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Davidb
03-09-2009, 11:55 AM
I took my boat out when I first bought it back in September and it took on quite a bit of water in a short amount of time, so I put it back on the trailer and put it up in our shop to work on when I got time. Well, we finally got around to it this weekend. I knew it was leaking around the strut, so I found out what the local MC dealer uses on their boats and bought a tube of the stuff to seal it off. The strut had a lot of different caulking and sealants around it, so I scraped it all off. It ends up that the recessed plate that is fiberglassed in to the bilge that the strut bolts to is cracked more than halfway around the edge. Me and Dad took a wire wheel to it and cleaned it all up. One of the guys that works for Dad who knows how to fiberglass is going to look at it this week to see if it will be something we can do there at the shop. I figure it shouldn't be that hard to fix, but I have no experience with fiberglass. Has anyone ever had this problem?

ProStar Slalom
03-10-2009, 10:29 AM
Not sure if you're talking about a crack in the metal or the fiberglass. My '87 leaked just a little....I mixed up a small batch of fiberglass resin, applied it liberally, and it sealed right up.

TMCNo1
03-10-2009, 11:44 AM
45209I took my boat out when I first bought it back in September and it took on quite a bit of water in a short amount of time, so I put it back on the trailer and put it up in our shop to work on when I got time. Well, we finally got around to it this weekend. I knew it was leaking around the strut, so I found out what the local MC dealer uses on their boats and bought a tube of the stuff to seal it off. The strut had a lot of different caulking and sealants around it, so I scraped it all off. It ends up that the recessed plate that is fiberglassed in to the bilge that the strut bolts to is cracked more than halfway around the edge. Me and Dad took a wire wheel to it and cleaned it all up. One of the guys that works for Dad who knows how to fiberglass is going to look at it this week to see if it will be something we can do there at the shop. I figure it shouldn't be that hard to fix, but I have no experience with fiberglass. Has anyone ever had this problem?

Just to be sure what your referring to, is the leak coming from the area around this, 45210


or this,
45211

Davidb
03-10-2009, 10:03 PM
The first one. It cracked the raised part in the bilge that the strut bolts to. If it isn't called a strut, my bad. That is just what I have been told it is called. It sounded better than the driveshaft brace with a bushing thing.

BriEOD
03-10-2009, 10:09 PM
That is the strut. Some photos would be helpful. But, sounds like you might need some glass work, or something to seal it.

Davidb
03-10-2009, 10:15 PM
Yeah, I thought about taking some but didn't. It is going to be fiberglassed. I was just curious if this is a somewhat common problem.

BriEOD
03-10-2009, 10:17 PM
Well, I wouldn't say it is common. However, I'd wager to say you probably have one of, if not the, oldest MCs on the board. 36 years old and it is original, I'd say that is pretty good.

Davidb
03-10-2009, 10:21 PM
Hopefully it won't be a recurring problem once fixed. But, i'm glad it was only this that was leaking and not something more significant.

Laurel_Lake_Skier
03-10-2009, 10:24 PM
It sounds like you have some fiberglass work ahead of you and that the problem has existed for a while. At some point, someone tried to "patch it up" with some kind of caulk.....obviously that didn't take care of the problem. Was the strut loose at all? It needs to be mounted very solidly. Does the crack go all the way through the hull? As was mentioned earlier, pics would help show exactly what you are up against.

BriEOD
03-10-2009, 10:29 PM
Yeah, I agree with LL Skier. Without seeing photos, I'm inclined to say I would pull the prop, shaft and strut off. Subsequently, I'd refinish the fiberglass in the area to prevent further leakage. While reinstalling, I'd also put in a dripless shaft seal.

http://www.skidim.com/prodinfo.asp?number=OJ2013

Davidb
03-10-2009, 10:48 PM
No, the strut wasn't loose. The leak came from the crack, which is all the way through. We will be doing the fiberglass where it has cracked. Like I said in the first post, one of the guys who works for my Dad knows how to do fiberglass work, so he will be helping me fix it. BriEOD, what is the purpose of the dripless seal? Would that mean that there would be no driveshaft packing to replace anymore? Sorry if this is a dumb question, this is all new to me.

Laurel_Lake_Skier
03-10-2009, 11:31 PM
what is the purpose of the dripless seal? Would that mean that there would be no driveshaft packing to replace anymore?

Right...it replaces the rope seal and does not require replacement/adjustment like the regular rope does. Another less expensive option is to replace the regular wax rope packing with the gore-tex version (its just a bit more expensive than the wax rope), it seals a lot better and lasts far longer than the normal stuff. Use the search feature on the site and check for shaft packing or dripless seals for more in depth information.

Footin
03-10-2009, 11:33 PM
Duct Tape.

TMCNo1
03-10-2009, 11:35 PM
Right...it replaces the rope seal and does not require replacement/adjustment like the regular rope does. Another less expensive option is to replace the regular wax rope packing with the gore-tex version (its just a bit more expensive than the wax rope), it seals a lot better and lasts far longer than the normal stuff. Use the search feature on the site and check for shaft packing or dripless seals for more in depth information.


