A Rusty Lump of an Engine?


| July/August 1998



Fairbanks Morse Jack Junior engine

J. Gordon Hayes, 46A Jeffreys Road, Fendalton, Christchurch 5, New Zealand, went to great lengths to restore this Fairbanks Morse Jack Junior, #115566and the engine brought a new friend great lengths to visit. See the story inside.

46A Jeffreys Road Fendalton Christchurch 5, New Zealand

Back in 1990 at our main show for the year, a spectator said to me that he had found a rusty old engine on the place he was clearing that had belonged to his late father. Well, I went around the following weekend. There it was, an unusual looking rusty lump of an engine. Well, the challenge was there, so I took it on. Got this home and after a lot of talk amongst the locals, we still didn't know what I had.

After a long study of American Gas Engines yellow book, I decided I had a Fairbanks Morse Model H #115566 Jack Junior. It was in a real bad way. Piston well seized, drive broken, springs rusted away, governor gear bent and unusable, in fact if it wasn't such a find, I may have left it.

I stripped it down and put all the parts in diesel oil to soak. I hitched the body on end and suspended it so I could fill the bore with diesel. Being it was headless I could not get in from the front end. I hung the engine like this for months, waiting for the diesel to penetrate down the bore. I applied gentle heat to thin the lubricant. I used a light bulb suspended into the bore to warm things up. I hung about 150 lbs. of weights on all this to assist. I see from my diary I left this for four months. One day I said to myself 'that is enough.' I got the lot down, bolted a slide hammer to the con rod and with a few whacks the piston was out. It was now time to examine the bore, which I decided was not too bad. A good hone will fix that. Now for the hopper. In the headless engine there are two large bungs that come out to service the valves in the bottom of the hopper. These of course, were rusted solid. I tried heating the whole thing in a welding oven, in an endeavor to break the rust, but to no avail. Only one thing to do bore them out. Now these bungs were about a foot down from the top of the water hopper and not easy to see when one has the drill in there and, of course, I had to ensure the thread wasn't getting damaged. Eventually, they were out. Had some brass ones made to replace these. The valve stems were rusted badly and one of the valve guides was broken, so new ones were made. Out with the ignitor that took some cleaning. Had to replace the springs and the insulation. Made a new fuel tank.

About this time, I decided to write to Gas Engine Magazine Reflections for assistance. See 27/5/1. From this request I only received two replies. F. B. Jack Juniors are not plentiful. Neither of these readers had a running engine. George Lewis of Zanesville, Ohio, offered to have copied his splash guard for me, which he did, and sent it out. George has a Jack Junior and he required springs, sketches and pictures of the governor mechanism which I was pleased to oblige with. I wrote to a number of publications in the United States seeking booklets, pamphlets, anything I could find about my engine. I learned, this engine being an early one, did not have a name plate, only a decal of course no decals are available, so I did the next best thing I copied one from a booklet the best I could. Meanwhile, I corresponded regularly with George Lewis, but he had not started on his engine. I worked steadily away. Welded up the broken drive gear. Fitted new rings, straightened up the badly bent governor levers and decided it was time for the paint.

Now, the only thing I knew about the color was a very dark green, almost green/black. So the engine was painted. After all this trouble I had to complete the job properly. From my booklets I found the dimensions of the original truck, so I copied them. I also copied the wheels, so the truck is an exact replica of the original.