Restoring an Oil City Boiler Works/South Penn cross-breed engine, Part 6

By Staff
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Andrew Mackey holding the two copper bearing covers he made.
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Mission accomplished! The finished Oil City Boiler Works/South Penn cross-breed engine, which was purchased and restored by the North Jersey Antique Engine and Machinery Club. Andrew Mackey and the rest of the club worked on the engine for more than a year to get the engine restored and running by the end of 2007.
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The hot tube assembly and decompression valve set up.
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Detail of holes in the hub of the steam flywheel on the engine.
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The main bearing covers in place on the engine.
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The new sign that was attached to the new engine enclosure.

Editor’s note: The following is the final part of a six-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. Read part 5.

Keeping the engine running
After the first start-up, the upper water piping was bearly warm. The way guides and the cross head were cool and well oiled. The main crank bearings were tight and cool to the touch, and the crosshead bearing, as well as the crank pin, were cool and well greased.

The piston oiler was another story. The drip sight was completely filled with oil and oil was seeping out the swing point on the drip setting needle valve. It turns out that I overfilled the oiler and the excess oil was blowing out. I had to take out the oil regulator needle valve and the sight glass drain in order to drain out the excess oil. Once drained to the point that the oiler upper oil level was seen in the oiler sight glass, the oil stopped dripping into the lower passages.

I lit the acetylene torch, and after a few minutes, turned on the propane supply valve on the tank. I pulled the engine up on its compression stroke with the decompression valve opened. Rocking the engine back to bottom dead center (BDC), I closed the valve. After a hard yank on the flywheel and a boom, the engine fired and kept going!

I quickly went to the piston oiler and set the drip rate to approximately 10 drops per minute. This may sound like a lot, but with a 10-1/2-inch bore and 17-inch stroke, there is a lot of swept cylinder area to cover besides the piston and rings! So far, the engine has not smoked or chucked liquid oil out of the exhaust, so the drip rate must be pretty close to the engines requirements.

A regular runner once again
The next day, another 20 pound propane tank was donated for firing the hot tube torch nozzle and the engine was ready to run on a regular basis. The engine was run daily for about 45 minutes several times a day for the rest of the 2007 New Jersey State Fair with only a few problems. While original resistance to turning the flywheels has lessened, compression has increased. Still, the starting procedure has been worked out so the engine can be started by one person fairly easily.

Trouble with the hot tube
We ran into a problem with the hot tube on the second day we ran the engine.

The mounting flange was severely rusted when we bought the engine and a bushing had to be fitted to the base in order to fit the new hot tube. The original tube was 1/2-inch iron pipe size (IPS) threaded, screwed directly into the base. It had failed (perhaps why the engine had been originally shutdown years ago) and the base was badly rusted where the 1/2 inch female threading was.

I had re-tapped the hole and installed a new 1/2- by 1/4-inch  IPS bushing in order to accommodate the new hot tube. Unfortunately, too much material was eroded from the base and compression was escaping from under the hot tube assembly through the worn threading. The solution was to bore the 1/2-inch hole out to 27/32 inch and re-tap the hole to 3/4 inch IPS and use a 3/4- by 1/4-inch bushing in its place. In order to do this repair the hot tube assembly had to be removed from the engine. The mounting gaskets also had to be replaced as they tore upon removal.

I made several modifications from the original set up. First, I set a tee in the base of the hot tube assembly. Then, a 1/2-inch IPS spark plug was installed in case of a future decision to convert this engine to spark ignition. This can be easily done by putting a wipe-spark timer on the right side of the engine attached to the crosshead way guide so that it makes contact with the crosshead itself as it travels through the guide. These engines were also retro-fitted with a WICO OC magneto and trip assembly if magneto ignition was preferred. Next, I fitted the decompression valve along with its related piping. This valve will assist future operators of the Oil City/South Penn engine to make starting easier.

Fit for the outdoors
I have also made several items to assist in having the engine outdoors.

