View Full Version : Re-Mounting Swim Platform

06-15-2010, 03:37 PM
I have been polishing, polishing and polishing the new boat. Really looking good.

Had a little movement in the platform, not much. The bolts look like they had been replaced. So I pulled it off. I found that the previous owner had reattached it using metal concrete anchors. At least he sealed it well and did it only on the top two bolts on each bracket. Pulled the gas tank and drilled the inside of the anchors so I could pull them out. Wood looked good. The back of the anchors were visible just slightly above the floor. I am going to through bolt the top two, lag the bottom ones and through bolt the mid support. Just don't feel like cutting the floor at this time. I did see another poster do this and it seem like it worked well.


The top holes that the anchors were in are probably about 5/8". I was going to try to use 3/8" bolts that will need to be placed at the top of the holes. I was thinking of epoxying the holes solid and then re-drilling. Then I thought this may be a bad idea if when I tighten everything up the epoxy slug will bottom out or bust loose and prevent good compression. So I was then thinking of just filling the holes and sealing everything up with 5200.

Any suggestions, Thanks!!

06-16-2010, 10:48 AM
If the holes are 5/8", why not use 5/8" bolts?

I think you will be fine with the lag bolts on the bottom assuming the wood is in good shape.

You should be able to fill those holes with epoxy . Be sure they are planner with the surrounding surfaces so that the load is transferred outside the slug. That said, it it a challenge to put that much epoxy on a vertical surface unless you are laying up glass which is a more involved process (requires tapering the holes to a larger size).

I would probably go with the sealant option as well. Just use a large fender washer on the inside so the load is applied to the existing structure.

06-16-2010, 10:48 AM
I would go with some bigger bolts I just can get a nut and washer on the backside without cutting the floor up. Too close to the floor. I have backing plates made for the inside.

I would like to epoxy the and then redrill however I may just seal it all up. Regradless the epoxy or sealant is just acting as a filler.

I am also considering making a larger backing / adapter plate out of 1/2" aluminum maybe 5" x 6" mouting that to the outside of the transom and then bolting the existing brackets to that.

06-22-2010, 06:13 AM
in my 80 i can get to all of them withtout messging witht he floor . Floor stops fuel tank

06-23-2010, 10:53 AM
Back plate top two bolts only...

05-21-2013, 01:05 PM
NV.... this is a great help. I will remove the fuel tank today and see what I have to work with. Many thanks!

05-21-2013, 01:54 PM
You're welcome...Please post pictures of your work, everyone really enjoys the pics on this board.

05-22-2013, 04:38 PM
Don't half-a$$ed do the job. Cut the floor and put in thru-bolts..... getting new bolts is only half the resolution. The other half is getting a new seal on all four bolts. If you do two, you leave two lag bolts to continue to leak. You'll see what I mean when you get the lag screws out and tilt the boat up in the front. Typically, water will drain out of a water-soaked foam floor. Do all four bolts and seal it properly.... Your mileage may vary. Just sharing my experiences.

I did this a while back..... No big deal....

Use caution when removing the brackets from the gel.... otherwise it's straight forward.

Remove the fuel cell, cut the floor, use stainless hardware and thru-bolts, cover the hole(s) in the floor and use epoxy resin to set the cover back in place. Done deal...

If you haven't removed the fuel cell yet, order a new filler hose (cheap) and cut the old one out. It will save you a lot of headache trying to remove the old and hardened hose. Been there many times...



05-23-2013, 09:36 AM
I respectfully disagree with “cloaked”. You will achieve a good seal if you fill the bottom, and top holes with 3m 5200 before you install the bottom lag and top bolts.

05-23-2013, 07:02 PM
I respectfully disagree with “cloaked”. You will achieve a good seal if you fill the bottom, and top holes with 3m 5200 before you install the bottom lag and top bolts.
Duly and respectfully noted.... I just prefer to take it all out and do a full restoration. It's really easy to do and is almost as difficult while trying to work around the abbreviated repair...

What one doesn't get is the threaded connection of the lower lag bolts. At this point, it's all pretty much shot anyway.... Too bad MC did not do this connection in a better manner to begin.... Quality at its finest... :rolleyes: