Date: Fri, 14 Apr 2000 04:21:06 -0700
Reply-To: Max/Joyce Wellhouse <maxjoyce@IPA.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Max/Joyce Wellhouse <maxjoyce@IPA.NET>
Subject: Re: Expansion Tank
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My 2 cents on the plastic welding. Crosslink polyethylene is virtually
impossible to weld successfully, especially something that's cracked from
old age and excessive heat. Linear polyethelyne is much easier to weld.
the only way I know to tell the difference is to take a nail and scratch
the plastic. if the scratch comes out sort of jagged looking, it's likely
the crosslink stuff. if the scratch is smoother, it's probably linear.
the only repair resin I've had success with in fixing either plastic type
with is a urethane based resin from Old Town Canoe Co. it's $30 for a
kit(roughly the cost of a new expansion tank) and you'd need about 1/10 of
the resin supply to do the repair. After sanding the surface 3" on either
side of the crack, the key is to polarize the plastic with passing the inner
blue flame cone from a propane torch over the sanded area quickly and then
don't touch it again. Then you apply your reinforcing material(kevlar in my
case) afte the resin is catalyzed. Contact bag it and squeegee the excess
air out of the laminate. Several layers in in creasingly smaller sizes will
spread the load on the crack. I'm still not sure the urethane will tolerate
the engine exhaust heat or the water temps experienced. David is right, the
new tank is the way to go.
Max
-----Original Message-----
From: David Beierl <dbeierl@IBM.NET>
To: vanagon@GERRY.VANAGON.COM <vanagon@GERRY.VANAGON.COM>
Date: Wednesday, April 12, 2000 8:41 PM
Subject: Re: Expansion Tank
>At 18:56 4/12/2000, Dan Fleming wrote:
>>Or better yet, does anyone have reassuring tales of how to glue or
>>otherwise repair the seam that splits at the bottom?
>
>It's some variety of polyethylene -- pretty much nothing on earth will
>stick to it. In theory you might be able to weld it, but it's a very
>specialized skill. None of my attempts have ever worked. If you were
>desperate, you could get some of that sticky RV weatherseal goo that comes
>as a strip rolled up with paper -- stick some on the bottom, then reinforce
>with duct tape or similar. That should at least slow it down, prolly stop
>it for quite a while.
>
>david
>
>
>David Beierl - Providence, RI
> http://pws.prserv.net/synergy/Vanagon/
>'84 Westy "Dutiful Passage"
>'85 GL "Poor Relation"
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