First, I made two covers for the wicking pots on top of the crosshead ways. These I made from two 2-inch diameter copper pressure sweat caps for water piping. They were hammered into a slight cone shape and some of the material was removed from the sides in order to allow the caps to sit properly on the reservoirs.

I also made covers for the crankshaft mains, which required a lot of work! They both had to be made individually as the oil reservoirs and bearings are different sizes.

The first order of business was to obtain the copper for the covers themselves. I decided to make them out of the K wall thickness 4-inch copper pipe that was left over from making the accumulator tank. The left side bearing (steam flywheel side) is smaller than the right (gas flywheel side) so I decided to make that one first. I measured the top of the oil reservoir and the outside diameter came out to 5- by 7 inches with rounded ends (about a 2 inch radius).

I then cut a 7- by 9-inch window out of the 4-inch diameter copper pipe with my Milwaukee Sawzall. The piece of pipe was then heated with the Acetylene Turbo Torch until the entire piece was red-orange hot. It was then left to cool until all traces of the red heat were gone before the piece was dipped in water to cool it off. This annealed the copper (made it soft) so it could be hammered into shape around the bearing cap reservoir.

Hammering the 1/8-inch thick copper into shape was no mean feat! It took the better part of three hours to get the piece even close to the shape I wanted. The lip toward the rear of the engine could only overhang the bearing cap by 3/8 inch due to the fact that it was so close to the cap mount studs and nuts. The front overhang is 1 inch, with most of the lip bent inward at about a 100-degree angle from vertical of the cap cover. This made for a tight fit and the cover literally snaps into place.

Making the rounded ends was a real bear of a chore! Every time I thought I had it done I found the cap cover had moved, and I had to re-hammer the radius down again. Eventually, I finally managed to hit both ends at the same time with two hammers and that finally stopped the see-saw work.

The final touch was to saw off all the uneven edges and file smooth all the tool work. Once this was done, the entire cover was polished with Never Dull, and then the cap cover was installed on the bearing cap. Start to finish, about six hours were spent on this project and I had an audience of fair goers nearly the whole time.

Making the cover for the gas flywheel side took longer for several reasons. First, this side has a bigger bearing as it is the “working” side of the engine. It has the bigger, heavier flywheel and the clutch attached, and the power is taken off the crankshaft on this side. This bearing cap reservoir measures 6- by 11 inches and needed a piece of copper 8- by 13 inches in order to fabricate. This plate was also cut out of the leftover copper pipe and heated red-orange as well.

After the copper plate had cooled, I bent the 1/2-inch lip on the bolt side with a vise and a big wooden mallet. All the banging sure brought a crowd! I then formed the opposite edge by using a hammer against the copper while the partially formed lid was in place on the bearing cap. Trying to get that 100-degree angled edge was more difficult than on the first one due to the longer edge and the slightly different shape of the bearing cap itself.

Making the rounded ends proved to be a real challenge on this side. As the bearing cap was larger, the rounded end was not the continuous edge as it was on the other side. This made it hard to hammer the copper to conform to the shape of the reservoir, especially on the crank throw side (inside). The crank throw itself only has about 1/4-inch clearance between the bearing cap and the side of the throw of the crankshaft. Getting the 1/8-inch thick cover to grip the inside edge of the bearing cap was a necessity and the copper wasn’t making it easy! I had to quit for the night as I had to re-heat the cover in order to soften the metal again (it hardens as you hammer it). A lot of the engine club building visitors were disappointed that I didn’t finish the cap, but, as I explained to them, you can only hammer the material so long before the metal fatigues and breaks. As I had been hammering on this particular part for over 5 hours, and it was pretty warm to the touch, I thought it was a good time to quit before I fractured the piece and would have to start over.

Patience rules in this project
The next evening, I brought in a replacement “B” tank, and switched over the regulator and accessories. I lit it with a loud BOOM that elicited a scream from somewhere in the crowd and proceeded to heat the copper cover. With a full tank of gas and full pressure the Turbo Tip had the cap bright orange within several minutes.

