Swim Platform Bracket fasteners

Hello fellow CCFs!
I removed my swim platform and brackets to clean the teak, the brackets, and the back of the boat in general. The lags fastening the top of the brackets were 3/8"X 1" and the bottom screws were #10 x 1-1/4" long with tapered heads. Do these sound like the correct/original fasteners? I must also add that I suspect they may not be because after I removed the brackets, I discovered that each one had been raised about an inch at some point in the boats previous life to raise the platform for some reason. Should I use a longer lag bolt when going back together or stay with what I found installed previously? Thank you.

Here are some pictures to better show what I'm working with…

I agree that through hull bolts with backing plates would be the strongest method for heavy loads on the platform but how do you waterproof it? Or, is it even an issue since it looks like the lags are above the waterline? Another issue that comes to mind is where to get SS backing plates or would galvanized pieces from the hardware store be sufficient? I have the 3m 4200 white and plan on placing a moderate size perimeter bead and a couple middle ones on the bracket backs and some on the fasteners when re-assembling.

As you can see I also have some repairs to make before re-installing the brackets. My plan is to clean out and re-fill the old holes w/West Systems Six10 thickened Epoxy. The gelcoat cracks under and around the bracket areas will be repaired like I intend to repair the ones shown on the side of the boat. That is by forming a beveled groove with either a dremel or a V-shaped can opener, then filling w/evercoat polyester gel-paste and finishing. What I haven't decided on is what to fill the pictured areas on the back of the boat under the brackets where gelcoat used to be? Should I used the Six10 epoxy or the evercoat polyester gel-paste? The evercoat polyester gel-paste labeling says "GEL-PASTE SHOULD NOT BE APPLIED OVER EPOXY"? If I used the gel-paste on these areas wouldn't i be putting on top of epoxy (the brown areas)?

Thanks again Peter and to anyone else who replies!

I'm with Pete on the 4200 to be used as sealing the holes.

What is your plan with the paint? at the transom? at the sides? Are those gel cracks, or paint chips? I worry about the sides............

The platform holes would have been moved up if they were trying to find more solid wood in rotting stringers.... Or if the boat sits low in the rear and has wet foam (and rotting stringers), they may have raised the platform to get it out of the water. I saw an Excel that had it's platform raised almost 3 inches to get it out of the water! Very, very wet foam in that boat with very sad stringers. Check it out under the floor, in the stern and near the battery.

Thanks for checking Hollywood.

I worked on this most of this weekend. Most of the time was spent cleaning the paint, scale, and varnish/polyurethane off of the brackets. Good news is the through bolts are ROCK SOlID, thanks Peter. When it gets warmer I will disassemble and repair the holes and gelcoat under the brackets then go back together.

Thanks for the feedback Steve. Your comment about the embedded wood in the stern got me poking around and tapping with a hammer to check. When i poked in one hole it when clear through. There are 7 pieces of wood embedded in the stern of this 87 and 5 are solid 100%. The two pieces for the middle brackets next to the main stringers (not the boat lift piece) are 70% and will need repaired next winter. Fortunately there is enough material to get by for this season.

It appears that his 87 was left in the water every season and instead of cleaning the bottom of the hull they decided to paint it. I don't believe the bottom was repainted due to blisters. The the stringers and floor eventually rotted and the wet foam underneath froze and stress cracked the gelcoat. The stringers and floor have since been replaced. I'm going to repair all the gel cracks before putting in the water this season. Eventually I will either repaint or re-gel the boat.

   

Thank you. Mine wasn't difficult for the platform fastener modification because the tank vent, feed, and fill were still disconnected from the stringer job. The tank, brackets, and hardware were also previously cleaned and the tank emptied. This area of the boat however does seam to be a dirty one which can make the job more difficult, and without a tank drain and working with fuel in the tank would be more difficult. Also removing/disconnect the fuel fill hose I imagine is a bit tricky. I have to install a new fuel fill and hose when I go back together and plan on installing the hose on the tank first positioning and securing the tank in its proper place, then sliding the fill down through the deck and into the connecting hose and fastening the fill flange to the deck.