Arizona Railway Museum - Plymouth #1 Project Page

Complete repair and ongoing maintenance of locomotive for use as museum's main motive power. The gas-mechanical switch engine is "right sized" for moving the other cars on display.

Built in March of 1943 as serial number 4463 for the U.S. Army. Donated by Railroad Builders Inc.. in 1988. Model ML-8 weighs 62,000 pounds on 33 inch drivers. Sold to the M. Lummis Company, then to Pacific Railroad Contractors , then to Railroad Builders of Mira Loma California. The locomotive has been restored to operating condition and cosmetic work is currently underway.

This Log Book is being started after an extended period of repair work performed on the Plymouth. Two major problems were addressed:

1) A large hole developed in one cylinder wall. Cylinder was bored and re-sleeved. The corresponding head also developed cracks. Head was repaired.

2) A broken valve part destroyed the compressor piston. New valve parts and a piston were fabricated and installed.

The following organizations have made donations of materials, labor, and/or monies to aid in this restoration project:

The Conrader Company refurbished the Plymouth’s air compressor unloader pilot valve at no charge. When that did not correct the problem, they swapped their historical display unit for the one in the locomotive (again, at no charge). That’s mighty fine customer service, 62 years after the sale!

July 12, 2008
Re-assembled the components of the air compressor, with all new parts fitting well. Started the engine and got up to 110 PSI on the main reservoir – compressor is fixed! Ran the locomotive up and down the track a few times – everything ok. Should probably check the tightness of the compressor’s valve hold-downs before operating again.

June 21, 2008
Located replacement copper sealing rings for the intake and exhaust valves. Known as ‘copper crush port gaskets’, they are made of copper wrapped around an asbestos-like material. Found the exact size needed at www.restorationstuff.com, part number GAS034, 2-3/4” ID x 3” OD.

Located replacements for all nuts, washers and set-screws needed to re-assemble the compressor. Most were badly rusted and/or had damaged threads.

June 14, 2008
Located a replacement leather cup washer for the unloader piston: not an easy item to find! Part is for a Pista-brand bicycle floor pump, part number 73.1. After soaking the washer in neetsfoot oil, it appears it will work okay.

Repaired the broken section of the exhaust valve seat, using Devcon steel putty.

June 07, 2008
Opened cover plate on air compressor – what a mess! Found five problems that all likely contribute to the low air pressure. In fact, it is amazing that we got as much as 35 PSI from the system.

1) The valve plate and springs on the exhaust valve are broken. Fortunately, replacements are on-hand.

2) The leather cup washer on the unloader-piston is completely worn away. A new one will have to be obtained or fabricated.

3) The copper sealing ring for the exhaust valve assembly is nearly gone. A new one will have to be fabricated.

4) A small section of the valve seat on the exhaust valve assembly is broken away. Being a cast-iron part, repair may be difficult.

5) The bolt holding together the exhaust valve assembly is worn and needs replacement. The locknut on the current bolt is too short to get a good wrench grip on it. A taller nut or standoff will be used.

Additionally, it is suspected that the compressor valves may have been improperly re-assembled on the last rebuild. The valve assembly hold-down cages may not have been fully tightened, allowing the valve assemblies to bounce up and down, possibly contributing to some of the above problems. This will be addressed when re-assembling the valves.

May 03, 2008
Started the engine, but observed that main reservoir would not go over 35 PSI. Used the locomotive to pull the Baldwin away from the other equipment.

Started the engine again to return it to its parking spot – still observing low air pressure. Will need to investigate that – the compressor probably needs attention again.

April 05, 2008
Started the engine and exercised the locomotive up and down the track. All systems okay.

March 15, 2008
Replaced the ignition battery w/Energizer #56-550E, Group Size 56. Also replaced the entire negative battery cable (24” - 4 GA) and the positive battery clamp. Engine starts fine now, and ran the locomotive up and down the tracks.

March 08, 2008
Removed the dead ignition battery, and cleaned-up the battery tray.

March 01, 2008
Moved the Baldwin and The Federal after arrival of the new dome car. Jump started the still-dead ignition battery to get it started.

February 23, 2008
Started the engine and exercised the locomotive up & down the track. Jump started the still-dead ignition battery to get it started.

January 27, 2008
On attempting to start the engine, it was discovered that the ignition battery was dead. A quick hook-up of the battery charger got it started. Despite the rain, performed several yard-length runs with two cabooses filled with museum members.

