One Good Turn (Deserves Another)

A Free Aermotor is Well Earned, Indeed


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I own a heating and air conditioning company, where my friend, Dave, also has a saw sharpening business. We've been collecting and rebuilding hit-and-miss engines for the past 12 years and have accumulated some fairly rare engines along with some not so rare. We've faced some real challenges, but nothing compares to the engine story about to unfold.


John Montgomery walked into my business three years ago to see Dave about sharpening some saw blades. He saw a few hit-and-miss engines in the process of being restored. After speaking with Dave, he asked me if these engines were mine, so I replied they belonged to Dave and me. He asked if I could fix a steam radiator from his house that he had been working on and thought he had ruined. After explaining what he had done, I gave him a few tips to try. He said he would prefer that I pick it up and fix it myself.

I went to his home, picked the radiator up, returned to the shop, spent about 20 minutes fixing it, and returned the radiator. John asked what I owed him, but since I fixed it and didn't have any of my service men run the call, I told him there would be no charge.

He said for the favor he would give me an Aermotor he had. He had tried to work on it, but was getting nowhere. To say it was in poor shape would be an understatement. It came from his grandparents' farm in Missouri and had been buried in the ground for approximately 50 years, with only part of the flywheel exposed.

I thanked him for the returned favor and headed back to the shop. When Dave and I put wrenches to the nuts, nothing would budge. We then got a 55-gallon drum of ATF, affixed a chain to the engine, dropped it into the barrel and sealed the lid.


Two years later, we pulled the engine out and cleaned it up, yet to our dismay, we couldn't move a thing! We had read mention of electrolysis in an article and searched the Internet until we found an explanation.

At first, we were unable to find Arm & Hammer washing soda, so we tried Arm & Hammer baking soda. This started to work, but after finding the washing soda in Peoria, Ill., the process really went to town. We used a 24-volt battery charger and unplugged it at night. After approximately three weeks of eight-hour days, the parts almost came off with our hands. We were totally amazed. Everything but the piston, which was at top dead center, broke loose. Since there was no head to remove (headless), we had a problem!

We made a heavy-duty puller, and while the engine was "cooking" we tried to move the piston. We applied exterior heat to the cylinder and pulled. We heated and water shocked while we pulled. We fabricated 1/4-inch steel block-off plates with gaskets and sealed off the intake, exhaust and ignition. We filled the cylinder with Rust Buster, WD-40 - any solvent we thought would work - and added an air chuck, pushing 150 pounds of air while heating the cylinder with torches; still no luck. We eventually removed the air chuck and tapped a grease zerk into one of the block-off plates. After all the grease the gun would pump, the rod finally moved - only 1/16-inch, but it took the very last pump to get the top ring of the piston out of the cylinder!

Internal Analysis

Inspection of the parts found that the rocker arm had been broken and repaired, but needed further repair, so we brazed it back together. My brother prepped and nickel rod-welded the connecting rod cap, as it was broken, too. The cylinder walls were only slightly pitted, but a honing pretty well took care of that. The rod babbitt was gone so we repoured. We poured the bearing in one piece using brass stock, which was 0.010" under the crank size. It took five attempts to accomplish this. We then hand sanded and scraped the babbitt to match the crank size, with the crank shims in place. We made appropriate shims, then ordered available parts, such as new valves, rings, needle valve and springs for those parts available and started to reassemble.

We made a cart from scratch, mounted a Blue Star pump for recreation purposes, mounted the engine and fired her up. Not being familiar with an 8-cycle, it took a little bit of thinking, but the engine runs like a champ! We have yet to find the gear and shaft to operate the pump or make all the necessary guards and mountings.

We started this in November of 2004, and 'hit-and-missed' on it during the winter months. I called the previous owner, as well as other people who watched our progress and had seen what we started with. On Saturday, April 17, 2005, they all came over with cameras and could not believe that we were able to breathe life back into this engine. The previous owner said he was going to Missouri within the next month and would try to locate the missing pump gear and shaft to give to us.

There is one thing we discovered about the electrolysis cooking method: It seems as though we lost a bit of tolerance. This only stands to reason that when two parts are bound together and you remove the "binding" rust which had them welded, everything is a little looser. We compensated for this with shim stock, LocTite, etc.

Dave and I never gave up. We had a challenge, but with perseverance and determination we overcame. There were times the two of us had our doubts, but the rewards are so much greater when you accomplish a goal.

Contact engine enthusiast Jeffrey Arch at: 440 Fisher Ave., Kewanee, IL 61443;