Norm’s Backhoe

platypus20 · #1 05-31-2023, 09:04 PM

One of the members, NormW and I have worked together on various projects, our latest is Norm’s homemade backhoe. It’s a heavy C-channel frame, with an early GM front axle, a rear end of vague origin and questionable parentage. The original engine was a Volkswagen Rabbit diesel engine, after numerous years it was exchanged with GEO Metro 1000 cc, 3 cylinder gas engine, the engine’s transmission, drives a GM truck transmission. A while back the brakes in the rear axle became inoperable, as it of unknown parentage, making parts a problem, we came up with a different option.

Using a mixed blend of cast off parts, we are installing a disc brake on the outlet of the second transmission, in front of the u-joint on the outlet yoke. The disc brake caliper is off a 1983 Chevy Chevette, using it pads, the master cylinder is a hydraulic clutch unit off of a 1974 Datsun sedan, the disc is one I machined out of a piece of certified 3/8” boiler plate.

I machine the plate into a 9.75” OD x 2.50” ID disc, machined a step in the yoke shaft, pressed the disc onto the yoke and welded it on. I chucked it up it the lathe and had extremely minimal runout. Norm installed the yoke/disc assembly on the backhoe, ran the engine and said he could see no runout.

Tonight I machine the caliper bracket to gain a slight bit if clearance and threaded the mounting holes to 12 mm x 1.75 mm, for the mounting bolts. Today we took a few measurements, to start on the caliper support bracket, V1.0.

Here is a picture of the disc installed on the transmission yoke