January 26, 2008
Moved locomotive and cabooses in preparation for tomorrow’s Annual Membership Meeting.

January 19, 2008
Moved the accumulated ‘junk’ from the cab to either a trash can or the “motive power storage locker”, aka the concrete phone booth. Also vacuumed the cab’s interior in preparation for upcoming Membership Meeting. Removed the old acrylic protective covers on both headlights: both were quite clouded with age, and were no longer required in our now more-secure location.

September 15, 2007
Replaced both starting batteries: engine now starts fine. Added 1 gallon water to radiator. Exercised engine in yard.

August 08, 2007
Added 50 gallons fuel, plus octane booster and fuel stabilizer. Batteries required charging before starting – they are getting very weak now.

Performed switching to move bulkhead flatcar to track 6 for loading of miscellaneous junk.

July 14, 2007
Good news today! Charged each of the two starting batteries for about 1-1/2 hours each (using the 40-amp setting on the charger), and the engine started easily. Ran the engine for about ½ hour.

July 07, 2007
Greased water pump bearings (4 places).

Attempted to start the engine, but the batteries were very weak. Ran out of time to find the battery charger or investigate further. (Batteries are several years old and likely need replacement.)

June 23, 2007
Topped-off batteries with distilled water.

Topped-off radiator with plain water.

June 02, 2007
Drained crankcase and replaced with 20W-50 oil (40 qts).

Drained oil filter canisters – considerable water and sludge had accumulated. Draining these canisters should be added to the list of periodic maintenance tasks.

Replaced oil filters (2) with NAPA 1503.

Replaced fuel filter with NAPA 4347.

Started engine, and observed higher oil pressure than before (that’s a good thing).

May 26, 2007
Replaced missing screw/nut on window frame, and tightened all others (all were loose).

April 30, 2007
Performed extensive switching to rearrange display equipment.

The radiator boiled-over about half way through the switching work. After waiting for the engine to cool, switching resumed at a somewhat slower pace to avoid overheating.

April 21, 2007
Fired up the engine and gave some cab rides for some family members of an old museum friend. Received a $90 donation for the Plymouth project.

April 14, 2007
Cleaned corrosion from the ignition battery terminals and the adjacent electrical bulkhead.

Replaced the wires from the battery charger.

Replaced the wires from the ignition battery to the ignition relay. Old wires were too short to allow the battery to sit straight in the tray.

Placed wood strips between and around each of the three batteries. This will keep the batteries safely spaced from each other, and prevent the batteries from shifting in the tray.

April 07, 2007
Completed painting of the inside of the engine compartment doors. Added 1/16” thick closed-cell foam gasket around the door edges to reduce vibration noise caused by the doors rattling against the hood.

April 06, 2007
Washed the inside of the engine compartment doors in preparation for final painting.

February 05, 2007
Added 5-quarts of lube oil, approx ½ gallon of battery water, and 1-1/2 gallons to radiator water.

August 21, 2006
Used the locomotive to re-arrange some of the cars for better display purposes (specifically, putting all the cabooses together).

Parked the Plymouth in its designated spot (near the electrical outlet for the battery charger).

August 12, 2006
Added 2 quarts of oil to crankcase. Numerous small leaks are beginning to add up, especially with all the hard running lately.

The final trip to Tumbleweed was made, with the Plymouth in tow behind the string of passenger cars. Locomotive was running (but not under power) for the trip, so full advantage was taken of the opportunity to celebrate our final departure with much ringing of the bell, blowing of the horn and sounding of the whistle. Upon arrival at the new location, the locomotive pushed the entire string of cars into the yard. New home at last!

Two speeders followed behind on this last trip, which made for quite a sight on the rails!

August 11, 2006
Used the locomotive to re-arrange and set-up a string of cars in preparation for the last load to be taken to Tumbleweed.

August 09, 2006
Used the locomotive to re-arrange and set-up a string of cars in preparation for the next-to-last load to be taken to Tumbleweed.

August 07, 2006
Used the locomotive to re-arrange and set-up a string of cars in preparation for the next load to be taken to Tumbleweed.

August 05, 2006
Added 4 quarts of 30W oil to crankcase, plus 2 bottles of STP Oil Treatment.

Checked oil in transmission (2 separate compartments). Both appeared to be full (in fact, somewhat over-full).

