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snowslider76
01-10-2011, 01:29 PM
Long story short I cracked my KGB tank and am looking for solutions. I did some digging on here and couldn't really find anything worth while. Maybe I'm looking at the wrong threads.

Anybody else have this happen? What did you do?

I've been through the dealership, they have been helpful but the tank is not included in my extended warranty. They originally plastic welded the crack and it held for awhile but then broke through. I went back and plastic welded it myself and included a mesh screen in there to hold it better. That lasted about a month. I can continue to do this but it's more a band aid then fix.

I could have the dealer replace the tank, but for the KGB that includes splitting the deck which is big bucks.

Talking with some of the techs in the shop they suggested cutting into the tank and having a custom made bag sit inside the tank as a replacement. Which would be my cheapest option. Sounds ok to me, any thoughts?

Thanks for your help.

76S&S
01-10-2011, 01:39 PM
What boat? I removed my hard tanks and they are for sale if you are interested.

MIskier
01-10-2011, 01:40 PM
Long story short I cracked my KGB tank and am looking for solutions. I did some digging on here and couldn't really find anything worth while. Maybe I'm looking at the wrong threads.

Anybody else have this happen? What did you do?

I've been through the dealership, they have been helpful but the tank is not included in my extended warranty. They originally plastic welded the crack and it held for awhile but then broke through. I went back and plastic welded it myself and included a mesh screen in there to hold it better. That lasted about a month. I can continue to do this but it's more a band aid then fix.

I could have the dealer replace the tank, but for the KGB that includes splitting the deck which is big bucks.

Talking with some of the techs in the shop they suggested cutting into the tank and having a custom made bag sit inside the tank as a replacement. Which would be my cheapest option. Sounds ok to me, any thoughts?

Thanks for your help.


Im sorry to hear about your trouble! This is the first I have heard of one of these tanks splitting. Was this caused by water left in the tank freezing, or did it occur while the boat was in use?

CantRepeat
01-10-2011, 01:40 PM
What boat are we talking about? What kind of access do you have to the tank area?

snowslider76
01-10-2011, 01:47 PM
It's an 06 Xstar, the only access I have through the floor board you can remove in the walkway. This opening exposes maybe 10% of the tank, no way to get it out through there.

The tank cracked because the overflow to the flyhigh bags got pinched off and water wasn't able to flow into them so this caused the KGB tank to crack. Jabsco pumps push something like 12psi and the tanks can support 8psi, so if your tank can't vent the pumps will eventually fill it with enough water to crack it. That's what happened (my psi numbers maybe off but you get the idea).

snowslider76
01-10-2011, 01:49 PM
That 8psi should read 8 psi not 8psi

vision
01-10-2011, 01:51 PM
Cut the top of the tank off and place a ballast bag in its place.

CantRepeat
01-10-2011, 01:55 PM
I see, can you get to all the hose connections on the tank? If so maybe opening up the top of the tank and putting a sac inside of the hard tank might be the way to go.

I don't think I'd consider splitting the boat open just to replace a hard tank.

snowslider76
01-10-2011, 01:56 PM
That's what I was thinking, just wanted to see if anyone has done it, how it worked out for them?

MIskier
01-10-2011, 01:59 PM
It's an 06 Xstar, the only access I have through the floor board you can remove in the walkway. This opening exposes maybe 10% of the tank, no way to get it out through there.

The tank cracked because the overflow to the flyhigh bags got pinched off and water wasn't able to flow into them so this caused the KGB tank to crack. Jabsco pumps push something like 12psi and the tanks can support 8psi, so if your tank can't vent the pumps will eventually fill it with enough water to crack it. That's what happened (my psi numbers maybe off but you get the idea).

To my knowledge the only way to get the KGB out of the current x-star is either cutting the tank or splitting the hull and deck. If you just cut the tank you will obviously not be able to get a new tank back inside.

You may want to contact the MC engineering dept.

Eagle Lake Rebel
01-10-2011, 08:02 PM
How big of a crack do you have? Like any other crack, to properly repair it you have to grind the crack out then make the repair. I would try drilling out the crack then patching it from the outside using a heavy plastic patch. Before installing the patch, install a butterfly nut/bolt fastner through it, apply plenty of 5200 for a flexable gasket, pop the butterfly nut through the hole in the tank where the crack used to be, then tighten the bolt. If none of this is an option, cut the tank, call Fly High and put a bag in.

Holman J.B.F
01-11-2011, 04:02 AM
maybe a proffesional welder can weld the patch.......just like the fittings

snowslider76
01-11-2011, 12:06 PM
There are a couple of cracks about 3 or 4 inches long each. Problem is they go from the top of the tank then down the side. Wondering if grinding those out then patching them would work. I'll have to research what your talking about not exactly sure how that would work.

The cracks are in red on my crude 3D model :)

gatorguy
01-12-2011, 05:46 PM
I vote for bag inside the tank. Or buy a new boat and give someone else the problem.

CantRepeat
01-12-2011, 06:05 PM
Does anyone know what the hard tanks are made of? If you can find out that, then maybe you can just search for a generic fix to that material.

craig3972
01-12-2011, 06:06 PM
my 06 xstar has exactly the same problem. I just accept it as part of ownership

Footin
01-12-2011, 08:04 PM
JB Weld....

Eagle Lake Rebel
01-12-2011, 08:50 PM
With the way the cracks are running, drill out the end of the cracks to stop the running and like footin recommended, I'd give good ole JB a try.

Holman J.B.F
01-13-2011, 03:48 AM
Does anyone know what the hard tanks are made of? If you can find out that, then maybe you can just search for a generic fix to that material.

before you cut the tank out ,try something like this in combination with a patch.Make a patch out of the same material as the tank.

http://www.youtube.com/watch?v=I2pQKPxZMd0&feature=related

CantRepeat
01-13-2011, 07:12 AM
http://cgi.ebay.com/ebaymotors/PLASTIC-WELDER-WELDING-KIT-FAIRING-SYNTHETICS-PVC-ABS-_W0QQcmdZViewItemQQhashZitem4cf455be8aQQitemZ33051 6774538QQptZMotorsQ5fAutomotiveQ5fTools

Link to an ebay auction for the air welder.

snowslider76
01-14-2011, 11:14 AM
I refuse to accept the cracks as part of what I have to deal with. The boat ran great before it happened and now I have planing issues and a bilge that is always running.

JB Weld in this application is terrible, I tired it it lasted a day.

I've been using the Devcon Plastic Welder Epoxy, which is working really well, but it's just a band aid not a fix. The pressure from the tank will eventually crack and break it, takes about 3 weeks or about 12 fills and drains.

I'd like to try a patch but don't know what the tank is made out of or how I would shape it to fit right. Or where the heck I buy plastic. If anyone knows the material let me know. I think I would need material that is 1/8" or less so if I had to bend it it would be easy.

ksdaoski
01-14-2011, 01:00 PM
http://www.tapplastics.com/

this place has everything and ships; well has met all of my prior needs-

pretty good prices.

Not sure if they can help determine what type of plastic you currently have.

ddanenberger
01-14-2011, 01:12 PM
Have you tried 3M 5200.

CantRepeat
01-14-2011, 01:40 PM
Wow, look at this product.

http://www.tapplastics.com/shop/product.php?pid=435

TAP Poly-Weld Adhesive: Imagine being able to structurally bond Polyethylene!!! This has been virtually impossible in the past.