Once the cover-to-be was cooled, I took it to the bearing cap and tried the same technique as I had used on the other cover – that is, hammering on both ends at the same time. Because of the longer length on this side, it did not work as well. The ends tightened up fine but the hammering also caused the long sides of the cover to deflect outwards about 1/2 inch from the iron body of the bearing cap. If I re-hammered the sides then the ends would fold back out. Back and forth this went three times and I was getting frustrated.

Eventually, an old gent that was observing the whole operation said to me, “Why don’t you get a furniture clamp and clamp the sides while you hammer the ends back in place?” By now, I was really wired and was about to make a reply I surely would regret later when I realized the man was right! I had to restrain the lips at the sides of the cap while the ends were being formed. I didn’t have a furniture clamp, but I did have two large C clamps in the engine building.

The sides of the cover were again hammered back in place and the two clamps were installed, about 3 inches apart. On the first hammer blow to the short ends both clamps flew off the cap and went about 5 feet in the air. They almost cleared the fence around the engine!

In looking at the cover and the bearing cap, I noticed that this cap does not have straight sides like the steam side cap. This bearing cap is thicker, I believe, to take the heavier load on this side of the engine. I then found several thin pieces of wood and clamped them between the cap and the clamps in the hope that the clamps would not slip off the copper. The idea worked perfectly and the copper cover stayed in place and did not deform as the ends were beaten into shape. In fact, it worked too well! I had to pry the new cover off the cap so I could trim the excess material from the lower edges and then polish the metal. A few taps on the outboard end with the clamps removed had the copper cover fitting perfectly. This cover now snaps into place and stays put.

Some finishing touches
Some minor things still needed to be done before we could call this restoration complete.

First, the two 3/4-inch vents needed to have screens installed to keep out critters, and the over flow piping needed to be soldered.

Next, the boiler drain valve under the engine cylinder had to be replaced with a ball-type valve. Rust and scale, left inside the cylinder, were falling into the vertical plumbing assembly and jamming the boiler drain, but a full-port ball valve should alleviate that problem.

We also replaced the steel 1-inch plugs in the openings of the water cooling reservoir with brass. We installed a thermometer in the tank as well. As a last thing to do, the exhaust ell was re-installed, and a 7-foot-long piece of 4-inch aluminum pipe was placed on the riser on the ell. Club president Blace Flatt found a nice chrome exhaust tip from a tractor trailer,and we installed it on the aluminum pipe. It really looks neat!

The project will finally be complete when we are able to build a shed around the engine to keep it out of the elements during the winter and when the engine is idle.

The last notes on the engine restoration have to do with the engine balancing. Many people have commented on the fact that the steam engine flywheel has no counterweight, as on the gas engine flywheel. The fact is the steam engine was balanced with “old” technology (for the time)  and the gas engine wheel was balanced with the “new” format (counterbalance). In fact, the steam wheel is balanced! The hub of this flywheel is cored out so that nearly 1/2 of the hub is hollowed out! Due to the fact that the rim is relatively light weight, the builders did not want a lot of centrifugal force working on the rim of the wheel. To make up the weight loss needed to balance the engine and keep the weight to a minimum, the weight was removed at the hub. This must have been some casting job as the spokes actually have the holes cast around them!

You can now see the engine in person at its permanent setting at the Sussex County Farm and Horse Show Grounds in Augusta N.J.

Special thanks
To end this tale, I have several credits to assign.

First, to Tom Schoolcraft. His advice and help with getting the engine assembled and running was invaluable. Second thanks goes to Harry Mathews and his SmokStak website. The help from the members on the “Stak” was also a necessity. A special thanks also to the Oil Field Engine Society Forum is in order too! Next, is a big thanks to my son, John Mackey. John was a great help fetching parts and filming the start-up video, which you can watch on YouTube.

Last but not least, a BIG THANKS to all the North Jersey Antique Engine Machine Club members who helped with this restoration. Without their help and support this project would not even have been started!

Contact Andrew Mackey at 26 Mott Pl., Rockaway, NJ 07866 • (973) 627-2392 •

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