From Drab to Dynamite

A lot of TLC turns a run-down Domestic mud pump into quite a looker

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The elderly gentleman at the parts counter had stopped in to get some things for his Allis-Chalmers B tractor, but when he inquired about the oil field engines outside, the gals behind the counter paged me.

There is frequently a big engine or two sitting with the farm machinery on the lot of my equipment dealership near Sandy Lake, Pa., as I tend to unload my latest treasures there. They often sit patiently until I can get a chassis with wheels or a sled under them to either bring them in to work on or take them home for storage under a roof. On that day there was a 12 HP Bessemer and a 20 HP Franklin Valveless residing among the tractors and implements. I have found that a big engine outside along with my restored vertical Nelson Brother’s kick-start and 2 HP Simplicity in the showroom are great conversation starters, and my ensuing chat with this gentleman held some promise. He left me his card with an invitation to come see his collection. He also mentioned that he had a

Domestic mud pump that he might be willing to sell.

The elderly gentleman at the parts counter had stopped in to get some things for his Allis-Chalmers B tractor, but when he inquired about the oil field engines outside, the gals behind the counter paged me.

Meeting the Domestic 

A few days later found me touring his buildings and surrounding acres admiring his assortment of trucks, engines, tractors, earthmovers and other relics. The very last item he showed me was the previously mentioned Domestic, mostly hidden under a makeshift lean-to with a tattered tarp over it for added protection. Only the front end was easily visible and I could see it had both the builder tag and the jobber tag on the hopper. With some cautious acrobatics I was able to squeeze in alongside enough to see that it was very complete and mounted on a factory cart with twin mud pumps behind it driven by a walking beam between them. The entire machine was painted a drab orange color but was not rusted or stuck. The engine turned freely and came up on compression, and the WICO EK still gave off a good spark. He had told me ahead of time that the gas tank area of the engine base was cracked open and now pointed out the damage while suggesting how it might be repaired. He named his price and we shook hands on it. I had my trailer along but he was too tired to load it and said I would have to come back another day. In the meantime, he promised to look for the missing muffler that he thought was in the main building somewhere.

A few weeks later I was riding shotgun with my winch-equipped small trailer in tow and a willing son-in-law driving. We had no trouble loading the Domestic. Unfortunately, the seller had been unable to locate the errant muffler. Son-in-law Shawn strapped the rig down while I paid the man and took a picture of it at his request. It was the first time in many years that the engine had been fully exposed, and I later mailed him a copy.

I had some other projects already slated but decided to give the Domestic priority as I didn’t think it would take too much to get it ready for the June show at Coolspring Power Museum, where Domestic was the feature. 

The hard work begins 

Although I am an Allis-Chalmers man, I didn’t care for the orange paint job the outfit had been given at some time in the past although it likely served it well in its working life on construction sites. Pressure washing revealed a layer of blue paint under the orange and then a layer of what I took to be the original gray. I prefer my engines to retain their “working clothes” whenever possible but I thought this unit deserved better than the splotchy remains of what had been there before. Besides that, the gas tank repair would leave an area in need of cosmetics, so a complete makeover seemed reasonable.

I tackled the gas tank problem first and began by removing the engine from the cart so I could lay it on its side. The gibb key in the flywheel came out easily with the banana shaped removal tool I had purchased from Harvey Cain several years ago. (Modern hay equipment still makes regular use of gibb keys and Harvey’s tool has helped out many times in our shop.) The flywheel had a split hub and spun off easily after removing the pinch bolt. The magneto was then removed followed by the sideshaft after making some inconspicuous timing marks. After removing some plumbing the broken gas tank casting was fully exposed for repairs. I removed the front section around the cleanout cover by grinding through the only remaining unbroken area with a cutting wheel on the tip grinder. That allowed easy access to the inside of the tank base for a good cleaning. I veed out the cracks in the rear section and was able to gently pry it back down into place and hold it there with the weight of the big pry bar. Patience was exercised in mig welding the cracks an inch or so at a time.

With the rear section done I then coated the inside surfaces of the tank with gas tank sealer by reaching through the opening left by the removed front section. I initially coated the outside over top of my weld also but later removed it due to fear of poor paint adhesion.