This search feature also work well, TMC Search by Goo (http://www.google.com/coop/cse?cx=005775850323706454504:8-nmuizykqo)gle (http://www.google.com/coop/cse?cx=005775850323706454504:8-nmuizykqo)

Davidb
03-11-2009, 01:10 AM
Duct Tape.

Haha, I'll give that a shot. Save me time and money 8p

That Gore-Tex packing sounds like a good way to go. Its only about $15 at the most on skidim.com. I appreciate all the feedback guys. I'm glad I found this site, there seems to be a lot of useful information.

thatsmrmastercraft
03-11-2009, 03:37 AM
Haha, I'll give that a shot. Save me time and money 8p

That Gore-Tex packing sounds like a good way to go. Its only about $15 at the most on skidim.com. I appreciate all the feedback guys. I'm glad I found this site, there seems to be a lot of useful information.

Don't be completely fooled - there is a lot of useless information here too. All in good humor, of course.

Davidb
03-14-2009, 03:44 PM
So I finally took some pictures today. Here is where the crack is. It goes around the right edge and both long sides.

http://img.photobucket.com/albums/v381/davidB382/MasterCraft/GatlinShopPics027.jpg

Here is Dad wirewheeling around it.

http://img.photobucket.com/albums/v381/davidB382/MasterCraft/GatlinShopPics029.jpg

We used this Dynatron Fiberglass kit. It came with the resin, hardener, 8 sq. ft. of mat (if I recall), two mixing cups, a spreader, and a few mixing sticks.

http://img.photobucket.com/albums/v381/davidB382/MasterCraft/GatlinShopPics032.jpg

Davidb
03-14-2009, 03:45 PM
Here it is now. I left it curing. It looks pretty ugly right now. When I get in from school next weekend I will sand it and get it painted.

http://img.photobucket.com/albums/v381/davidB382/MasterCraft/GatlinShopPics031.jpg

http://img.photobucket.com/albums/v381/davidB382/MasterCraft/GatlinShopPics034.jpg

Bellinghamster
03-14-2009, 11:35 PM
I'd be willing to bet that someone hit something hard with the prop and cracked the hull around where the strut mounts. Unfortunately the patch you put on isn't going to add much strength, so it's pretty likely it will crack again.

To do a structural repair you need to grind a lot more of the old fractured glass out and feather the repair out to where the glass is solid. I'd grind at least 1/4" off the top, feathered at least 6" all around the "pad" where the strut mounts, then overlay the whole area with 3-4 layers of heavy (>18oz cloth with 3/4 oz. chopped strand mat under and between each layer, or 1708 biaxial mat which is easier to work with and get the air out of) each piece cut smaller so it tapers towards the edges. Polyester resin is crappy for secondary bonds (it doesn't stick well to cured resin). Vinylester resin is better, and laminating epoxy is best.

Davidb
03-15-2009, 12:41 AM
Wow, that sounds a little over my head. So, do you think there is no chance that this will hold? If I have to do redo it that way, I would probably rather have a pro do it. What would be a rough price range on what I would be looking to pay to have that done by a shop?

CantRepeat
03-15-2009, 08:48 AM
I learned my lesson with thinking I could repair a boat. Mine was more cosmetic then what you have there. You're talking about the point where the drive train mounts up. Get someone with knowledge in boat repair to do it.

You've already taken the boat apart so that should save you some money.

bigmac
03-15-2009, 09:58 AM
I'd be willing to bet that someone hit something hard with the prop and cracked the hull around where the strut mounts. Unfortunately the patch you put on isn't going to add much strength, so it's pretty likely it will crack again.

To do a structural repair you need to grind a lot more of the old fractured glass out and feather the repair out to where the glass is solid. I'd grind at least 1/4" off the top, feathered at least 6" all around the "pad" where the strut mounts, then overlay the whole area with 3-4 layers of heavy (>18oz cloth with 3/4 oz. chopped strand mat under and between each layer, or 1708 biaxial mat which is easier to work with and get the air out of) each piece cut smaller so it tapers towards the edges. Polyester resin is crappy for secondary bonds (it doesn't stick well to cured resin). Vinylester resin is better, and laminating epoxy is best.Better listen to him Flounder -- he's pre-med....

bigmac
03-15-2009, 10:04 AM
Seriously though, search Bellinghamster's posts. Some pretty extensive rebuilding work.

Bellinghamster
03-15-2009, 11:46 AM
Price? If you do the removals (I recommend pulling the fuel tank) and reinstallation, and bring it to the glass shop ready for them to grind, I'd venture a guess it'll be in the low $300 range tops if they don't need to gelcoat it.

An hour for them got suit up and grind, an hour to vacuum and unsuit, and half an hour for the lay-up should be more than adequate time. Materials should run around $40, maybe $60-70 if you go for epoxy.

An honest shop may do it for half that $. It's a pretty simple job - easy access, one-shot layup and not cosmetic. They have resin in 55 gallon drums, glass mat on rolls, etc. so you should only have to pay for materials that are actually used.