Transom Rot Inspection

[deevo439]

Hi Everyone,
I am new to boating and bought a 92 Four Winns 200 Horizon with an OMC Cobra 5.8. I looked over everything before I bought and it checked out. I felt the transom pushed on it near the transom bracket and all around. It was good. I got it in the water shortly after I bought it and was taking on some water. I had my marina shop guy check it out and it it leaking around the garboard. He pulled it out of the water and removed the garboardand there is signs of rot, chunks come out on the finger. I have used a hammer to tap around trying to figure out how high the rot goes and if it goes into the transom mount and it doesn't sound like it. I what I want to do now is drill a couple of holes and check that way as well. What is the advice on how big of a drill bit to use. I am hoping to do a patch job with filler and resin around the garboard. Reseal the garboard and finish out the summer if the transom mount isn't rotted. I plan on either taking it in this winter and getting it repaired or doing it myself to save 4k. I can post a picture of it later.

Devlin

 

[Scott Danforth]

First, welcome aboard

second, sorry to hear about your transom.

the truth is boats are recreational toys designed to last 15 years and be replaced. your boat is 29 years old. guaranteed that not only is your transom rotten, so are your stringers. i am willing to bet you are also carrying around a few hundred pounds of water in the foam.

as you found, the hammer test means nothing unless the transom wood first got wet, then rotted, then the rotten wood dried out and crumbled to dust to leave a void.

the issue is that long after it gets wet, rots, swells and has lost its integrity, you can tap on the hull and not hear a hollow sound

only two methods that work are a moisture meter and test drills.

to make test drills, use a 1/4" or 5/6" drill, use some tape and mark about an inch from the tip.

from the inside of the hull, start at the keel, and about an inch up from the floor, start drilling test holes. the shavings should be light-colored, dry and smell like fresh cut lumber.

however based on your description so far, you will find that the shavings are dark, wet, and smell of rotten mulch.

go to the DIY sticky at the top of the forum, and go to links 14, 15, 18, 2, 3, 4a, and 4b. read thru all of them, look at every video, etc.

expect to pay the following:

hull restoration, between $2-3k (doing the work yourself)
interior restoration, between $1500 and $2500

and start saving up for motor/drive repairs. OMC went out of business just a few years after your boat was new, and the ford pulled out of the marine market in the mid 90's so your motor isnt supported either. especially if you have an EFI motor (no EFI parts available)

 

[deevo439]

Thanks Scott. I have gotten the manual for my particular engine and am fully prepared to do the work that is needed on it if it so arises. I will get the boat home from the harbor and do some drill testing. Thank you for the info for the holes. I have been scouring threads and videos for the past couple of weeks trying to get an idea if this is something I want to tackle or have some else do it.

 

[tpenfield]

If you can drill from the inside of the transom in the desired locations . . . 1/4" drill should be fine. Even a 3/8" isn't going to hurt anything beyond the existing issue.

 

[deevo439]

If you can drill from the inside of the transom in the desired locations . . . 1/4" drill should be fine. Even a 3/8" isn't going to hurt anything beyond the existing issue.

What should I backfill the holes with when I am done? Just epoxy?

 

[Scott Danforth]

Thanks Scott. I have gotten the manual for my particular engine and am fully prepared to do the work that is needed on it if it so arises. I will get the boat home from the harbor and do some drill testing. Thank you for the info for the holes. I have been scouring threads and videos for the past couple of weeks trying to get an idea if this is something I want to tackle or have some else do it.

go to the DIY sticky at the top of the forum for the links I provided. the answers are there. from that, only you can determine if you have the ability and desire to tackle this. just know, to pay someone to do the work will be more expensive than buying a much much newer boat.

 

[JASinIL2006]

If you are lucky and have dry shavings, just fill the holes with 3M 5200 marine adhesive/sealant.

 

[Scott Danforth]

If you are lucky and have dry shavings, just fill the holes with 3M 5200 marine adhesive/sealant.

based on the description in post #1 and the fact that four winns was an OMC boat like bayliner in 1992....... its almost guaranteed that he wont have to worry about filling the holes.

 

[JASinIL2006]

based on the description in post #1 and the fact that four winns was an OMC boat like bayliner in 1992....... its almost guaranteed that he wont have to worry about filling the holes.

Agreed.