I realized the stress of freezing may have also allowed the casting to crack into the water hopper above so after a thorough cleaning of the hopper I put some water in it for a test. Sure enough a small crack directly above the cleanout opening began to seep. At least it was in a good place to get at. I veed and migged it and applied a fresh coat of tank sealer to the weld and also into the same edge of the water hopper from above.

The next step was to fit the front section, mig it and apply sealer to the inside of that area by working through the actual cleanout hole this time. Some careful grinding of the welds and a little spot putty in a few pits had the ugly broken area looking as good as new. The only mechanical challenge was to repair the worn out timing lever detent on the EK mag drive.

I was not sure how it was supposed to function concerning detent action and lever position but an answer to my question posted on SmokStak confirmed my hunch. I reworked the broken detent by migging, grinding and filing, and soon had it working fine.

I am very familiar with shim adjusted bearings that make use of a laminated shim stack because I have worked on Allis B, C and WD tractor engines for more than 30 years, and the Domestic connecting rod fitted up fine with the removal of one leaf from each side. The wrist pin adjusted up nicely with the setscrew on each side of the piston boss. The compression was excellent with no leakage evident past the rings or either valve, and both valves fit well in their guides, so I decided that removal of the head and piston would not be needed.

The Lunkenheimer mixer was stripped and found to be clean and functional. There is no check valve in the line as the gasoline can feed to the mixer via gravity and the screen cartridge at the tank outlet required only minor cleaning. I took the opportunity to add a tee with a drain cock at the outlet.

Time for some elbow grease 

The biggest task yet remaining was to get all the components, including the pumps, cart and wheels, to a point where they all could be painted with good results. Many hours were spent scraping with various tools, buffing with a wire wheel and a Scotch Brite disc as well as using sandpaper and Scotch Brite by hand.

I left some of the steel parts, like the sideshaft, mag trip rod, exhaust valve roller and some of the larger nuts, in the bright to set them off a little from the intended gray of the engine. I coated them with a clear coat before assembling.

According to information on Paul Dieter’s website on Domestic engines, there were various shades of gray used by the company, so I chose Rust-Oleum Smoky Gray for the engine itself and applied two coats by brush followed by a third coat with a foam applicator to reduce the brush stroke lines.

I disassembled the pumps and removed them from the cart. I gave them the same scraping treatment the engine had received although I was intentionally not as fussy since I consider them somewhat less glamorous than the actual engine.

While the engine was apart I painted the inside of each pump and the center plate of the diaphragm assembly with gunmetal blue. I also measured for the diaphragm rubber that was missing from the rear pump and e-mailed Jack Welton in Copley, Ohio, with the dimensions. Jack soon replied with a price and ordered a diaphragm for me along with some others for his store stock. I thought the cart and pumps should be a slightly different color than the engine and was happy with the result I saw when I mixed some semi-gloss black with the Smoky Gray. I put two or three coats of this on the pumps, cart and wheels, and also decided to paint some of the engine accessories with it for contrast.

The EK magneto had been painted orange along with everything else so I removed the outer band and the covers and took them to the wire wheel. I often polish many different metals with a common wire wheel and was not disappointed this time as it left the brass mag pieces with a beautiful luster. I cleaned the points and the coil terminals and reassembled the mag, setting it aside until needed. I had decided early on that such a quality engine deserved brass plumbing in place of the original iron pipe, so I obtained a duplicate of each of the original pipes and fittings in brass over the course of a few weeks as the project evolved. I buffed them on the wire wheel also and sprayed on a clear coat.

The finish line in sight 

I installed and timed the sideshaft, assembled the valve train and fuel pipes, and mounted the flywheel. I installed the magneto and made some timing adjustments to the trip mechanism. I had previously set the pumps back on the cart, and Sunday afternoon I set the engine in place and attached the pump drive. However, I did not install the removable drive key on the flywheel to transfer power to the pumps as the rear pump was without its diaphragm. Everything received some oil, I filled the grease cups and oilers, made sure the governor latch was free and added some gas to the tank.

