’42 Mercury Woodie: Driveline Rebuild

Woodie in the house! Carl Bigg’s ’42 Mercury has loads of character. It’s also extremely rare. Just over six hundred were built before production was cut short by World War II.

Longer and a little more luxurious than their Ford siblings, these Merc woodies were among the flagships of all of Henry’s cars. Carl’s car probably enjoyed a great life, but eventually it was literally put out to pasture. At some point in the 70’s it was rescued from its resting place in an orchard by a young surfer from Santa Clara. He treated it to an amateur restoration, then drove its wheels off; Early Ford V8 Club event tags from throughout the western U.S. decorate the maple header above the windshield.

Wabi Sabi is a Japanese idiom that describes the kind of rough, natural, imperfect beauty that only comes with age. We call it patina, and this woodie is loaded with it. Carl has done much to fix things on the car without disturbing its natural state of grace, but recently its driveline began to complain. The engine ran rough, it wouldn’t hold oil pressure, the transmission was popping out of gear. It was time for some attention.

It was also time for an update. These cars were big and heavy, so Ford loaded their transmissions with a low, 29 tooth gear cluster. He also gave them a stump-pullin’ 4:11 rear end. At 50 mph Carl’s flathead was screaming for mercy. Our plan included rebuilding the motor (with a little added grunt), rebuilding the trans, and switching the ring and pinion to a more freeway-friendly 3:54. We’d keep the 29 tooth cluster, as this would give Carl the low and second gear ratios he’d need to move the big car through local traffic.

Carl, bless him, had the underside of the car and the engine bay steam cleaned before bringing it in. We pulled the engine, pulled the heads, and spotted one issue immediately. There was a bent exhaust valve at the number 7 hole:

Of greater concern was a crack on the other bank. It ran down the cylinder wall, under the seat and halfway down into the valve pocket. Granted, these cracks can be “stitched” together, but it’s an expensive repair. It also indicates the potential for other cracking in the block. A couple of days later, after a more thorough cleaning and closer inspection, we discovered a second, smaller crack in the same barrel on the intake side. We’d be better off starting with a better block.

Opening the transmission revealed the need for some major dental work; teeth were damaged on the cluster, the low/reverse slider, and the reverse idler gear. The synchro teeth on second gear were also wasted:

The case itself was in pretty good shape, so an order was placed to Mac Van Pelt for all the hardware it would take to whip this tranny back into shape. Mac is our go-to guy for parts and advice. His book, The Ins and Outs of Early Ford Transmissions, should be on all your bookshelves.

So, the hunt is on for a better block, the parts are on order for the transmission, and Carl is cleaning up the engine bay and firewall. Drop back by, we’ll be posting updates.