Welding cast aluminum intake manifolds with Muggy Weld Super Alloy 5
In this video, a Toyota Land Cruiser cast aluminum intake manifold is repaired with an oxyacetylene torch with a size 2 or 3 tip and Super Alloy 5 aluminum welding kit.
To begin, heat the end of the Super Alloy 5 rod and dip the rod into the powder flux. Pre-cleaning the base metal is not necessary thanks to Super Alloy 5’s unique flux, which chemically cleans cast aluminum, removes oil and impurities, and prevents pinholes or porosity.
Broadly preheat the area to be brazed for a minute or so before applying the flux to the cast aluminum part. Watch the flux: when the parent metal reaches the working temperature of 600°F, the flux will turn from powder to a liquid, indicating the metal is ready for welding.
Apply the rod, continuing to broadly heat the parent metal. Alternate between applying the rod and flux and flow the rod out with the torch.
Repeat this welding process until the cut is closed off completely. Don’t pull the torch away for more than a few seconds while grabbing more flux, as the aluminum will cool rapidly.
Notice the technique: dab the rod on while flowing the Super Alloy 5 into the aluminum
After closing the cut, allow the part cool naturally or air cool, then remove the flux with warm water and a wire brush.
- Oxyacetylene is necessary when welding a large mass of aluminum, as the parent metal dissipates heat quickly
- While both Super Alloy 1 and Super Alloy 5 can be used to repair aluminum, only Super Alloy 5 is the only rod effective on cast aluminum
- Keep the flux jar closed between uses to prevent moisture absorption
- If the rod balls up, the intake manifold is too cold–simply discard the balled up rod and add more heat before trying again