Oil City Boiler Works/South Penn cross-breed engine, Part 2

By Staff
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When Andrew Mackey finally arrived home from Pennsylvania with a newly purchased Oil City Boiler Works/South Penn cross-breed engine he had quite a few exciting stories to share with his friends at the  North Jersey Antique Engine and Machinery Club. Mackey helped arrange the purchase and retrieval of the engine for the club.
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North Jersey Antique Engine and Machinery Club members began the tear-down process on the Oil City/South Penn by removing the the transfer port cover.
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North Jersey Antique Engine and Machinery Club members began the tear-down process on the Oil City/South Penn by removing the the transfer port cover and the exhaust port ell from the side of the engine.
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Andrew purchased this cylinder oiler for the Oil City/South Penn engine from a dealer at the Coolspring Power Museum show.
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After Andrew got oil flowing freely through the bearings, he spun the flywheels and noted that the crank would spin four or five revolutions before settling at the heavy point of the flywheel counterweight.
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Andrew had to use a 1/2-inch drill bit to remove the degraded cotton in the bores of the bearing body.
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The cylinder head about to be removed. Andrew almost tried to slide it off himself but was smart to get some help from fellow club member Dick Haskins as the piece weighs about 75 pounds.
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When taking a closer look at the piston, Andrew noticed the top of the piston is nearly flat and that there is an approximately 1-inch high deflector about 1/2 inch from the outer edge of the piston top.
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When taking a closer look at the piston, Andrew noticed the top of the piston is nearly flat and that there is an approximately 1-inch high deflector about 1/2 inch from the outer edge of the piston top.

Editor’s note: The following is the unedited version of Part 2 of a multi-part series about the purchase, retrieval and restoration of an Oil City Boiler Works/South Penn cross-breed engine purchased by the North Jersey Antique Engine and Machinery Club in 2006.  The edited version of this article ran in the December/January 2010 issue of Gas Engine Magazine; Part 1 can be found here.

I was back up again, at 7 AM , to attend the Coolspring show. This was my first time there, and I cannot say enough about it! It was FANTASTIC! The theme was ‘ODD and UNUSUAL’ and it was! There were all kinds of engines there, and the show operators were great! I saw quite a few people there, whom I knew, and met a few I didn’t as well. One of the people I met was Dusty Erickson, who wrote the book on the Mietz and Weiss Engine Company. There was a 2 HP Mietz and Weiss engine there as well!

While at the show, I saw 5 other Oil City Half Breed engines, and one South Penn gas oilfield engine, that was mounted on a trailer, similar to the one I was hauling the engines on. I attended the show all day Friday, and Saturday, and enjoyed every minute! I had quite a few queries about the Oil City engine (See Picture 9), and the Charter – Mietz that I had brought to the show.

hile I was there, on Saturday, I found a gentleman who had cylinder oilers for the South Penn and Bessemer engines for sale.(See Picture 10) Some were highly polished, and a few were rough but complete. I figured I could save about ½ the cost if I bought one of the rough ones, so I bought the cleanest of the rough versions and brought it to my truck. It would take another entire article to describe everything there was to see there. About 3 PM Saturday afternoon, most of the exhibiters had left. I now took the time to look around the show grounds proper. What an amazing place! I finally left, about 5 PM, and drove back to the hotel. I had figured, with the load, and the trailer, I wanted to be rested up, and get a jump on local traffic, by leaving early. I had a nice dinner across the street, and headed to bed at 9 PM.

Another close call
I woke up at 4 AM, Sunday morning, got dressed, checked out at the front desk, and soon , and after a safety check, was on my way. For the entire trip home, I worried about running out of gas again, but it didn’t happen. The trip home was relatively un-eventful, with one exception. This exception presented one of the most harrowing experiences I have ever had behind the wheel, and I have had quite a few! Approximately half way back home, I was traveling up a long upgrade, nearing the top. This slope was one of many I encountered that day, and there were many signs stating ‘No vehicles more than 9’6″ wide’. As the trailer was 8’10”, I figured that there should be plenty of room for me. At the top of the long hill, there were 3 signs. First, ‘Maintain safe braking distance, steep downgrade, next 7.2 miles’. OK, that’s why the trailer has it’s own brakes! Next was, ‘Road Side Information’: “This is the highest point on Interstate 80, east of the Mississippi – 2280′ above sea level!”. The view of the surrounding valleys and foothills was fantastic. OK, nice view, now what? The next sign was reflective orange, and had PA Road Department Warning, in big 10″ lettering. Under it in small print were the details. How you were expected to see this small print at 60 MPH is beyond me. The only way I saw it was that traffic had slowed because some poor kid had hit a deer with his car, and pretty well destroyed his front end. The fine print stated as follows: On or about July 1, 2004, this highway will undergo maintenance, and widening, and there will be various lane closures. Be prepared to stop. Maintain 60 MPH. There will be 2 run-off stops, if you have difficulty, coast to one of these stops, and wait for assistance. OK, I thought, that’s not so bad. Little did I know what was in store for me!

