further away engine had enough swinging room to come up with the trans attached. Start to finish, about 2 hours, two coming out, 2 others going in.
 
I always enjoy looking at some quality work like Comodave showed of his lifting scaffold.
Might be a bit of overkill but better safe than sorry. That rig can probably hold twice or three times the weight of your engine.

pete

My wife says I always overdo it…. But I would rather overdo it than underdo it.
 
Removing transmission would help a lot but I do not see how to do this without lifting the engine from the engine mounts because rear mounts are on the transmission and forward are on the engine and the engine will have to move forward to slide off the transmission.

Making a hole in the cabin ceiling for the crane from above may work to lift the engine up but does not help to get it out of the rear hatch.

One possible solution we are considering is to

- Keep the boat in the water and have a long boom coming in to the rear hatch from land.

- Use the lines to rotate the boat to position the crane end above the engine

- Raise the engine with hoist and put it on the 4x4 frame on the cabin floor with support beams under the floor to the hull stringers.

- Disconnect the hoist from the engine and the crane boom

- Lower the boom to the engine and strap the engine directly to the boom with some heavy duty straps to fit into the 40" vertical clearance of the hatch

But this strapping the engine to the boom part looks questionable to me.


The only other option I see is raising the engine to the cabin floor with the scuffles, setting it on the engine stand and disassembling it to smaller pieces. At which point I can probably just rebuild right in the saloon and put it back :)
 
Maybe add some photos of the cabin so we can see what you are working with.
 
Do you know how to remove the upper sliding door to make a bigger opening? It gives you a lot more room to work with.
 
> Do you know how to remove the upper sliding door to make a bigger opening? It gives you a lot more room to work with.

29" is when the door and door cover are removed. There is no way to make it wider more without cutting furniture and the hull


> Maybe add some photos of the cabin so we can see what you are working with.

Good idea. I attached here.
* I apologize for the mess. It's a work in progress :blush:
 

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Probably a little late now, but we bought a few hydraulic press rigs from Harbor Freight and used then with a beam across for our A frames. Cheap and afterwards I had a press for everybody who helped removed the engine!:banghead:
 
Probably a little late now, but we bought a few hydraulic press rigs from Harbor Freight and used then with a beam across for our A frames. Cheap and afterwards I had a press for everybody who helped removed the engine!:banghead:

Not late at all. we are still contemplating the plan.
Is this the press you've got?
https://www.harborfreight.com/12-ton-shop-press-33497.html

do you have any pictures?
did you use the frames of those presses as the vertical support for a beam for a hoist in the middle?
this is a great idea. will be much cheaper and faster than fabricating those supports from scratch.
thank you.
 
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Yes, that's the press. Easy to assemble and handle. In my application, I used them to raise a 1350hp MTU that weighed 4000lbs. But I only had to lift one end then blocked it so we could get the 600lb crank out. Had to drill a hole in the salon floor. Using a single press frame, it was about all it could take, around 2000lbs, but it did the job. If I were lifting a single engine, I think i would use 4, two in front, two in back and use 3 beams so I could center over the engine to get balance. You might be able to get by with 2 frames and a single beam. I just don't know your configuration.
 
You might be able to get by with 2 frames and a single beam. I just don't know your configuration.

i think 2 on each side of the saloon with the beam on top will be enough to raise my 1000Lb engine and move it to the middle of the door opening.
I will have to reinforce the floor under those.
I think the pieces of this puzzle are starting to get to their places now.
 
One possible solution we are considering is to

- Keep the boat in the water and have a long boom coming in to the rear hatch from land.

I watched our previous yard do exactly that on the same model boat as our previous. Boat was stern to the bulkhead wall where their TraveLift well lived.

Cummins tech removed most (all?) of the bolt-ons first (heat exchanger, aftercooler, etc) and he told me that gave them about a half inch clearance on either side of the aft doorway. Don't know, or remember, about the gear...

Do sorta remember it only took them something like 30 minutes with the boom truck.

-Chris
 
it only took them something like 30 minutes with the boom truck.

Thanks, Chris. It's great to have a yard that has some experience.
Unfortunately, my marina did not do anything like that before and does not have a boom truck.

If anyone knows an experienced boom truck operator in Washington D.C. / Virginia area, send me the contact, please.
 
Don't know what happened but I did reply that those are the hydraulic press frames I used. Don't have pictures. I used the frames as you suggest, with a beam to get hoist aligned with engine for balance. The frames go together easy, don't take up much room. I lifted (sp?) 2000 lbs with one frame which was at the limit of the frames but 1000lbs with 2 frames no issues.
 
There is another method I have used and that's a beam thru the windows and then a beam across the engine. My Willard set up fine for that configuration but that was only a Perkins 4-109 50 hp
 
I did it in Mainship 43 3SR. Engine needed removal and braced floor of salon, the put A frame on it, hoisted engine up onto I-beam trolley, rolled it back towards removed sliding door, stuck boom of fork truck in then plucked engine out. Repeat in reverse.
 
Roll out on deck
 

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