Swim platform question 350/390 Owners

[jclays]

Good morning
To the owners that removed the foam and water from your swim platform. Was there a notable decrease in fuel consumption or a little increase in speed when you preformed this work? Mine has never been done and I am considering doing this on my next haul out. Expecting to pay at least 5k. Ouch. Mine is a 1997 350 Twin Volvos.
Thanks
Jim

 

[Cold Duck]

I have a 1997 Mainship 350 with a single CAT 3116. I have no idea if there's water in my swim step or not. Not sure how to determine it without opening it up. I have Faus teak covering the swim step so not easy to cut a hole in it to check. Boat sits in water same as my buddies 390 who has opened his up and is dry. Since he is a Yanmar very difficult to compare speeds, rpm etc. Be curious to see anything/experiences other 350/390 owners have on the subject.

 

[Comodave]

I would do it myself. Cut the top open for the hatches. Then use a drill with a long flexible extension with a drill bit on the end. Use the drill bit like a router to cut through the foam. It will cut through it very easily. You will have to clean up the edges with something like a putty knife once you are done with the drill. Much easier than paying $5K. I did a quick search for a drill extension and found this one on Amazon.

ENKAY - Heavy Duty Flex Shaft with 1/4 inch Keyless Chuck (56 inches)

 

[jclays]

I would do it myself. Cut the top open for the hatches. Then use a drill with a long flexible extension with a drill bit on the end. Use the drill bit like a router to cut through the foam. It will cut through it very easily. You will have to clean up the edges with something like a putty knife once you are done with the drill. Much easier than paying $5K. I did a quick search for a drill extension and found this one on Amazon.

ENKAY - Heavy Duty Flex Shaft with 1/4 inch Keyless Chuck (56 inches)

The So. Cal the marina I am at will not allow that type of work to be performed.
There are only 2 DIY shipyards in South California. One charges 180 to haul out and power wash, 180 to block, and 210 a day.
The second one charges 2,000 per month with a 2,000 deposit. All material such as paints, epoxies, fillers and caulking must be bought thru their store.
EPA writes theses yards up and fines them heavily. They have staff that just keeps the grounds cleaned up.
Not worth the hassle. Cant even do your own bottom paint around here unless you have a small enough boat to trailer home and hope your neighbor doesnt call in on you.

 

[Gdavid]

The So. Cal the marina I am at will not allow that type of work to be performed.
There are only 2 DIY shipyards in South California. One charges 180 to haul out and power wash, 180 to block, and 210 a day.
The second one charges 2,000 per month with a 2,000 deposit. All material such as paints, epoxies, fillers and caulking must be bought thru their store.
EPA writes theses yards up and fines them heavily. They have staff that just keeps the grounds cleaned up.
Not worth the hassle. Cant even do your own bottom paint around here unless you have a small enough boat to trailer home and hope your neighbor doesnt call in on you.

I don't see why the boat would need to be hauled to do the work. Get a couple of hatches, mark up the cutout templates with a sharpie and go anchor out and cut them out and install your hatches. Then it is a straightforward but painstaking process of digging out the foam. Many boats have had this mod done and could give you the measurements to install the hatches in order to access each side. With a shop vac, drill and jig saw you could install the hatches without making a mess.

 

[Comodave]

Yes, I use the drill with the extended bit and a shop vac sucking up the debris. It will be time consuming but not too difficult technically. We had a foam filled boat and I had to add some cleats. Cut access plate holes and went to work with the drill chewing up the foam. It was a PITA but doable. That is what I love about the boatyards here, I can do whatever I want except sanding bottom paint.

 

[Delta Riverat]

Yeah, go ahead and drill a "test hole"

Not going to be any louder than a vacuum or an electric pressure washer.

 

[Bacchus]

Yeah, go ahead and drill a "test hole"

Not going to be any louder than a vacuum or an electric pressure washer.

In fact run the vac while drilling and everyone will just hear the vac.
Plus you showed concern for others by not creating and dust / dirt that is blowing around.

 

[jclays]

Anyone with the answer to my original question.
I know how to do the work. Just not able to where the boats at. Thanks though.

 

[Cold Duck]

Anyone with the answer to my original question.
I know how to do the work. Just not able to where the boats at. Thanks though.

Agreed, we really need 350/390 owners or past owners with their experiences to give us a hand here.

 

[Cartouche]

Anyone with the answer to my original question.
I know how to do the work. Just not able to where the boats at. Thanks though.

I did it on our 390 and cannot say I noticed a difference but did liked not carrying the 1000lbs of water I removed. to the poster who said his buddy's platform is dry, he probably took of the inspection cover and saw the top skin of fiberglass and made the assumption it was dry. break through the red skin and you will find the surprise. cheers

 

[jclays]

I did it on our 390 and cannot say I noticed a difference but did liked not carrying the 1000lbs of water I removed. to the poster who said his buddy's platform is dry, he probably took of the inspection cover and saw the top skin of fiberglass and made the assumption it was dry. break through the red skin and you will find the surprise. cheers

Thanks for your input.

 

[Comodave]

I did it on our 390 and cannot say I noticed a difference but did liked not carrying the 1000lbs of water I removed. to the poster who said his buddy's platform is dry, he probably took of the inspection cover and saw the top skin of fiberglass and made the assumption it was dry. break through the red skin and you will find the surprise. cheers

If there was that much weight in the swim platform then it would certainly make a pretty big difference. Particularly with it being so far aft.

 

[jclays]

Was the foam supporting the lid of the swim platform?
Were supports of any kind installed to replace the support provided by the foam?
Thanks

 

[Cartouche]

Was the foam supporting the lid of the swim platform?
Were supports of any kind installed to replace the support provided by the foam?
Thanks

No the foam offers no support the lid is sitting on the platform, and secured under the rub rail