Ski Boat Transom Replacement

[79XLT]

I have an iboard ski boat - 1986 Malibu Skier - that the transom is soft around all the swim platform attachment bolts where they go through the transom, and the inner layer of fiberglass is loose as well in same locations on the inside of the boat. What I was wondering is if anyone has done this type of transom, and what you would recommend for replacement material. I can see the upper and side edges of the inside of the transom. It looks like to me it would be an easy replacement. Any advice/help would be greatly appreciated.

 

[system-f]

Re: Ski Boat Transom Replacement

I don't think these boats have much of a transom. I have heard horror stories about people losing their swim platforms while in the lake and read about them. Some of the newer ski boats just run the transom platform mounts into fiberglass only!!!!

The fix is fiberglass and plywood or some corrosion proof metal.

If it were my boat I would: (if your gas tank is in the rear you will have to remove it or anything else in the way)
1. clean up the areas that need the backing real good, down to clean glass
2. cut some 3/4 exterior or marine grade plywood as large as would fit in the area, if you can cover the entire transom even better.
3. Glass in the plywood using many layers of 1708 biax making sure to tab it into the sides and bottom of the hull where ever possible.
4. Use the largest possible stainless steel bolts and washers to attach the swim platform brackets through the plywood and glass and seal with 3m 4200.

Basically spread the load out. One of the guys I spoke with had this done to his Mastercraft after his platform fell off while in the lake. All it took was a 325lb guy to jump on the very edge.

In comparison my swim platform has handled a 375lb guy on the far edge, but my I/O boat has a much stronger transom.

 

[79XLT]

Re: Ski Boat Transom Replacement

You seem to be right about the transom. I guess because the motor doesn't push on it, they didn't think it had to be that strong. It probably wouldn't have taken much to pull the platform bolts right through, glad I caught it before it got that far. Forgive me, this is new to me, but I am not sure what you mean by tabbing to the sides and bottom of the hull. If I can picture it in my head, do you mean to extend the 1708 past the edges of the new wood to grab the sides and bottom? Do I need to remove the black paint (I'm guessing its bilge paint) for the stuff to adhere? Thank you for your reply and your help.

Oh, yeah - my swim platform was bolted on with 1/4 bolts - from the factory.