Moved cars to allow speeders to be moved from end of track #4.

July 30, 2006
Added 2 quarts of 30W oil to engine crankcase. Used the last of the oil on-hand: still needs more oil.

Moved cars around to set-up museum’s calendar photo shoot: three platform passenger cars in a row.

July 29, 2006
Moved cars around to help with removal of utilities along Track #1.

Added 50 gallons fuel, octane booster, and fuel stabilizer. A new gasket for the M-3 Feed Valve was received.

Pulled out a string of five cars to facilitate adding diesel fuel to the dining car.

Fuel low – added about 4 gallons from Emergency Can, plus another 5 gallons purchased. Must fill tank before next operating session.

Performed more switching to put out three tank cars and a caboose, for the third load moving to Tumbleweed Park. Performed set-n-release brake tests on the outgoing cars.

A new gasket for the M-3 Feed Valve could not be obtained in time, so a temporary fix was done with Loctite 5699 Silicon Gasket Maker. As the old gasket had only a small rip in it, this seems to be holding ok. A new gasket is on order (Wabtec #81006).

Used the Plymouth to move the steam engine for the first time in several years. It wasn't too hard to get it started and moving down the straight track, but the Plymouth lost traction in the middle of the tight curve on Track 3. With much sanding, throttle and clutch fiddling, spinning of wheels and stalling of engine, the Plymouth finally got the steam engine moving and past the curve. Whew!

Performed extensive switching to reposition equipment onto track #4, for the second load moving to Tumbleweed Park.

Performed set-n-release brake tests on the outgoing cars. Shortly afterward, the cover gasket on Westinghouse M-3 Feed Valve blew (part of the brake system), causing a major air leak. This must be fixed before the next operating session.

Performed switching for the Jane Marie and the Vista Canyon, returning from a charter trip on the Apache Railway.

Re-installed engine compartment door latches. Despite valiant efforts, painting of engine compartment doors is still not complete. Weather has become too hot, so painting will resume in a few months.

Obtained 1/16” thick x ½” wide foam gasket for use around the door edges. This will prevent metal-to-metal rubbing and damage to the painted surfaces.

Checked and re-filled batteries, and checked and re-filled radiator.

More brush painting of engine compartment doors. Painted rods for the door latches.

More brush painting of engine compartment doors. Completed first coat on all areas, but a second coat is required.

Applied the final gray paint (Rustoleum Gloss Smoke Grey) with a roller to the flat areas of the inside of the engine compartment doors. Two coats were required.

Finally removed the two stubborn latches on the engine compartment doors. Cleaned the latches, reconditioned the damaged threads, and found new stainless hardware for the rod connections. Sanded the old paint and rust from the latch rods, and applied a primer coat.

Used the locomotive to swap positions of the Baldwin and the Federal, to facilitate air conditioner work on the car.

Applied the primer coat with a roller to the flat areas of the inside of the engine compartment doors (Rustoleum Primer for Rusty Metal).

Finished preparing doors for painting. Applied degreaser, and washed and rinsed doors to prepare for painting.

Scraped, wire brushed and sanded the inside of the engine compartment doors to remove rust and loose paint in preparation for painting. Removed all the door latch rods, and latches from the fireman’s side. The latches on the engineer’s side proved stubborn, to be left for another day.

Used the locomotive to put out the Jane Marie and Vista Canyon for pick up by the UP, for the purpose of a charter trip on the Arizona Eastern RR.

“Boeing Day” volunteer assisted with scrapping paint and rust from the inside top of the engine compartment. Thanks Carlos!

Used the locomotive to pull out the Baldwin for starting. Had a visit from Ken Keyer (BNSF Engineer) for a lesson in the use of the E6 Train Brake Valve.

Pushed Amtrak-certified cars back together again after completion of annual Amtrak inspection.

Separated Amtrak-certified cars in preparation for their annual Amtrak inspection. Pulling 7 cars at once was tricky!

Topped-off water in batteries. Pulled the Desert Valley out to the crossing for the Chick-Fil-A calendar photo shoot.

Performed extensive switching to position flatcar in front of C45 crane. This will facilitate lowering the crane’s boom in preparation for the move to Tumbleweed.

Repaired air line for the compressor unloader valve. It appeared that the flare on the copper tubing was not sufficient, and the tubing worked loose. Started engine and verified proper operation of the compressor.

