�Dave-that sounds better than just filling the crack. I'll have my friend drill the two holes you suggested and make a patch. That makes more sense .
It needs to be good as this is above the gas tank- making tank removal nesscary again if it fails. 
I can't risk having it fail on a test run or after I sell it. 
My other idea was to cutr the pipe off aft of the tank, bring it to be welded, then reinstall with a section of rubber hose to couple them. 
�
That way the tank doesn't need removing again.
�
If there was a Vanagon at my local yard I woul have got a used pipe already, maybe the plastic ones. But I have already had the Van 3 years and I have to sell it by May . I donb't have the time to add any more time to it- I stll have to change the pop-top canvas and seal etc. 

--- On Tue, 3/23/10, David Beierl <dbeierl@attglobal.net> wrote:

From: David Beierl <dbeierl@attglobal.net>
Subject: Re: Solder cracked steel coolant pipe?
To: "Robert Keezer" <warmerwagen@YAHOO.COM>
Cc: vanagon@GERRY.VANAGON.COM
Date: Tuesday, March 23, 2010, 12:19 PM

At 12:53 PM 3/23/2010, Robert Keezer wrote:
> Ok- So I have a� friend who came over yesterday and soldered a one inch crack in one of the steel coolant pipes which cracked above the gas tank.
> I don't trust it, but he persuaded me.

Dear Robert,

I don't either.� Whatever stress split the pipe may still be operating and a soft-solder butt joint has very little strength.

If the split is along the length of the pipe I would recommend either brazing (which may be difficult now that there's solder there) or making a patch that fits the curve and extends a half inch or more beyond the split on the sides and an inch or more on the ends.� I would form this closely to the curve of the pipe.

I would drill a hole -- 3/16 or 1/4 -- at each end of the crack to give stress relief.

I would then polish the pipe shiny bright in the patch area and tin it using plumber's solder and plumber's flux (OR some strong and fancy low-temp solder from jeweler's supply house; I think the brand is Tix and the price is $$$).� Likewise shine up and tin the interior of the patch, and butter it lightly with flux.

Put the patch in place and apply light pressure.� Heat the whole with a torch until the solder liquefies and the patch settles into place.� Move the torch around and don't let things get red hot.� Feed more solder around the edges until it stops accepting it, then let it cool.

I would expect that to last a very long time.

But if the split is around the circumference of the pipe, I think a soft-solder patch would not be strong enough, and you would have to clean it up and braze a patch on.� The three common brazing metals are "bronze," "nickel silver" and actual silver which can be had in several melting points.� Any of them should work but the silver is easiest.� Airco or other welding supply house and ask for the proper flux even if the rods are flux-coated.� If you get low-melting silver, make sure it does not have cadmium in it.� A propane-air torch should be able to reach the necessary temperature and a Mapp-gas torch might.� An oxy-acetylene torch definitely will.

An alternative would be to cut the pipe at the split and rejoin it with a piece of 1.5" ID heater hose, silicone by choice (truck-supply place).� In van terms I would expect that to be "permanent" and it would relieve any stress in that area.

Yours,
David