Shortly after cresting the hill, and passing the signs, I could see the right lane ahead, with many cones, and signs, stating “right lane closed ahead 1500 feet.”. At the noted 1500 foot mark, a Jersey Barrier (a concrete barrier named after the first state to use them; New Jersey) 4 feet high had been erected at the shoulder, that eventually blocked off the right lane entirely. Still good, I thought, traffic was still doing 70 MPH. A ¼ mile up the road, the scenario repeated. First, the signs repeated, “Right lane closed, 1500′ ” Sure enough, the center lane was now running out.

There were also many signs “Maintain 60 MPH.” This time though, there was a BIG DIFFERENCE! Up coming soon was the right side Jersey Barrier, again, as what used to be the center lane now closed, There was a new addition though, and it scared the tar out of me – there was another Jersey Barrier, on the left side now, and it was set right on the lane side painted line. There was a very large sign, posted on either side of the road. It was painted the familiar red-orange used on the highway, in construction zones. It read as follows: Warning – Single Lane Ahead – 9’6″ Width, Next 7.2 miles. It looked like an old coal chute I had seen as a young man, many years ago. I had to maintain 60 MPH, keeping the trailer within a 8″clearance, for over 7 miles! There were several lane shifts, and only 2 short run off areas, so I couldn’t take a break. Some of the down hill was pretty steep , compounding the stress of driving this stretch. By the time I exited this ‘coal chute’, I was soaking wet with sweat, and my hands and arms were cramping, from gripping the steering wheel so hard! I had to stop at the next rest area, in order to change clothes, and get some water to drink. What a hairy ride that was! After that little adventure, the rest of the drive was a piece of cake. It took 4 more hours of driving, and 2 tanks of gas (at least I didn’t run out of gas again), in order to reach the NJ border. Time for one last fill up in White Township, NJ, and another 45 minutes driving, and I was finally back home. The time was now 1 PM.

I called Blace, and told him I was back, and we decided to take the engine off the trailer the next evening. I parked the trailer in front of my house, and chocked all 4 tires, after which I uncoupled the hitch. (See Picture 11) I again used the winch, this time to unload the Charter – Mietz engine, off the trailer. I tried pulling the engine up the hill in front of the house, with no luck, so I called my son John, to give me a hand. Both of us couldn’t move it. I then used my truck then pull the C-M engine up the hill past my driveway. We let gravity do the rest, although stopping it at the bottom of the drive got a little tense!

Taking it to its new home
The following evening, I again hooked up the big trailer, and drove it up to the Sussex County Farm and Horse Show Grounds, where our club has it’s home base. Blace and I then prepared to remove the engine from the trailer. The first thing we had to do was to decide where we were going to put the engine. We decided to put it inside our display building. I backed the trailer into the end of the building, until it was not able to go further. We then tied a nylon 5,000 pound pull strap around the crank bearing mounts in order to move the engine. An old John Deere tractor was tied to the other end of the nylon strap by means of the draw bar. Some 12″x12′ timbers were laid under the rear lip of the trailer, at the point where the trailer and flywheels would meet. And the engine was pulled to the rear of the trailer. Getting the flywheels off was not much of a problem. Getting the engine’s head end off was a big problem! As the flywheels cleared the tail of the trailer, the entire trailer raised about 4″. This may not seem like a lot, but it was enough, that we did not want to have the head end just drop off the trailer tail, onto the concrete floor. We ended up jacking up the head, with my 2 ton hydraulic jack, and setting a few 2x4s and 4x4s under the head, and the cylinder assembly. After the weight was taken off the trailer, I drove the truck out of the building, pulling the trailer from under the head. Was I glad, when Blace told me he would take it home! We placed some more wood under the head, and set the engine down , taking the load off my jack. Blace said that we needed to make a skid for the engine, and as the Jacktown show was coming up, he would talk to the people there about obtaining some 12x12s to put under the Oil City Base. We left the building, with the engine resting on some 2x4s and the 5′ diameter flywheels!

