One of a Kind Diesel B

My fascination with John Deere tractors goes way back.

My dad had an “A” and a “B” on our farm that he taught me to drive when I was very young and I’ve been on one ever since. Although the Deere is a fine machine, I enjoy making them into what I would like in a tractor—customizing them, I guess you could say. I’ve changed the way the traditional two cylinders are supposed to sound, for example.

Some of the rusted-out pieces of junk that I have brought home have prompted my wife to say, “Are you sure that’s worth restoring?”

But when I’m done, there’s a much different comment: “Now it looks as good as the day it rolled off the showroom floor!”

My first conversion was a 1944 JD “A” that is now powered by a 240 horsepower V-8 diesel engine. This tractor is very unique and has drawn much attention throughout the United States and Canada. My second conversion was basically the same, except I practiced on one of those “red” tractors.

Last summer, the 1995 model was produced. It was also a 1944, but this time I went back to green and used a JD “B.” As you may know, John Deere never made a JD “B” diesel, so I thought I would be the first to try. The ’44 I started with had a six-speed transmission and I jumped back a few years to find a 1939 engine block, cylinder head and governor housing. These were used to gain the 17 to 1 compression ratio that would be high enough for combustion.

The block was bored for JD 4430 sleeves and pistons. JD “A” connecting rods were used and bearing inserts were installed (bear with me on all the technical terms, but this needs to be explained in order to understand how this became a reality). The injectors came from an 1850 Oliver and were installed through the cylinder head to accommodate the pre-combustion chambers in the pistons.

The injection pump required major work to handle the unique firing order and a gear reduction was built to reduce the injection pump speed.

The cubic inches have been reduced to 156 because the bore is now a 4.250 diameter. It took the fuel delivery of a JD 5020 to make it run on two cylinders.

The JD “B” may be more fuel efficient than a JD 70 diesel if the camshaft was reground to diesel specifications. The cam timing was changed instead and it seems to start well.

The cylinder head was torqued to 150 pounds and the head gasket has held fine with the higher compression and will start at 30 degrees without using a preheater.

The starting speed was increased with a high torque starter. The engine seems to produce twice as much torque at low RPMs than the gasoline engine. The horsepower has been set at 22, which is pretty good considering it’s only 156 cubic inches.

 

 

 

Comments