You never know what to expect when first starting an engine that is unfamiliar to you, but with just a couple spins of the flywheels, she was off and running – and on the original spark plug at that! I adjusted the mixer to a happy spot and let it run for a few minutes before shutting it down and looking things over.

Nothing needed attention except that the spark seemed a little early so I set it back a few degrees. I added water to the hopper, restarted it and let it run while I sat back and admired the beauty of its design.

I showed up a little early for work Monday and had it running when the others came in. They had watched the engine evolve and were excited to see it running. Most people in our industry share an appreciation for fine machinery and my crew is no exception. In fact, our parts manager, Bette, has made the statement that she likes brass better than diamonds!

Not so fast 

Sometimes a fresh eye on a task brings overlooked things to light as was the case when I showed my pride and joy to the visiting Agco service rep. He was enthused about the Domestic but asked if the flywheel was intended to wobble like it did. Bummer! I had been so caught up in the restoration and running that

I hadn’t even noticed the oscillation of the flywheel and the crankshaft nose.

That evening after work I scratched my head awhile and took stock of what materials I had available. The ability to do my repairs at a fully equipped shop is a blessing that I greatly appreciate because there is almost always the materials or tools needed to meet most challenges. I rounded up an old bearing race to use as a loop over the end of the crankshaft and welded it to a section of square stock. To the other end of the square stock I welded a nut with a thread to match that on one of the short Owatanna puller extension legs. The lower end of the puller leg was a long fine thread just right for gradual movement. I clamped a channel iron across the underside of the cart and extended it out past the end of the crankshaft. I slid the threaded puller leg through a hole in the channel and snugged things by hand. I then attached a magnetic base for the dial indicator to the side of the cart with the plunger riding against the flywheel face. By slowly rotating the flywheel I was able to find the apex of the travel and zeroed the dial indicator at that point. The dial made it easy to see the deflection each time I tightened the nut under the channel. I had to go quite away past the center point before it remained where it needed to be when the nut was loosened. The actual tweaking time was only 10 minutes or so after all the thinking and jigging was done. The result was a true running crank with very little scuffing to repaint.

Wrapping up the mud pump 

Within a day or two after that, the pump diaphragm arrived from Jack Welton. And when the invoice showed up a few days later, it was for less with shipping than his original price was for the part alone. (Thanks Jack!)

The next Saturday afternoon found me lifting off the walking beam and the top chamber of the rear pump to install the rubber. It was a perfect fit that required cutting only two holes for the bolts attaching it to the center plate and valve assembly. I engaged the drive key and a dry run showed it was in order to pump water as soon as a tank and suction line was rigged up.

Come Sunday afternoon I was back at it with a tub and an assortment of 4-inch PVC fittings and pipe. I soon had a recirculating system set up. After some priming of the pumps a steady rush of water was moving through but was spraying from the outlets each time a diaphragm went down and a check valve was forced open. This would pose no problem on a construction site but it makes a mess and wastes a lot of water for show purposes. I tried adjusting the stops for the check valves down so they would not open as far but that didn’t help.

After studying the situation for a while I realized I needed to direct the discharge from the check valves to the closed rear side of the top chamber so it wouldn’t spray directly out the open discharge side. The check valves on the Nelson Brothers mud pumps I own are hinged at the outlet side and the result is a nice even flow. The check valves on the Domestic pump travel straight up on two guide rods but fit the rods quite loosely.

I discovered that if I held lightly down on the front side of each valve it would tip and shoot the water to the rear of the chamber. This worked well so I fashioned an L-shaped stop rod for each out of some round brass stock I had and inserted the long end into a hole that I drilled into the front edge of each valve plate. I trimmed the length of the rods so the short leg of the L would contact the underside of the walking beam bracket after the valve lifted a short distance causing the valve plate to tip. Presto! No more spraying of water and, after a copper drip skirt was added under each outlet, hardly a drop missed the tub once the air was purged. I also added a rubber washer at each check valve stop to quiet down the clack-clack made by the valve cycling.

Contact Bill Klein, 726 Klein Road, Sandy Lake, PA 16145 • kleinwp@windstream.net

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