Transom Coring

kordo

I'm in the middle of re bedding the D bolts in my transom and noticed that the coring seems to be made up of two materials.  Take a look at lower hole in the attached pic, the material closest to the camera is darker than the material farther away.  It is not due to moisture, both areas are bone dry.  The upper hole is the same, just not noticeable in the pic.  Anyone know what the coring is in a 360 and presumably most other models?  Thanks.

Liberty44140

Probably around 1/4" of glass/epoxy followed by wood core and then 1/8" or so of glass/epoxy inside in the engine room. 

kordo

Yes, but if it was epoxy, then you would expect the entire hole to be coated. If only part of the hole is epoxied then it wouldn't really do much to prevent water intrusion, since the wood is exposed.  Thanks.

Liberty44140

Correct, but that's how most boats are made including Rinker. They don't coat the entire hole when making the boat. They drill and attach the part. You should now drill the hole bigger and fill with epoxy, and then re drill, so the wood is now sealed. But Rinker is just going to drill through all three layers and put the fastener on when making the boat. 

kordo

Thanks, that makes sense to me.  Have you done that mod to your boat, do you know if others have?  I'm hoping that just sealing it properly from the outside will be ok.  Maybe if I have some time, I will tackle the bigger hole and epoxy method.  

Liberty44140

Just last spring I removed my transom lights and trim tabs. Two lights were out so I removed everything to re bed. I drilled all of the holes out a little larger, injected them with west system six10 epoxy, then re drilled the holes. Mounted everything underwater with 3M 4200. Sealant on the outside under water. Nothing was thru bolted so no nuts or sealant inside.

kordo

Nice, a couple questions if you don't mind.  Was there any indication of rot?  How long since the last time the transom lights and trim tabs were sealed? 

By the way, in 2008, I purchased a Mainship 350 from a guy at your marina.  Ted Patrick was the broker.  Trip back to Georgian Bay was lots of fun.

Thank you.

Liberty44140

I’ve heard the name Ted Patrick many times but do t know him. Great boat! My buddy just bought a Mainship 34. 

My boat is a 2007 that sat in storage at a dealer until it was bought “new” in 2011. I just bought it in 2020. From what I could tell the lights and tabs had never been off. If it weren’t for two of four lights out I probably wouldn’t have re done everything but heck might as well re bed it all while I’m there. No indication of rot. I drilled out each hole 3-4 bit sizes larger and then I took an Allen wrench and I cut it down short enough to get it in to each hole. Then used the drill with the Allen wrench as a bit in each hole to grind out as much wood as I could so that when I injected the epoxy I made a nice wide epoxy washer in there. Before injecting the epoxy I vacuumed the holes to get all sawdust, wood and glass, out. The west system six10 is awesome because it is 2 part in a tube that you shoot with a caulk gun in to the holes. Ends are one time use so buy a couple extra. Really worked awesome. 

boatman37

I rebedded everything on our old 1986 Sea Ray Sundancer and when I installed a new depth finder I drilled the holes larger and filled them with 2 part epoxy then re-drilled the correct size. Haven't done that with our Crownline but when I installed our windlass this summer I couldn't drill oversize since the holes were so close to each other so I coated the holes with 2 part epoxy. Hoping to re-bed our whole transom this spring