1-1/4 HP Monitor Gas Engine and Edson Mud Pump

By Staff
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This 1918 1-1/4 HP Monitor engine and Edson Mfg. Co. mud pump make quite an effective team, pumping a gallon of water each minute. George Arney built this pumping outfit from different sources, inspired by a Baker Mfg. Co. catalog showing a similar config
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The Edson pump as it looked after George bought it at auction during a trip to a Fort Scott, Kan., gas engine show.
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A closer look at the Edson mud pump reveals workmanship reminiscent of the pump's condition when it left the factory.
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The 1918 Monitor engine wasn't in good shape. Problems with the cylinder, flywheel and exhaust detent arm plagued the restoration.
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The Baker Mfg. Co. 51E catalog that inspired George to build his mud pump setup.

Circa 1918 Monitor Gas Engine
Baker Mfg. Co.
Year: Circa 1918
Horsepower: 1-1/4
Serial number: 17798
Bore: 3-1/2 inch
Stroke: 4-inch
RPM: 500
Flywheel diameter: 17-5/8 inches
Flywheel width: 2-1/4 inches
Governing: Hit-and-miss
Ignition: Buzz coil and spark plug 

Edson Mud Pump
Company: Edson Mfg. Co.. Boston, MA
Year: 1882?
Additional info: Pumps 1 gallon of water each stroke; “1882” stamped on pump, but no other information is known.

A few years ago, I purchased a Baker Mfg. Co. 51E catalog featuring Monitor-brand engines and equipment. Inside, the catalog shows a photo of a 1-1/4 HP Monitor engine hooked up to a diaphragm pump – sometimes referred to as a mud pump or a trash pump. The only information Baker offers on this setup is a black-and-white catalog photo with a small caption beneath that reads, ‘For Trench Pumping.’ I thought this was a pretty neat-looking setup, and since I collect Monitor engines I really wanted to add this unique mud pump configuration to my collection.

I searched for these mud pump outfits for a couple of years with no luck, so I figured the only way to ever get one was to build it. It turned out that locating the pump was the hardest part of the whole project – I wasn’t even sure of the pump brand in the catalog, but I didn’t let that stop me! I got my lucky break while attending a gas engine show at Fort Scott, Kan. An auction was planned at the show, so after making my rounds through all the engine displays I headed on down to see what they were going to auction. I could hardly believe my eyes when I walked up on a mud pump. Right there before me sat the pump I had been searching for! Built by the Edson Mfg. Co. of Boston, the pump was kind of rough, but nothing major was wrong with it. It isn’t the same shape as the pump in the black-and-white catalog photo, which probably means it isn’t the same brand, but it would do perfectly, nonetheless. I didn’t stray far from that spot until the pump was mine.

Now that I had finally obtained the most needed part for this project, I was anxious to get started with the restoration. About the only thing I did to the Edson pump was give it a good sandblasting, replace some of the bolts and the diaphragm, and make a new handle. To date, I still don’t know the year the pump was made, although Edson is still in business and still sells the diaphragms for this kind of pump. Additionally, the pump didn’t have a patent number cast anywhere on it, but the number ‘ 1882’ is cast in it. Could that be the year the pump was made? It might be since the company has been in operation since 1859.

I located the engine cart in Illinois. It was priced fair, but it would require a 16-hour round-trip drive from our home in Missouri. I wasn’t really looking forward to the trip, but we made the deal anyway. My wife, Ruthie, and I set out early one morning to get the cart, returning back home with it by late evening.

I purchased a 1-1/4 HP, 500-rpm, hopper-cooled Monitor engine, serial no. 17798, for this project. According to the serial number list, this unit was made in 1918, and it has a 3-1/2-inch bore and a 4-inch stroke. The flywheel measures 17-5/8 inches in diameter with a 2-1/4-inch face. Ignition is accomplished by buzz coil and spark plug. After disassembling the hit-and-miss engine, I found it had a lot of problems – almost every part was worn beyond use and never rebuilt. The worst problems on the engine were a cracked flywheel and a big chunk missing from the cylinder bottom where the rod came loose before it was retired. Also, the exhaust detent arm that attaches to the detent support bracket had been worn to an egg shape, and it had so much play I couldn’t get the beginning or end of the hookup period to adjust out. I had no way to repair those problems, and considering all the broken and worn-out parts, I had almost decided to just part out what I could from the engine and locate another one for the project.

A while later and still no better of an engine, I visited my good friends Bill and Billy Anderson – and I’m glad I did! After telling them about the cylinder and how I was thinking about scrapping the engine, Billy said, ‘Hey, no problem, I can fix that!’ So, I took the cylinder, piston, connecting rod and detent over for repairs. After Billy welded up the cylinder, Bill made the new intake and exhaust valves, and then he re-grooved the ring lands on the piston for the new rings. The wrist pin was worn out, too, so Bill graciously made a new one. The detent was so badly worn the hole had to be reamed out and a new pin made to take out the slack.

In the meantime, while Bill and Billy finished this work, I located another flywheel and drilled out the filler plug to the gas tank. The tank was nearly half full of rust and debris, and the fuel line had a long freeze crack and needed replacing.

Now that I had most everything repaired, the only thing left was to reassemble and paint everything. To my surprise, when I started the engine for the first time, it fired up on the second turn of the flywheel and ran great! In all, this setup weighs about 615 pounds, and the restored Edson pump moves I gallon of water on each stroke.

Most of the square gas tank Monitors I’ve seen were painted gray by the factory, but on my engine only traces of red paint were present, so that’s the color I chose. Even though this engine needed so much work, I’m glad I went ahead and restored it. It was a fun project and has turned out to be a real crowd-pleaser at every show I take it to. These pumps are hard to find, and I had never seen or heard of a setup like this, so I’m guessing Baker only made a limited number. Most show-goers walk by a lot of the other displays with hardly a glance – but not this one! Only a few people are able to walk by without watching for a good while. If anyone out there has an original example of this setup, I’d like to hear from them.

Contact George Arney at: 518 S.E. 921, Knob Noster, MO 65336; arney7@yahoo.com

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