1989 Chaparral Transom Repair

rad1026

Chief Petty Officer
Joined
May 1, 2006
Messages
443
I had some water leaking in to my bilge last season and finally came to the conclusion I had to pull the transom assembly down to the hull and inspect for rotten wood. Sure enough I have some wet wood at the lower port side of the outdrive cut out. The wet wood is concentrated in the area I am showing and the top and starboard side of the cut out look good. I have chiseled out about 3" and still need to keep going. The chisel is slow going. I have tried a couple dremel bits but they haven't really sped things up much. Does anyone have a better way of getting the wet wood out or should I just use my rotozip and remove that part of the inner transom back to dry wood. Give me some advice here guys, this is my first time with this type of repair and I want to do it right the first time.

So my other question is, why do they use wood here at all. I mean by the time you know there is a problem it is a BIG problem. It just seems like it would not add much production cost to use a completely different material in the transom even if they only used it around the cut out area. It just seems like this type of repair is inevitable at some point in the boats life. What's up with that?
 

Attachments

  • photo238018.jpg
    photo238018.jpg
    195.8 KB · Views: 13
  • photo238019.jpg
    photo238019.jpg
    180 KB · Views: 14
  • photo238020.jpg
    photo238020.jpg
    222.8 KB · Views: 15
  • photo238021.jpg
    photo238021.jpg
    220.5 KB · Views: 14

Bondo

Moderator
Staff member
Joined
Apr 17, 2002
Messages
70,465
It just seems like this type of repair is inevitable at some point in the boats life. What's up with that?

Ayuh,.... Designed Obsolescence,...

Without it, the manufacturers couldn't sell New boats,.....
 

alldodge

Moderator
Staff member
Joined
Mar 8, 2009
Messages
40,581
I would stop trying to get the wood dug out like your doing. Don't touch the outer skin but go inside and start removing the glass away from the wood on the inside. Depending on how accessible it is to get at the inside of the transom, this will decide if the entire transom is replaced or part of it. I just replaced the lower section on my cruiser but there was no way to do it any other way without cutting the back of the boat off.

If you have a small battery powered circle saw, set the depth just shy of the out skin and cut a checker board on the inside. Then take a chisel and break the pieces off.
 

Woodonglass

Supreme Mariner
Joined
Dec 29, 2009
Messages
25,924
Uhhmmm, yeah, I'd recommend you do some searching here on the forum for transom repair. You'll find a LOT of Pics and advice on the Best and Fastest way for getting the job done!!! What size is your Boat??
 
Last edited:

alldodge

Moderator
Staff member
Joined
Mar 8, 2009
Messages
40,581
Nice looking Chap. If you don't have one I would suggest getting a oscillating tool. Harbor freight sells some of the half moon blades which hold up pretty well and fit most all tools.
 

rad1026

Chief Petty Officer
Joined
May 1, 2006
Messages
443
No Title

I have sent the last two hours searching transom repair in this forum and have not really found a situation like I am looking at. Most have an outboard set up with the top of the transom easily accessible, or they are cutting out and replacing the entire transom. There isn't much info on a repair or partial replacement. After looking at many posts here is my thought.
1. Using Rotozip at proper depth, cut around outdrive hole and remove inside layer of fiberglass.
2. Clean wood out of area and from both inside and outside pieces of fiberglass.
3. Treat all exposed wood edges with CPES from the Rot Doctor
4. Reinstall interior fiberglass piece using layers of resin and glass.
5. Plug or tape outdrive cut out and mounting holes.
6. Drill fill holes above cut out and do a 2-3 phase poor of maybe TRK-2000 or Sea cast or some other type of transom repair product.

I really like the idea of having that entire area built with some other material than wood. Not like I plan on anything leaking again, but if it ever does at least its not such a catastrophic event.

Any thoughts on a plan like that?
 

Attachments

  • photo238086.jpg
    photo238086.jpg
    141.7 KB · Views: 6

alldodge

Moderator
Staff member
Joined
Mar 8, 2009
Messages
40,581
I did a partial repair on my Formula, was a real bear, but started on the bottom and kept cutting until I found dry wood. It started out just like yours, I didn't think there was an issue, a one little chip lead to another. There is 27 pages to this one but just skim for the pics. My first pics look pretty much like yours

http://forums.iboats.com/forum/boat-...c-transom-work

Your boat, the get-rot will stop rot IF it gets into everything, but your working on a vertical surface

Just my opinion others will vary
 
Last edited:

rad1026

Chief Petty Officer
Joined
May 1, 2006
Messages
443
Perfect Dodge, that's what I was looking for thanks for the link. Wow, you did a ton of work. I will keep reading though and see how you got it all back together. I will post more pics this weekend when I can get back in there.
 

rad1026

Chief Petty Officer
Joined
May 1, 2006
Messages
443
Yeah, when I removed the transom assembly my port side sacrificial anode bolt broke in half because it was completely corroded. I'm sure that's where all of this started.
 

alldodge

Moderator
Staff member
Joined
Mar 8, 2009
Messages
40,581
I sure hope yours isn't as bad as mine was. Will be looking forward to the pics
 

tpenfield

Moderator
Staff member
Joined
Jul 18, 2011
Messages
17,621
Many boat structures are made of wood. There are pluses and minuses to using wood; moisture and the ensuing rot being the most common 'minus'. When the hulls of boats became fiberglass in the 1960's the structures stayed as wood. Lot of folks don't understand that until they run into a situation like you are addressing.

