7 hp Fuller & Johnson Restoration

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Richard Adams' Fuller & Johnson.
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Richard Adams' circa-1914 7 hp Fuller & Johnson as found was complete but needed work.
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Richard with the Fuller & Johnson at home just after purchase.
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The replacement piston (at left) was sourced from a John Deere 620.
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The replacement piston is the correct bore size, but taller than the original, so Richard machined it down as much as possible. He ended up with a higher compression ratio as a result, 4.5:1 versus 4.1:1 stock.
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Machining the cylinder head. The original valve guides were bored out to take larger stems.
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The cleaned cylinder/water hopper during setup for the new sleeve.
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Centering the connecting rod on a mandrel in preparation for pouring new babbitt.
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The cylinder/water hopper, painted and bolted to the engine base and ready for further assembly.
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The crankshaft installed and shimmed, complete with connecting rod, piston and crankshaft oilers.
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Front view of the finished engine.
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The air filter is a Donaldson oil bath filter from a Caterpillar engine. Richard made the aluminum adapter for it.

Circa-1914 7 hp Fuller & Johnson

Manufacturer: Fuller & Johnson Mfg. Co., Madison, WI
Year: Circa 1914
Horsepower:7 hp @ 400rpm
Bore & stroke: 5.5in x 10in
Flywheel dia: 32in x 2-3/8in
Ignition:Igniter w/coil and battery
Governing: Hit-and-miss

After restoring 11 antique tractors, I thought that an old hit-and-miss engine might be fun to restore. A friend, Scotty, just happened to have an old engine of unknown make half buried out in his yard and offered to sell it if I would restore it. It was not stuck, but had no compression. All the castings appeared to be there, and I could find no cracks. After looking through a book on old engines, I found this engine to be a Fuller & Johnson 7 hp made in Madison, Wisconsin, around 1914. Its history, or what it might have been used for, is still unknown.

Getting to work

After getting this 1,200-pound monster home on my small utility trailer I pressure washed it and started its disassembly. After taking off the head I removed two handfuls of rust from the cylinder. The bore and valves were badly rusted and the valve guides were badly worn. After removing the piston and rod I found the rod journal also to be badly worn. The igniter was rusted shut and missing springs. The good news was that all original parts were still on the engine and no cracked castings were found.

Next, I removed the cylinder block from the frame. To remove the crankshaft, the flywheels and timing gear had to be first removed. It sounds easy, but the flywheels and flywheel keys were really stuck. I used heat and penetrating oil daily, trying to pull the keys with a sliding hammer. I thought the keys would never budge, but after 11 days they started to move a little. Finally, after a few days’ work the keys came out. I was cautioned not to use too much heat on the flywheel as the spokes could expand and crack the rim.

To break the flywheels free from the crank, I spun the assembly and quickly slid a wood block between the frame and crank journal, stopping the rotation quickly. The inertia of the flywheel broke the bond and I was able to push the flywheel off the crank with a hydraulic jack. The remainder of the engine disassembly went well. With all parts off, I sandblasted everything except the main bearings that I protected with several layers of duct tape. After close inspection I still found no cracks.

Machine work

The machine work ($$$!) came next. I wanted to have the cylinder bored and a sleeve installed so that the original piston could be reused, but no one made a sleeve 5-1/2 inches x 21 inches long, and I didn’t want to put two sleeves together. I started looking for an oversize piston that would work and found that a John Deere 620 used the same 5-1/2-inch bore. I called around and found a used John Deere 620 piston, 0.125 inch oversize, which was about the amount needed to clean up the bore. As John Deere 620 pistons are sold in pairs, I was lucky to find a supplier with only one piston that he sold me at a fair price. The piston came with rings that were still useable.

The JD piston pins were larger than the F&J piston pins, so I made reducing bushings for the JD pistons and used the F&J pins. This worked out very well. The height from the piston pin center to the top of the JD piston was higher than on the F&J piston, so I machined down the top of the JD piston as much as possible to get the compression ratio down. The original compression ratio was 4.1:1 and it is now 4.5:1; a little higher, but still within reason.

New valves were the next problem. The valves were too rusted to reuse, and the cast-in-place guides were badly worn. I looked for new valves with oversize stems so the guides could be bored to the new stem size, but was unable to find them locally. I found a company out west that could make up what I needed from new Caterpillar valves. They used valves with 9/16-inch-diameter stems, turned down the heads to my specifications, shortened the stems, and drilled out a cotter pin hole in the ends. These valves were perfect.

