Toys for Tots

Pennsylvania man crafts motorized pedal tractors

| April 2005

It's every toddler's fondest fantasy: A motorized pedal tractor. Bob Rentzel is the man who transforms those dreams into reality, but with a twist parents appreciate: A healthy dose of safety measures. "It's one thing to make a motorized pedal tractor," says Bob, who lives near York, Pa. "It's a whole different thing to make one that's safe enough to put a child on. I go the extra mile to make these safe."

Bob's fleet consists of four units powered by small gas engines: an Ertl International 56, an Ertl Case 1070, a Play-Trak (made by David Bradley for Sears), and an Ertl John Deere 20. Each tractor moves along at a sedate 2 mph, a perfect match for the average preschooler. "The kids just love them," he says. "Sometimes the parents have to pull the kids off the tractors. A lot want to get right back on."

The seed for Bob's fleet was planted when he saw a very young boy pilot a motorized Farmall pedal tractor in a Pennsylvania show's parade. In 1995, while recuperating from major surgery, Bob decided to tackle a similar project. A longtime collector of vintage tractors and equipment, he was amply familiar with the mechanics involved, and decades of experience working in power plant maintenance had trained him well in safety issues.

Bob's first project was the International 56. He began by cutting out the cast engine area of the body and fitting the tractor with an undermount frame. For power, Bob chose an old-style 1-1/4 hp Clinton because its internal oil pump ensures lubrication at most angles. Bob mounted the Clinton engine on the sub-frame, and he removed the engine's top-mounted gasoline tank, replacing it with two small tanks fitted under the hood, leaving the fuel supply high enough to use the engine's gravity-feed fuel system.

With the engine occupying the space where the steering shaft had been, a new steering system was in order. Bob made a short steering shaft for the steering wheel, passing through two bearings and with a T-shaped coupling just inside the body. A long steering bar extends vertically from the front axle through a bearing at the top of the casing. At the end of the bar is another T-shaped coupling just under the hood. Bob than ran cables from the rear coupling over a small pulley and to each side of the forward coupling. That system worked well, but cable failure was a problem until Bob replaced the cables with weed whip cord.

The clutch on the International is a simple belt tensioner, but since the power pulley is located on the engine's left side, Bob fabricated a crossover shaft for a gas pedal on the tractor's right side. That way, Bob notes, even very young children understand how to make the vehicle "go." Light pressure on the pedal moves the machine forward; release, and the pedal tractor stops. It took three gearing modifications, but Bob finally settled on a pair of jack shafts and sprocket stepdowns to keep the tractor to a speed safe for young operators. The rear wheel hubs are fitted with inner and outer ball bearings and grease zerks for lubrication.