View Full Version : **oj/mc Folding Swim Platform Bracket Install**

09-17-2007, 09:43 AM
Finally finished the install this weekend and let me tell you this is the single best improvement I have made to the boat and probably the cheapest!

Most have seen the pictures of the new brackets on the 08 models and there are few threads floating around if you want to do a search. Basically the brackets allow you to fold the platform instead of removing the platform for storage. The platform stays attached to the back of the boat and just hangs vertically from the transom.

Since I keep my boat in the garage and it fits much better without the platform off and since I go to the lake just about every weekend these brackets made perfect sense.

If you don't already know you can purchase the brackets from Mike at www.mymastercraft.com. I ordered mine on Monday and they were on my doorstep the same week. Mike is an avid supporter of this board and consistently provides us all with excellent service, tech support, and great prices! Thanks Mike!

Anyway on to the install. This particular install was on my 05 PS209. I assume it will be the same for all later models of PS/X series boats. I am sure other members will chime in regarding retrofitting other models.

Here is what the brackets looked like out of the box.

09-17-2007, 09:44 AM
Another picture...

09-17-2007, 09:45 AM
Top side pic

09-17-2007, 09:47 AM

09-17-2007, 09:49 AM
Ok first things first - Removing the factory brackets. My boat and just about every other pre08 boat came with slide in brackets which look something like these.

09-17-2007, 10:01 AM
On my boat they attached to the transom through six bolts. Two 1/4 bolts and one 3/8 ubolt which go up through the bottom of the transom and two 1/4 bolts which go through the horizontal part of the transom. The top two are through bolted with nuts and washers on the back side. The bottom two are threaded into the 1/4 plate in the transom.

Here is a pic.

09-17-2007, 10:02 AM
You have to take out the trunk liner and rear panel in the rear storage to reach the nuts on the top side of the upper bolts/ubolts. Take out all the factory bolts and remove the factory brackets. Mine were stuck to the transom pretty good with silicone so I had to slide in one of the swim platform mounts I had removed earlier from the teak deck and lean into it pretty good.

Once the factory brackets are removed here is what you are left with.

09-17-2007, 10:06 AM
After taking a few measurements I realized the new brackets would have to be pushed all the way up into the pockets for the platform to be close to the original height. I say close because even with the new brackets up as far as they can go my platform is going to sit about 1/2" closer to the water. Since my platform was already a couple inches above the water it's really not big deal.

Here is a pic of a test fit.

09-17-2007, 10:15 AM
None of the holes in the new bracket will line up with the existing holes in the transom. I thought about building an adapter bracket but realized it was not necessary and with Mike's guidance drilled 4 new holes.

The top two are through drilled 5/16 and are through bolted with nuts and washers on the back side. The lower tow mounting holes extend down past the inner liner of the boat and are located in the foam filled void between the hull and liner. Since there was no access to the back side of the lower two mount bolts they were drilled out to 17/64 and tapped for a 5/16 bolt.

FYI - There is an L shaped 1/4 piece of plate which is laminated in the hull to provide support for the brackets. It is this 1/4 plate which was drilled and tapped for the lower holes. All four new holes are securely fastened to or through this 1/4 piece of plate.

Here is a pic of the 4 new holes as well as the preexisting holes from the factory brackets.

09-17-2007, 10:17 AM
Carefully tapping the lower two holes to 5/16.

09-17-2007, 10:18 AM
The finished product cleaned up and ready for the new brackets.

09-17-2007, 10:29 AM
Once I made a dry fit run to make sure everything would line up. I had to use a countersink bit to bore our the taper on the holes in the OJ mounting brackets. It's funny the holes are 5/16 but the taper is for 1/4 bolt. :confused:

Once every thing looked good I broke out the 3M 5200 for a final install of the new brackets. I ran a very small bead all the way around the outside of the bracket as well as around/in each mounting hole. I also filled in the unused horizontal holes from the original brackets which will be covered up by the new bracket.

For the 4 vertical holes from the original brackets I used 1/4 stainless carriage bolts on two of the holes and simply reused the factory ubolt sans bracket for the other two holes. I sealed all four of them up really good with the 5200.

Here is a pic of the bracket mounted and torqued.

09-17-2007, 10:30 AM
Another shot...................

09-17-2007, 10:32 AM
Different angle...........

09-17-2007, 10:36 AM
Once both sides were mounted I installed the folding arms and locked them into place. I set the teak platform in place using a 1/4 spacer between the transom and boat and made sure it was centered side to side.

You also have to be care to make sure the arms are parallel to each other before attaching the deck this ensures the arms travel in the same arc to prevent binding in the brackets.

Once I was happy with the location I drilled the holes in the teak and attached the new arm using the original wood screws.

09-17-2007, 10:37 AM
Both sides drilled and mounted.

09-17-2007, 10:40 AM
And finally here is the platform folded!

09-17-2007, 10:42 AM
Looks Awesome Diesel!! How far off the ground is the platform when it is folded?

09-17-2007, 10:52 AM
Depends upon the height of your tongue jack. On mine it's about 2" from the ground with the tongue at my normal "unhook" height.

09-17-2007, 11:03 AM
That thing is NICE... bummer I cannot use it because there is some raised parking block type of area of concrete at the back of my garage.

07-27-2009, 03:54 PM
Does anyone have a set of brackets that would fit a 1988 prostar 190, I broke my left side (port) swim platform bracket, trying to straighten. Thanks. Troy 952-406-0369

XPC Sealman
07-27-2009, 04:18 PM
Diesel, we want to thank all of you for your support. Your detailed post is perfect! Thanks for all of your help~

07-27-2009, 08:57 PM

07-27-2009, 09:05 PM
Does anyone have a set of brackets that would fit a 1988 prostar 190, I broke my left side (port) swim platform bracket, trying to straighten. Thanks. Troy 952-406-0369

If you can't have it repaired and can't find replacements, consider these, http://www.mastercraft.com/teamtalk/...highlight=fold (http://www.mastercraft.com/teamtalk/showthread.php?t=29738&highlight=fold), final install, post # 60 and #61

04-15-2010, 07:07 AM
Just spoke to Eric via email, they have a kit for the '85 hull now. $270. Ordering in a few weeks.

05-03-2017, 08:20 AM
I am wanting to purchase the brackets. but i am having trouble getting to "www.mymastercraft.com" does anyone know how to reach mike?

05-03-2017, 08:39 AM
I believe OJ stopped production of these brackets a while back. The only way you are going to find them is on ebay or other after market sales points.

05-03-2017, 09:23 AM
Did you fill the original holes?

My 2011 has this bracket and it is great. It hangs about 3 or 4 inches off the ground. I lower it, then back the boat into the garage.