It is best to cut the inner glass layer of the transom and really see how far the moisture goes.

In AllDodge's situation, it was a judgement call as to how much of the transom to replace. Fortunately, the damage was contained enough to do just a partial replacement.

While you are looking at the transom and the engine is out, now would be a good time to look at the engine mount stringers and even the bulkhead at the front of the engine bay. Moisture tends to travel through a boat's structure like bad news. It is best to know what you are dealing with up front.

I also have threads here about fixing the structure of my Formula 242 and Formula 330. Let me know if you need the links, but they should come up on a search.
 
Last edited:

drewm3i

Petty Officer 1st Class
Joined
Dec 31, 1969
Messages
279
Welcome and good luck! I actually grew up on that exact boat down here in South Florida! Same model, color, and year! My dad bought the boat new at the Ft. Lauderdale boat show in '89 and had it until '04 when he sold it to a mechanically-inclined guy from Georgia. Not sure what his HIN number was, but that's awesome! I loved that boat and we did everything from sandbar hopping and cruising to deep sea fishing and snorkeling offshore in that thing.
 
Last edited:

mxcobra

Chief Petty Officer
Joined
Jun 27, 2011
Messages
526
Im thinking it would be easier to cut and chisel, the old wood out, all of the transom-from the inside. than replace and re glass,
 

rad1026

Chief Petty Officer
Joined
May 1, 2006
Messages
443
Thanks everyone. I am resigned now to the fact the best course of action is to cut away the inner fiberglass and see how far the damage goes. I have a rotozip that I can set the depth. I will hopefully get going this weekend. Its been crazy warm here for Feb. Going to be 70 today with no cooling in sight for the next couple weeks. Albuquerque is a mile high, we have a very dry high desert climate. I have had the boat since 2006. I have never left it in the water overnight. She gets pulled and wiped off. We go to a sand lake so we just put the boat in and pull it out from shore. It didn't start leaking until last year and even then it was such a slight amount I wasn't even sure I was going to go through this exercise. But after ruling everything else out I finally jacked up the front and filled the bilge with water and sure enough I got a very slight drip from the gimble assembly.

Yeah, Drew she is a great boat and does everything we could ask, so definitely worth fixing right.
 

harleyman1975

Ensign
Joined
May 12, 2003
Messages
959
Saw that you were considering the epoxy from the rot doctor. You can epoxy over polyester however you CANNOT put polyester over epoxy. If you start with epoxy you will have to do complete job in epoxy. You can thin polyester to saturate and encapsulate wood. this would be my recommendation. WOG can give you the info on how to thin the poly to use in saturating plywood.
 

Woodonglass

Supreme Mariner
Joined
Dec 29, 2009
Messages
25,924
Your transom is only the centralized portion and does NOT run the entire width of the boat. You will need to consider removing enuf to have ample room for tabbing the new core to the hull. As you progress posting pics will help us to help you. Polyester resin will be more than adequate to get the job done.
 

rad1026

Chief Petty Officer
Joined
May 1, 2006
Messages
443
No Title

Okay, I had just a little time yesterday to poke around some more and take a few more pictures. As you can see from this pic the main Gimble mounting area is thicker then the rest of the transom. I think that is what Woodonglass is saying in the previous post? My plan would be to cut along the edge of the thicker area and begin by removing that down to the outer transom and see if there is any more damage beyond that area. I drilled holes at the bottom corners of the thick area and both sides are wet all the way to the corners.

I spent most of my time with a phillips screw driver and a hammer, poking around for any soft spots on the stringers and bulkhead. I found the starboard engine mount is wet. I'm going to need some help here. The wood going back to the bow of the boat seems really thick, is that a solid piece of wood? How would you go about removing/rebuilding that motor mount? I drilled a hole in the very lowest corner of that area and the bit went right through the fiberglass but there was no wood behind it. The edge of the stringer at the front edge of the motor mount is completely solid, are these two separate structures? How the heck would that area get wet? I did a lot of poking and drilled a hole on the port side motor mount and everything seems solid and dry.
 

Attachments

  • photo238411.jpg
    photo238411.jpg
    237.5 KB · Views: 7
  • photo238412.jpg
    photo238412.jpg
    158.2 KB · Views: 8
  • photo238415.jpg
    photo238415.jpg
    197.3 KB · Views: 7
Top