Oil Field Engine News

25 HP Valveless


Scott Van Diepenbos’ finished Valveless engine, painted.

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August and September are two active months in the oil field engine hobby, Aug. 22-26, we have the big rendezvous in Portland, Ind., where we will celebrate the seventh anniversary of the society. Then Sept. 13-15, we have the West Virginia Oil and Gas Festival in Sistersville, W.Va., which is a show very well suited to the interests of the oil field engine enthusiast.

I would also like to note that if you happen to see Phillip Sparks of Irvine, Ky., at a show this season be sure to congratulate him on being our 2007 honoree for the OFES Rube Goldberg Award. Phillip is an avid big engine hobbyist and has been instrumental for many years, helping introduce people to the engine hobby.

In other news: Recently we received a nice letter here at the society from Scott Van Diepenbos of Bourbon, Ind., detailing his recent project restoring a 25 HP Franklin Valveless engine.

Scott wrote:

I have a 25 HP Valveless engine I bought in Bluffton, Ind. It belonged to Dewight Gerber; he told me the engine was from Michigan and that it was already off the oil wells when he bought it.

The engine was stored inside and was not stuck but it still had problems. The water jacket was completely full of rust and I believe this build-up came from years of condensation from being in a building without heat. I know everything in my barn sweats several times a year. With the rust like it was, the condensation would stay in the pores of the rust and cold night temperatures would freeze it. This caused cracks in the head and jug just like it would if it had been filled with water.

The first thing I did when I got the engine home was to try and get it running. I found the head was warped from the cracking so I had it surfaced in a flywheel grinder. I made a new head gasket and put the head back on.

I then had to figure out how the gas hooked up to it. I talked to a guy from Wisconsin who had a 40 HP Valveless and he told me how to hook it up and about the proper pressures to use. After a few tries with the engine not starting I knew I needed more than me to crank it, so I belted it to my tractor and with a few adjustments it started. I could tell when it started that it was blowing by the rings, but I knew now it would run. It was time to tear it down for repairs.

I took the head and cylinder off and started working to get the rust out of the water jacket. I used muratic acid and a piece of rebar to chisel out rust; it took about a week to get all this rust out. I started to work on the cracks: I preheated the head and brazed the cracks on the water jacket side, and I welded the crack on the combustion side with nickel rod. The welding distorted the head and I had to resurface it a second time.

I decided to try JB Weld in the cracks on the jug. I ground them and filled them, but after I had the engine together and running it leaked a little. I looked for a weld rod with a low preheat so I would not have to take the cylinder back off. I used Palco 808 and it worked.

The piston ring grooves had a lot of wear in them so I re-cut the grooves on a lathe and had new rings made to fit the wider grooves. I put the cylinder, piston and head back on the engine. Next, I checked the bearings to see how bad they were. I took a couple of shims out of the wrist pin bushing to tighten it, but the main bearing had more wear and the right bearing had about 1/8-inch of play in it from years of pulley load on that side. So I pulled the crank forward and poured some babbitt in the gap to fill it. Then I re-shimmed the main caps for proper clearance. I cleaned and repaired the oiler, replaced the oil lines and repaired the governor. Finally, I mounted the engine on a wagon running gear so I could move it around, mounted an old air tank for cooling water and plumbed the water and gas lines.

With all that done I just needed to paint it. I took a piece of the engine that had paint on it to a paint supply company and had paint mixed to come close to the color that was on it; then I filled, primed and painted the engine.

Contact The Oil Field Engine Society at: 1231 Banta's Creek Road, Eaton, OH 45320-9701; oilengine@earthlink.net; www.oilfieldengine.com