Quest for the Perfect Engine

4 HP Mogul sideshaft engine

This 4 HP Mogul sideshaft engine is owned by Jeff Wahl, 9709 Ripple Run Court, Fairfax Station, Virginia 22039.

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9709 Ripple Run Ct. Fairfax Station, Virginia 22039

The quest for the perfect engine for the Wahl Family Gas Engine Collection has finally ended. We always used to say, 'A Mogul sideshaft engine, now wouldn't that be a nice engine to have?' The sound of a Mogul quietly purring away was always music to our ears. Well, my dad and I finally decided to hunt down a Mogul for our collection, and we purchased a 4 HP Mogul sideshaft in November of 1995.

We bought the Mogul from a friend who shares in our engine enthusiasm, but only likes to play with the bigger toys. We had visited him many times, and the picture of a neglected 4 HP Mogul sitting in his machine shed was one of the reasons we decided to purchase the Mogul and one of the reasons why he was willing to sell it. The engine was in original condition and on original skids. It looked to be in good shape, but as with most unrestored engines, it turned out to be a much bigger project than we had expected.

Although my dad and I bought the engine, we left the restoration up to my grandpa, Harvey Wahl, for many reasons. One, the engine was located in Iowa and we live in Virginia, whereas my grandpa lives in Minnesota, just one hour away from where the engine was located. Two, the Wahl Family Gas Engine Collection is displayed, as it has been for the past 31 years, in Minnesota at the Butterfield Steam & Gas Engine Show. And three, my grandpa always does an excellent job of restoring gas engines, if an engine has all the pieces, my grandpa can make it run to perfection.

After the terms were agreed upon, Grandpa picked up the engine on November 19, 1995. Because the frigid winter was just around the corner in Minnesota and my grandpa wanted to be able to work on it, the engine was stored in our friend Mylan Larson's heated garage. The first job was to disassemble it, check for wear, and clean the engine. Every part on the Mogul was removed except for the six bolts that connect the water hopper to the base. This was done very carefully due to the complexity of the engine and its parts. The sideshaft mechanism was carefully diagrammed and parts were carefully marked so that they would be put back together properly. Little did my Grandpa know that the sideshaft mechanism would come back to haunt him.

Parts were then cleaned, some sandblasted, and some were remanufactured because they were badly worn. New piston rings were ordered from Starbolt, and the cylinder was honed in preparation for reassembly. Harold Larson, an excellent machinist from nearly Hadley, Minnesota, was given the challenge of machining a number of much needed new parts. He machined a new wrist pin and brass bushings for the piston since the originals were badly worn. Also, he machined a new plunger assembly and other parts for the fuel pump, as the originals were pitted and rusted. The valve guides were worn, and both the exhaust and intake valve heads were completely rusted off. My grandpa found new valves from a 1941 Model A John Deere tractor with a stem diameter of 1/2 inch. The original stems were 7/16 inch, so the valve guides had to be bored to allow for the larger valve stem. The stems were then cut to the proper length and threaded to match the original valves. The exhaust valve seat was completely gone and it appeared to have been repaired once before. Mylan was able to clean away the remains of the old seat and weld in a new seat. The valve seats were then resurfaced to ensure a proper fit with the new valves.

One of the rocker arms had been previously welded. During the initial reassembly of the engine, Grandpa found it was impossible to get the valves in time with the piston stroke. Finally, after removing both rocker arms and comparing them, he determined that the welded rocker arm had been welded approximately one inch off from the correct position. The rocker arm was then cut at the weld mark, ground smooth, placed in a jig which was made using the good rocker arm, and re-welded. It was now possible to time the engine properly.

The final step before reassembling was to build a cart. My grandpa decided to build a cart because the Mogul engine is quite tall and, without an original cart, most other carts would have placed the engine too high off the ground. Used grain elevator wheels were used for the cart wheels. My grandpa made an iron base from 2' x 5' channel iron that was cut to the same length as the original skids. After the base was made, only a tongue was needed. Grandpa and Mylan made the tongue out of some pieces of black walnut, which were routed on the edges and strengthened with pieces of angle iron. Pieces of wood were then mounted crosswise on the channel iron base for the engine to rest on.

In May of 1996, my grandpa and grandma made their annual flight to Virginia to visit us. This time they had a special treat for me. They had pictures of the Mogul completely assembled on the cart and a video of it in its recent running condition. Although it wasn't painted, the sight and sound was more beautiful than I can describe.

After the visit, my grandpa returned to Minnesota and spent most of the time working the bugs out of the engine. He didn't paint the Mogul until a few weeks before my family and I showed up for the annual show because he didn't want to damage the paint job while he was removing parts. When we finally arrived at the farm in the summer of 1996, the first thing we did after we hugged was rush over to see the engine. It was completely painted and extremely beautiful. Then we decided to start it up for the first time since it had been painted. I grabbed a flywheel and my dad took the other one and it started up after just a few turns. Its constant puff. . . puff . . . puff lit a smile on my face instantly and the engine sounded much better than it did on the video.

But a 'few problems also showed up for the first time. Almost every gas line was leaking at the joints. After cutting gaskets for each one and taping the threads, that problem was solved. Then the brass gas line from the fuel pump to the carburetor was leaking gas, and after disconnecting it we found that it had a small pinhole. The hole was soldered and everything was put back together and then the paint was touched up.

While we were running the engine we ran it off of a battery instead of the magneto. My grandpa hadn't been able to start the engine with the magneto, but had just recently discovered that many years ago one of the two magnets had been put on backwards. Because he had carefully marked the way in which he found them, he was trying to start it with one of the magnets backwards the whole time. He had recharged the magnets and put them back on right, but hadn't had a chance to try it out yet. So while the engine was running, he carefully switched from the battery to the magneto and it ran perfectly. Then we decided to try to start the engine off the magneto and it started instantly.

The Mogul was now ready to go to the show. We loaded her up along with her 1 HP sister and left for Butterfield. When we got there, I registered the Moguls under my name. My grandpa has been exhibiting at the Butterfield Show for every one of its 30 show years and it was the first time I was registered as an exhibitor. I received my own button and my own plaque, which featured my grandpa's 10 HP Flour City gas engine. While at the show, I enjoyed showing my Mogul to all of our friends and a fortunate event happened.

The engine had always had a little clanking sound that my grandpa just couldn't seem to locate. Well, our friend whom we bought the engine from also shows at Butterfield, and he came over to look at the finished project. He heard the clanking noise and pressed his hand against the eccentric at the end of the sideshaft that operates the gas pump. The sound completely disappeared, and it ran so quietly that I thought I had ear plugs in my ears. So my grandpa is going to repair the eccentric so it will sound even better in the future.

Now I would like to thank a few people who were involved in the restoration of this engine. I would like to thank Harold Larson for doing a perfect job in machining the parts that this engine needed. He is greatly responsible for the way this engine runs so smoothly. I want to thank Mylan Larson for all of the work he put into the engine, and for allowing use of his heated garage. I also want to thank his family for all of their help and putting up with the engine. I want to thank my Uncle George who spent a lot of time touching up the paint, and my Grandma who put up with Grandpa restoring yet another gas engine. Finally and most of all, I would like to give a big thank you to my grandpa for making this engine look so beautiful and run so smoothly. Once again you outdid your-self.

P.S. Currently my dad and I are restoring a 6 HP Mogul sideshaft engine that we bought in Maine in the spring of 1997. The engine is in mint condition and we are looking forward to cleaning it and getting it painted. I guess you can say we are hooked on Moguls.