The Redline Rebuild Buick 401 Nailhead heads to the paint shop

Engines don’t need paint, but they sure look better when they have it. After the last Redline Rebuild update, in which the Buick 401 Nailhead visited the machine shop, the parts are ready for a thorough—and we mean thorough—cleaning and a coat of paint. Davin heads over to the paint shop to get it done in our latest episode.

The first thing you might think is the block was cleaned at the machine shop—so it’s good to go, right? Slow your roll.

“I have always been told to never assemble an engine with parts fresh from the machine shop,” Davin says as he holds a hose nozzle to the oil passages. “With the amount of debris I always end up cleaning out of each passage in the block and heads, I can see why.”

Fine particulate is the bane of a finely-assembled engine. Even small grit can get trapped against moving parts and act as a cutter, wearing down critical parts to the point of failure. A thorough cleaning is cheap insurance and gives peace of mind knowing that all your hard work isn’t going to go to waste just after the break-in process (or even during it).

The key, Davin says, is to use Dawn dish soap, which removes oily residue, together with a wide assortment of brushes. These brushes range from a bore brush to clean the cylinders to a long rifle-style variant that can run through the oil passages in the block to break up and flush out all the fine particles the oil would otherwise pick up and carry to the bearings.

After the water runs clear out of each passage, Davin uses compressed air to blow away the water and any remaining grit. Wax and grease remover take care of the residue from handling the parts and creates a surface to which paint can easily adhere. With masking in place, the paint booth closes and the engine is sprayed.

Davin gets to take a quick break while the paint dries, but then it is wide-open throttle on assembly. If you want to see how the color came out and what other tricks Davin is using to warm over this Buick V-8, subscribe to the Hagerty YouTube channel to receive a notification when each new video goes live.