DIY Welding Project: Expansion Tank | MillerWelds

DIY Welding Project: Expansion Tank [Guide]

Print Article
Andy Weyenberg
Aftermarket and Performance Manager, Miller Electric Mfg. LLC
Share
When you have a leaky or worn-out seal under the hood, follow these instructions to make an expansion recovery tank.
DOWNLOAD PROJECT PLAN

SKILL LEVEL: Intermediate

TIME COMMITMENT: 2 hours

Here's what you'll need to get started.

TOOLS AND MATERIALS

Miller® Multimatic® 220 AC/DC multiprocess welder
Brass filter
6063 or 6061 alloy aluminum round tubing (1-5/8" x 1/8") (5" long)
1-1/2" x 4" x 1/8" aluminum plate or flat stock for the mounting bracket
1/4" aluminum plate or flat stock for the end caps
Hole saw
Sander/grinder
Hand drill

Drill bits (5/16", 7/16", 33/64", 9/16" x 18" fine tap and 1/4" pipe tap)

Vise  

3/32" 4043 or 4943 filler metal 

5/16" rivet nuts (2) 

Rivet nut setter 

1/2" wrench 

WARNING: READ AND FOLLOW ALL LABELS AND THE OWNER'S MANUAL.

STEP BY STEP

Round tubing being cut.

STEP ONE:

Take your round tubing and cut to desired length; remember to deburr the edges. Mine was cut to 5" long.

Operator using hole saw to cut out end caps.

STEP TWO:

Using your 1-3/4" hole saw, cut two end caps out of the 1/4" aluminum. Sand or grind the rough edges if needed.

Operator tapping the end cap for the brass air filter.

STEP THREE:

Using a hand drill and vise, drill 7/16" hole and thread with 1/4 NPT tap for the brass air filter. I used a 33/64" bit and 9/16" x 18" fine tap for the bottom fitting.

Welder TIG welding the end cap to the round tubing.

STEP FOUR:

Set the Multimatic 220 AC/DC to 200 amps, 73% balance and frequency set to 90 hertz; then TIG weld the end cap to the round tubing.

Welder welding to the round tubing.

STEP FIVE:

Take your mounting bracket and drill two 5/16" holes 1/2" from each end and 3/8" from the edge. Weld to the round tubing.

Operator attaching the expansion tank to the plastic case.

STEP SIX:

Attach expansion tank to vehicle by drilling two 7/16" holes into an area with backside clearance, and use 5/16" rivet nuts with 5/16" x 1" bolts and lock washers.

Operator attaching the vent hose to the expansion tank using a wrench.

STEP SEVEN:

Finish by attaching the vent hose to the new expansion tank.

About Andy Weyenberg

Andy Weyenberg headshot
Andy Weyenberg began welding at his father’s business a few years before joining the Army. After going to school for Electro-Mechanical, he started working for Miller Electric Mfg. LLC as a technical service rep and training instructor. Andy has built and raced stock cars since he was a teenager — and now builds high-performance street vehicles while also managing the Miller motorsports program.

Get Project Ideas & Plans

Feeling inspired? Check out our project page for DIY welding projects, including step-by-step guidance, videos and downloadable plans.

CHECK IT OUT

Related Products

Multimatic 220 AC-DC All Accessories 907757-01
Multimatic® 220 AC/DC The Multimatic 220 AC/DC is the only machine in its class that offers users the ability to switch...
Published: