Welding Cast Iron - Manifolds

[rocco16 at sbcglobal.net (Larry Fry)]

I cannot imagine silver soldering a cast iron manifold and would bet money
it could not be done.  You CAN, however, use an oxy-cetylene torch and BRAZE
the cracks satisfactorily (stop-drilling first is a good idea).
Cast iron can be successfully arc welded using a nickel-based filler but it
would take about 250 amps to do it, which would rule out any 120VAC home
welder.
The easiest way is with metallic arc (aka "stick"), so with the right
preparation, i.e. grinding out the crack for a full-penetration weld, it
should be a fairly straight-forward task.
  Larry
sandiego16v



> I have seen several posts recently about OEM manifolds developing cracks
> and being discarded.  (For those not familiar with welding, cast iron [as
> in manifolds, not the railing down your front steps] presents special
> problems and often has unsatisfactory results.)
>
> I ran over this site:   www.muggyweld.com   They claim to have
satisfactory
> solutions for cast iron welding.  1) a combination of two types of welding
> electrodes. Can be done on a 120 volt welder if I recall correctly.  2.
> Silver solder applied using an oxy-acetylene torch.
> they have a couple of nice video demos.  Their customer list, if
authentic,
> is impressive. A small combo pack of their electrodes can be had for about
> $40.  Probably enough to do 4 or more manifolds.
>
> Maybe one of our intrepid welders will test it and give us a report.
Those
> 4 into 2 manifolds are getting more scarce every day.  Maybe we can save
> some.  (According to the site some repairs can be made without removing
the
> manifold.  Wouldn't that be sweet? But who would be lucky enough to have
> the crack on the top in an accessible spot?)
>
> Chris