How to Weld a Wastegate Shut

Wear appropriate safety apparel when welding any material.

Welding your vehicle's forced induction system's internal waste gate shut will seal the pressure within the induction system. Installing an external waste gate onto the system then will allow you to adjust the pressure fed into the engine, leading to higher engine performance. Before you begin welding, clean the oil coating from the cast metal surface of the waste gate's inner structure so you can achieve good weld adhesion.

Things You'll Need

• Screwdriver
• Rubbing alcohol
• Clean rags
• MIG welder
• Welding helmet

Instructions

1. Trace the waste gate blow off tube back from its termination point to locate the internal waste gate on the forced induction system. You will find the waste gate at the point where this tube meets the forced induction system housing.

2. Remove the cover from the housing, using either a screwdriver or a socket wrench. Different vehicle manufacturers use different fasteners for this purpose.

3. Clean the internal surface of the waste gate flapper with rubbing alcohol and a clean rag. The valve will look like a round, flat piece of metal that covers a hole leading to the waste gate exhaust tube.

4. Clamp the negative ground cable for the welder to the waste gate exhaust tube, approximately two inches from the forced induction system housing.

5. Turn on the MIG welder and extend the electrode for the welder approximately one-quarter inch from the tip of the welding gun. Set the welder to a relatively low setting. You can easily damage the thin metal of the waste gate flapper if you apply too much amperage to the weld. Set both the wire feed speed and the amperage to the second setting from the lowest setting on your welder. Lower your welding helmet into position.

6. Position the electrode for the welder just over the cast metal portion of the waste gate. Pull the trigger. You will see the weld pool begin to form. Move the electrode in a tight circle to produce a spot weld until the weld pool just touches the waste gate flapper. Quickly release the trigger and remove the welder tip from the weld pool. Allow the spot weld to cool for approximately 20 to 30 seconds before applying the next spot weld.

7. Apply spot welds around the perimeter of the waste gate flapper in the same fashion as the first. Do not allow the welding electrode to actually touch the flapper itself during this process. The spot welds you produce will expand while you weld to join the waste gate flapper to the cast metal housing. Once you completely seal the flapper, you have completed the welding process.

Tips & Warnings

• Do not attempt to operate the forced induction system without an external waste gate once you have welded shut the internal waste gate. This could cause significant damage to your vehicle's engine and forced induction system.

• Always wear a welding helmet when you weld. The extremely bright spark can seriously damage your eyesight.

References

• "Turbo: Real-World High-Performance Turbocharger Systems"; Jay Miller; 2008
• "Turbocharging Performance Handbook (Motorbooks Workshop)"; Jeff Hartman; 2007
• "Street Turbocharging: Design, Fabrication, Installation, and Tuning of High-Performance Street Turbocharger Systems"; Mark Warner; 2006