Initial assessment
The next time I saw the engine, was at our monthly meeting. One of the members donated a 12×12 hand sawn beam, for mounting the engine on. The first order of business was to get the engine roughly where we wanted it, and place it on the timber. We again tried towing it with the old John Deere, but the engine would not budge. I ended up loosening the cross head way stay bolts, and then disconnecting the crank pin bearing and connecting rod big end, in order to allow the crankshaft to turn. We placed a roll around dolly under the head, and maneuvered the engine to where we wanted it. I knew that the engine had stopped with the piston nearly at top center. During the time between meetings, a few club members had removed the transfer port cover (See Picture 12), and the exhaust port ell from the side of the engine. (See Picture 13) The corroded cooling system piping was removed as well.

The news I got was not good. I was told that the transfer port was full of mud and debris, as well as was the exhaust port. I took a look into the transfer port and noted that there were 3 port bridges (used to support the rings while they traverse the port opening), and the piston, although covering the port, was not visible thru the dirt. I tried to feel whether the rear of the piston was near the port, but my fingers would not reach far enough into the transfer passage. (I later found out that the transfer passage contacts the engine cylinder at the very rear of the cylinder itself). I then removed as much debris as possible from the ports, between the bridges with a shop vacuum, and then filled the ports to the top of the bridges with a mixture of WD-40 and Liquid Wrench.

More assessment
At the next meeting, Blace Flatt and Steven Boutellette helped set the 12x12s under the engine. With 3 layers and a 2×8 piece of lumber, we finally had the entire engine off the floor. Steven and I tried turning the massive flywheels, but they only turned a little bit and stopped.. It was then discovered that the wheel rim has a slight bit of run-out on the inner rim, and the 12×12 spreader pieces would have to be cut, in order to clear the flywheel rim! Steven had them trimmed in short order, by using a 3′ cross cut saw, that the club has on display on the wall behind the engine! We then gave the crank a spin, and although stiff, it made a full revolution. The heavy gas engine flywheel was dead nuts straight, on the outside, but the inside edge looked like it had a wobble in it. As it turned out, the something had, at one time, run up against the inner side of the flywheel, thus actually peening the inner rim approximately ¼.” The steam engine wheel had some run out, but it appeared serviceable. 

Checking the crankshaft
I looked inside the transfer port opening, and noted that the WD-40/Liquid Wrench mixture had escaped from the port work on top of the piston. I refilled the port holes, and continued with some other work on the engine. I was afraid to try loosening the piston with the ‘spin the crank’ method, because I did not know how the piston was constructed, and exactly how bad it was stuck. In looking back, it’s a good thing I didn’t try it.

The crankshaft main bearing caps were removed , and the crankshaft itself was inspected. The crank looked pretty good , with only a few light pits where the crank had stopped under the oiling reservoirs on the main bearing caps. These reservoirs were dry, and at first I could not see how the oil got to the crankshaft. It turns out that most of the cotton wadding had rotted away long ago, being exposed to the elements. There was one good point to this though – there was a little of the degraded cotton in the bores of the bearing body, where the oil would have gone to the crankshaft. The degraded cotton prevented water from getting thru the passage, it blocked it so well, I had to use a ½” drill bit to remove it! (See Picture 14) The crank bearings were cleaned up with a fine flapper wheel, and the dust was blown off with compressed air. Some 50 weight oil was placed on the bearing, and then the crank was slowly rocked back and forth, and the oil wiped off, in order to remove any stray dirt and rust from the crankshaft surface. Once no more debris was noted, a final wipe down was done, and a liberal coating of the 50 Weight was given. The crank was then given a complete spin, and we watched the shaft for any debris to turn up. The oil flowed clean as a whistle, and after a good shove on the flywheels, the crank would spin for about 4 or 5 revolutions, before settling at the heavy point of the flywheel counterweight. (See Picture 15) I had had my wife save me all the cotton waste from our drier, and now put it to use. I filled the main bearing caps to within ¼” from the top of the bearing cap reservoirs, and soaked the lint with SAE 50 oil. It was noted that measurement of the crank throw yielded a stroke measurement of 17″! 