Next came the outside machine shop work. It is very hard to get anyone around where I am to do an unusual job like this. They may be equipped, but they just “don’t want to mess with it.” That applies to machine work, painting, etc. With apprehension, I loaded up the block to be bored, the valves and head to have the guides bored and seats ground, and the crankshaft to be ground, and headed for a machine shop. They looked at my parts, said they couldn’t help, and sent me to another place. I went to four machine shops, none of which could/would do the work before I found the right place. It was the local Caterpillar dealer. I didn’t know they even had a machine shop until shop No. 4 sent me there. At the Caterpillar shop I met C.T., a real machinist who took an interest in my project. He said he thought he could do all the work required, and he kept his word. His work was perfect, just like I would have done if I could. They had many large machines for large work; however C.T. had to make a special tool to bore and hone the long, 21-inch cylinder. When I got the parts back I was very happy with the outcome.


Next it was time for painting. Most of these parts were very heavy. I could hang some of them from a line, but most required painting on the ground. I was able to find a small patch of original paint, which I had matched with automotive paint. The block, frame and belt pulley were painted upside down, allowed to dry, then turned right side up and painted again. The flywheels, which weigh 175 pounds each, were suspended on a pipe between jack stands so they could be rotated while painting. The crankshaft and connecting rod were painted with gray Cast Blast. Everything went well with no accidents and no runs. The block and frame were put back together at this time.

It was now time to make a carriage to hold the engine. I didn’t have an original to measure, so I made one from pictures in the manual. I bought rough cut oak 2 x 6s, then planed them down and glued them together for the main runners, and full size 2 x 4s for the cross runners. The four parts were glued and bolted together and heavy-duty casters installed. The carriage was finished with four coats of polyurethane. Once dry, the engine was mounted on the carriage with stainless steel bolts. I could now roll the engine around the shop for assembly.

Babbitting and final assembly

Since the old rod bearing was bad and the crankshaft rod journal had been reground, a new rod bearing needed to be poured with babbitt. I had never done this before, so I bought a booklet and learned how. I made a mandrel the same diameter as the crankshaft journal from aluminum and bolted it to a round aluminum end plate. I made two 0.050-inch aluminum shims, placed them between the rod and rod cap and tightened the bolts. I then centered the mandrel inside the rod and clamped it in place. With the rod on its side, I poured the melted babbitt into the cavity. Once cooled down, I removed the bolts, clamps, mandrel and new bearings. I then cleaned up the casting flash, drilled an oil hole, and polished the bearing. Using the aluminum shims, I reassembled and checked the crank to rod clearance with Plastigauge and found it to be 0.003 inch, about what was required.

Some other miscellaneous items that needed attention included the igniter, which needed rebuilding; the exhaust rocker arm, which needed re-bushing and a new pin; and a couple of gears required new bushings and pins. I bought some used oilers, polished them and installed new glass and gaskets.

Now it was time to assemble the engine. I installed the crankshaft and shimmed the polished main bearings to 0.003-inch clearance. The new piston and rod went in next, then the cam gear. I had marked the cam and crank gear prior to removal so that they could be replaced in the original location. The governor, pushrod, and igniter trip went on with no problem. Next I installed the cylinder head with a new gasket I made, followed by the rocker arm, valve springs, igniter and the mixer. The oilers and decals were the last things to be installed.

Before starting the engine I needed to check the timing of the exhaust valve and igniter, activated by the pushrod and driven by the cam gear. With the 32-inch flywheel, one degree of rotation equals 0.2814 inch at the rim. I carefully measured the flywheel, rotated it in the position where the exhaust valve should open, and set the valve lash to zero. I then rotated the flywheel to the position where the valve should close and found that the valve was still open. Something was wrong.

After a couple of days of experimenting, I found the cam gear to be off by two teeth. Someone in the past must have put the timing gear on wrong, and since I had put it back on as it came off, it was still wrong. Once it was in the right place, I noticed two very small marks on the gears where they meshed. I enlarged the marks with a drill for future reference. While closer, the exhaust valve still didn’t close and open in sync. I decided this was due to manufacturing error and there was nothing that could be done. Timing the igniter also took some experimenting, but I finally got it firing properly.

Finally, it was time to start the engine. With fuel in a temporary tank, the oilers turned on, two full priming cups of gas, a new battery and coil, and the igniter connected, I started spinning the flywheel. Nothing happened. I kept spinning the flywheel, still nothing. I took out the igniter, manually tripped it and it seemed to work. I rechecked everything, tried again, but still nothing.

The next day I belted the engine up to a tractor and tried again. Still nothing. I remembered meeting a man, Dave Gardner, at a recent engine show. He told me if I ever needed any help to call him, so I did. Dave came and checked everything out and said it should run. Another friend, Jim Casazza, and I turned the flywheel while Dave worked the mixer and the engine came to life and ran. That was music to my ears. The problem was that I put only two priming cups of gasoline in the engine as the book said. Dave said it needed at least four cups to get started. Apparently, at some point in the past someone replaced the original, larger priming cup with a smaller one. I sure appreciated Dave bringing his experience and knowledge to help get this engine started.

This has been a fun project. There were a few roadblocks along the way, but that is what makes it fun. I am very thankful for my friends Jim and Dave, and a real machinist, C.T. at the Caterpillar shop.

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