‘The key to building a reliable engine is patience. The details matter and everything has to be just right – especially to produce a lot of horsepower.’

Name: Chance mikkelson
Age: 23
Years on job: 4

Chance Mikkelson learned his trade the old-fashioned way. “I built my first engine – a Chevy V8 – with my dad when I was 14,” he says. In 2007, Mikkelson opened his own shop, Dexter Manufacturing, and works on engines of all vintages and size. “One day I’m assembling the heads of a Maserati V8, and the next I’m resleeving a lawnmower cylinder.” During off-hours, he might be fabricating a fuel-injection system for a Ford Model A. Often, he completes projects for frustrated DIYers. “When guys buy a bunch of go-fast parts,” he says, “the engine rarely runs right. You have to figure out which parts work best together. That’s the fun part.” – Larry Webster

Engine rebuilding in five steps

1. Disassembly

During disassembly, Mikkelson relies on hand tools so he can feel a stripped thread or loose bolt. “A lot of times an engine blows a head gasket because a head bolt was loose,” he says. A careful teardown reveals the engine’s failure mode and wear characteristics. He sorts parts according to their position on the block. Another tip: “Start from the top.”

2. Cleaning and inspection

Elbow grease and an automated steam cleaner remove built-up crud. To reveal tiny cracks in a part, Mikkelson magnetises it, applies a magnetic fluorescent powder to its surface and illuminates it with a black light. The powder collects inside cracks that are invisible to the naked eye.

3. Machining

After carefully measuring every part, Mikkelson works pieces that are out of spec or worn with grooves – like a scored crankshaft – back to proper dimensions. Warped heads like the one pictured are ground back to flatness. Mikkelson often finishes surfaces by hand.

4. Ensuring accuracy

After machining, Mikkelson again pulls out micrometers, a straight-edge and bore and feeler gauges to inspect and measure every part. “Seventyfive per cent of my time is spent measuring,” he says.

5. Reassembly

As with disassembly, Mikkelson uses only hand tools to reassemble the engine. He vacuum tests the heads to check the valves and uses assembly dressing so parts are lubed at start-up. Then he fires every engine on an engine stand. “Hearing an engine fire for the first time never gets old.”