Cylinder head removal
I now decided to pull off the head, to see how bad the top of the cylinder was. I had bought a ¾” drive socket wrench set at the Hudson Valley auction, this year, and I was finally going to get a chance to use it! I used an 1¼” socket and a 2′ breaker bar to loosen the 9 ¾” threaded head nuts, with all but 3 coming off with little effort. Three of them decided to stay on the head studs, and the studs themselves came out of the block easily. After the nuts and 3 studs were removed, I pondered on how I was going to loosen the head from the cylinder. I did not want to use a screwdriver, or a chisel, as this would damage either surface, to loosen the head. I ended up using a large rubber mallet that I happened to have in my truck. After wailing on the head for about 5 minutes with the mallet, I noticed a 1/8″ crack in the top of the gasket space. I then began hitting the head on either side, making the force of the blows at about a 45 degree angle toward the front of the engine. The 1/8″ opening rapidly became ½”, and I stopped at that point, and tried to slide the head on the remaining studs. It slid easily, and I nearly slid it off the studs by myself! (See Picture 16) Thankfully I stopped it before it reached the end, as I was soon to find out, the head weighs approximately 75 pounds. If I had reached the end of the studs without being prepared for the weight, I might have lost a foot, or some toes, at least! I had another club member, Dick Haskins, help me to guide the head to the floor. (See Picture 17) I was really surprised when I looked at the head, and especially when I looked into the cylinder bore. The top of the head, and the top of the piston were in pristine condition! The piston had stopped approximately 1″ from TDC. The exposed cylinder wall was clean and shiny, which alleviated some of my fears about the engine being full of water, and mud. At this time, all the ¾ studs were removed from the cylinder, in order to make for easy work access.

A closer look at the piston
I noted that the top of the piston was nearly flat and that there was an approximately 1″ high deflector about ½ an inch from the outer edge of the piston top. (See Picture 18) I thought it was unusual for the deflector to go all the way around the piston, but you will find out why it was done, later in the article. There was a 1½” nut in the center of the piston head as well. I sprayed WD-40 and Liquid Wrench around the circumference of the piston, and again refilled the transfer ports, as the fluid was leaking out somewhere. I now removed the way guides that helped keep the crosshead way in place. If you look at the pictures carefully, on some you will see markings in soapstone – these were made so that the way guides and bearing caps could be re-installed properly, in the right orientation on the block. At this time I should explain how this engine operates, and how it is constructed, so as you can understand what I am talking about, further on.

The cross-breed explained
The Oil City/South Penn gas engine operates, and is constructed as follows: As I stated earlier, this engine started life as a steam engine. It was then converted to being an internal combustion engine, using the natural gas from the well, as fuel. The now replaced piston and cylinder are made entirely of cast iron. The actual cylinder is double ended. The charging (intake) end has a bolt pattern that matches the original steam cylinder’s mounting, to the engine’s bed frame assembly. An end cap is sandwiched between the cylinder itself and the engine bed frame. This cylinder end cap has a packing gland built into the center.. The end cap and the cylinder are both held in place against the block/base, with nine 5/8″ studs and nuts There is a deflector cast into the end cap, on the cylinder side, that helps direct the air/fuel mixture into the transfer passage, within the cylinder casting (it is pictured later). 

The piston is attached to a 1 ¾” steel shaft that passes thru the end cap, the packing gland, and then is attached to a yoke and a set of ways, as in steam engine practice. The piston rod is locked in place by means of a double wide 1 ¾” nut, cranked tight against the crosshead yoke. The yoke (or cross head), in turn is attached to the connecting rod, which in itself is attached to the crank throw. The rear of the piston is supported by the yoke and ways, which also contain the angular thrust developed by the crankshaft and connecting rod. The motion of the piston is strictly linear,, that is, it only travels up and down the bore. Angular forces generated on the power stroke (strong), and on the intake stroke (weak), work against the yoke and crankshaft. The crankshaft has Babbitt bearings on the mains, lubricated by oil galleys and felting. The con rod bearings are made of bronze, and uses the box and wedge type of retainer, at both ends. The con rod bearings are grease cup lubed. The cross head ways are lubricated by felt filled wells, on top of the way guides. SAE 50 oil and cup grease are used for lubrication of the slides and bearings.

