I've never used the Right Stuff, so I can't attest to the properties of
it.  The JB weld is being used to replace lost metal and make a smooth
surface for rubber gasket to seat against.  You're not trying to make a
gasket, the way a sealant can.  The epoxy ends up making a new hard
surface, where the sealants will only act as a filling adhesive.   Yes
you'll always need a new seal and some sealant use is appropriate, but
not as a total replacement for the seal or the lost metal.  I'd be
afraid to experiment with RS in place of JB, especially in light of the
labor required to re-accomplish the task if it fails to seal.  Even
worse, if it blows out under temp and pressure, you can ruin the
engine.  I stand by the use of JB for corrosion repair on VW heads and
cases, but as you said, not in the cylinder seal area of the head.

Mike B.

On 1/1/2013 3:25 PM, neil n wrote:
> Checking Ben's web pages (benplace.com) he writes of JB.
>
> http://benplace.com/head_check.htm
>
> So JB is not to be used on the head where the barrel sits?  (higher
> heat, wider heat cycling destroys the JB?)
>
> If a head surface where the coolant gasket sits has minor pitting, can
> the "Right Stuff" be used to fill those voids?  Not saying JB isn't
> any good (obviously it works) but if one is using RS with a new
> coolant seal.....
>
> Neil.
>
> On Sun, Dec 30, 2012 at 2:15 PM, Mike B <mbucchino@charter.net> wrote:
>
>> I've read about using JB Weld on the pitting and have repaired a few WBX
>> myself this way.  I recommend glass-beading of the corroded areas of the
>> outer rubber gasket area until you've got all of the corrosion out down
>> to the bottom of the pits.  Then, multiple coats of JB Weld, gradually
>> building up a perfect surface, followed by a good flat-sanding of the
>> repaired areas.  It may take a few days of applying epoxy, drying time,
>> then sanding to get the job done well.   I have found that not only is
>> this an excellent repair method, but that it goes one step further in
>> preventing the corrosion from returning.  I highly recommend it from
>> personal experience over years of Vanagon ownership.  I've heard that
>> the same method is used even on Jaguar cylinder heads.
>>
>> Mike B.
>>
>>
>> On 12/30/2012 2:56 PM, Scott Daniel - Turbovans wrote:
>>> I've seen some terribly pitted cylinder heads.
>>> and they are not like a normal headcylinder head in which you can just
>>> have the machine shop take off say 6 thousandths.
>>> The like amount would have to be taken off where the metal rings sit,
>>> around the combustion chamber.
>>> Most machine shops are not set up to do that .
>>> Mo' betta to replace head gaskets when they are getting due.
>>> The outer ones are not even really head gaskets in the conventional
>>> sense.
>>> They're outer coolant retaining gaskets.