Cracked exhaust manifold

[pint4]

The center section on my 1933 Series 60 Buick exhaust manifold has a fairly significant crack and needs to be replaced or repaired. I am told the car will accept Series 60 Buick manifolds from 1933, 34 and 35. I am looking for a good replacement. The option is to get it repaired. Are there shops out there that repair cracked exhaust manifolds? I would prefer to buy a replacement if anyone has one for sale. My email address is: pint4@new.rr.com

Thanks.

Bob

[Dave Mitchell]

Williams Cylinder Head in Nevada, IA does an excellent job of repairing manifolds and has done a number of heads, blocks and manifolds for me. They slowly heat the metal, weld it hot and very slowly cool it.

[Friartuck]

Bob, I would recommend repairing your manifold. Muggy-Weld offers two differant grades/types of Arc welding rods for dealing with cast iron. The repair should include a jig (flat surface) for holding the manifold's flanges flat during the repair. Make sure the welder uses a back-stich method and I would preheat the area to to be repaired despite what Muggy-Weld says. The web site offers videos as well.

Chris

[Guest Silverghost]

Many of these repairs are not succssful, or fail because of un-even heating or cooling of the part causing stress to build up.

I find it is very important to pre-heat the manifold, or head in an oven to the highest possible temp (500-600F)then weld very quickly and return the part to the oven for a very slow cool down period taking several hours.

Be sure to grind a V along the crack and drill each end of the crack if possible to keep the crack from running! Make sure the area is very clean.

Brazeing is somtimes better than welding exhaust manifolds as the repair can be made at a much lower temp. than welding!

If you allow any part to cool too quickly or un-evenly stresses build up and it is sure to crack the new repair...

I have heard newly welded parts cracking like glass in the first few min of cooling...

In a glass shop newly blown glass is quickly put into a very high temp oven to cool over 12-24 hours...this process prevents stresses from building up by fast un-even cooling...

This oven cooling process is called annealing and works with cast iron, aluminum, bronze etc...

There also a process called metalizing where a special torch blows cast iron powder, along with heat to repair cast iron... This also works very well!

This cast-iron manifold can be repaired !

Good luck with your repair...

[Friartuck]

Brad, According to Muggy-Weld, their Arc rods have 300% more elasticity than conventional nickel rods, which makes sense for the expansion and shrinking of cast iron. Agree with something the size of a manifold, pre-heating and gradual cooling can only help to situation. Suggest looking at the videos on their website. And I have successfuly used their products.

And BTW, Happy Birthday! <img src="http://forums.aaca.org/images/graemlins/grin.gif" alt="" />

[Guest Silverghost]

Thank's Fiartuck...I will have to try some of their rods!

[Guest De Soto Frank]

Friar,

Have you had any experience with Muggy's Pot-metal repair rods ?