On the compression stroke, the intake charge is drawn into the rear section of the cylinder. As the piston proceeds up the bore, the air must pass a flat poppet type valve, which also admits the gas charge. This is accomplished as follows: The poppet valve rests on a flat surface that is approximately 3 ½” in diameter . It has a shaft that is about 5/8″ in diameter, and is about 8″ long. The valve seat is a combined device, made of cast iron, that allows gas and air to enter the intake port at the same time. Air passes directly thru the seat assembly, from an inlet set to one side. This inlet is 2″ in diameter with a 2″x1 ½” reducer screwed into it. The purpose of the reducer is to make a slight restriction on the intake, like a venturi in a carburetor or a mixer. Around the perimeter of the intake seat, are a series of 3/16″ holes, drilled about 1 ¼” apart, that go to a separate passage, that is cast into the inlet. This passage is for gas, and it is supplied by a ¾” pipe that is connected. The poppet valve is held shut by means of gravity, and a light weight spring helps prevent chattering during operation. 

At the top of the compression stroke, the inlet valve closes, cutting off the flow of gas, and preventing backflow of the air/gas mixture back out the inlet. As the piston recedes in the bore, on the power stroke, the charge is compressed. When the piston uncovers the transfer port, as it travels down the bore, the compressed fuel-air charge then travels thru the transfer passage, goes thru the transfer port openings, and passes the top of the piston into the combustion chamber. The deflector on the piston directs the air/fuel mixture toward the combustion end of the cylinder.

Again as the piston rises, the transfer port and exhaust port are closed, and the charge is then now compressed within the combustion chamber. This compressed fuel – air mixture is then forced into the hot tube, where it is ignited. When the mixture ignites in the tube, a flame front travels back out the open end of the tube, and then ignites the rest of the mixture in the cylinder. Power generated by the expanding burning fuel pushes the piston down the bore on the power stroke, until the exhaust port is uncovered by the piston. At this point, the spent charge exits the cylinder, and then shortly after that, the next intake charge enters as the transfer port is again opened. The cycles then repeats, if all is well. The operation is the same as a Bessemer 2 stroke, and in some circles, I have heard that Bessemer actually had a license agreement with South Penn, to allow South Penn to build these types of engine components. Besides building the Half-Breed engine parts, South Penn actually built their own engines, into the early 1900s. The company apparently ceased operations in approximately 1910. 

The hot tube explained
For those of you who are not familiar with hot tube ignition, I will make a brief explanation. A hot tube ignition system works as follows: As the firing charge is compressed within the working cylinder, a small portion is forced into the body of the hot tube itself. The hot tube, typically, is a small diameter (¼” to 3/8″ in diameter) steel closed ended tube that is heated to incandescence, by a small external flame. This heated area can be from a dull red heat, to a bright yellow orange. As the fuel – air charge hits the red/orange heat spot on the hot tube, it ignites, sending a flame front back into the cylinder, which in turn ignites the rest of the charge within the power cylinder. Varying the heat, or location of the flame, will alter the timing, By raising the heat toward the closed end, you retard , and lowering toward the base, or adding more heat, you advance. Timing can never be retarded past TDC. This is due to the nature of the hot tube’s operation. The fuel-air mixture is compressed to its highest pressure, at TDC. At TDC, pressure is at its peak, and the mixture cannot be pushed any further up the tube. Therefore, the latest point of ignition occurs at TDC. It can be extremely advanced though, to the point that the mixture will fire almost immediately after the engine begins to compress the mixture. This super advanced timing can do real damage, if it is not remediated quickly, by either cooling the heating flame, or moving it toward the closed end of the tube.   Engine shutdown is accomplished by removing the flame altogether – this cools the hot tube below the fuel/air mixture ignition point, and the engine then coasts to a stop. 

Contact Andrew Mackey at 26 Mott Place, Rockaway, NJ 07866 • (973) 627-2392 • mackmotr@aol.com

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