Moved Plymouth and Baldwin out for display for the Annual Membership Meeting. Air line for compressor unloader valve popped out of the fitting on the compressor end.

Moved Plymouth out into the yard for washing, in preparation for next day’s meeting.

Moved Diablo Canyon out into the yard for more painting work.

Moved Baldwin out into the yard for washing.

Moved Diablo Canyon out into the yard for painting of the ends and trucks.

Moved Baldwin out into the yard for starting.

Completed new ARM lettering for engine hood.

Replaced and re-mounted the two remaining diodes in the battery charging system. Repaired the cracked insulation on the battery cables with several layers of electrical tape.

Moved radio’s power take-off from starting battery #1, to switched ignition circuit. This avoids the possibility of leaving the radio ’on’ when the loco is not in use.

Cleaned the fuse clips for cab voltmeter circuit (again). Poor contact continues to be a problem.

Added 2 quarts oil to crankcase.

With expert help from Ron Schofield, the cause of the negative generator voltage is determined to be bad insulation on the isolation diode for the ignition battery. The diode was replaced and the thin mica washer insulators were replaced with nylon shoulder washers. The generator output is now positive, and the ammeter is indicating charging current. The battery charger indicator does not light when the engine is running.

That diode had tested bad in previous troubleshooting, but was not felt to be the cause of the immediate problem. Nevertheless, replacing the diode and its insulator fixed the problem, even though the exact reason is still a mystery. If the diode had been hard-shorted to the chassis, it would have drained the ignition battery (or much worse). The mounting of the other two diodes will be improved in a similar fashion.

Moved Vista Canyon out to the branchline for pick-up by the UP.

Continued (unsuccessfully) to troubleshoot cause of negative output from generator.

Rearranged several cars to bring out the Vista Canyon for the San Diego charter trip. Ignition battery voltage slowly dropped as operation continued, but remained at an acceptable level.

Reinstalled the battery charger so that the batteries would recharge before the next use. With the generator putting out negative voltage, the engine is running strictly off the batteries, and the batteries are not recharging.

Removed battery charger to check components. Replaced unsupported axial-lead filter capacitor with a bracket-mounted unit, replaced the bulb, and added a 1N4006 diode in series with the output to prevent generator backfeed. Cleaned and painted the charger enclosure.

Observation – battery charger lamp is in series with the output, and is therefore a charging indicator, not just a power indicator. If the bulb is burned out, no charging will occur.

Observation – measuring the voltage at the regulator output yields odd results: approx. 13 V positive with engine off, but then approx. 14 volts negative with engine running.

Removed non-operating roof-mounted beacon. Replaced one burned out bulb, and oiled rotating mechanism. Unfortunately, we lacked the proper tools to do a thorough disassembly. Reinstalled the beacon, and it seems to work better. Yellow plastic needs replacing.

Completed wire tracing and drawing schematics. Topped-off water in batteries. Fixed non-operating position on cab voltmeter selector switch (contacts on 3A fuse holder were corroded). Fuseholder will require replacement at some time. Found and reattached cover plate on left hand starter.

Cleaned sixteen sparkplugs using abrasive grit. All plugs appeared uniformly covered with a thin layer of carbon. Some from the left bank of cylinders smelled of fuel (not documented which ones).

Continued with tracing of wiring.

Performed switching to place TC&GB flatcar in its final display location. Pulled the Baldwin out for its monthly starting.

October 28, 2005

TC&GB boxcar and flatcar arrived via truck, and used Plymouth to move cars into temporary position.

October 22, 2005

Pushed cars adjacent to the Vista Canyon back together, after completion of Amtrak inspection.

Began process of tracing and documenting electrical systems. Systems for charging, starting, and ignition have been documented, leaving only lighting and cab accessories to be done

October 20, 2005

Moved adjacent cars away from the Vista Canyon to allow access for Annual Amtrak Inspection.

October 19, 2005

Moved winter-visitor private car Federal into the yard, and rearranged other equipment to accommodate the Federal’s power and vestibule requirements.

Observed that the battery charger’s pilot light glows very brightly when the engine is running. This could explain why the bulb doesn’t last long. Why is this happening – bad voltage regulator?

October 15, 2005

Engine wouldn’t crank. After checking and cleaning battery cable connections (some of which need further work), it was noticed that the water was very low in the two starting batteries. With the addition of distilled water and some charging, the engine finally cranked and started. Thou shalt check battery water more often! Bad mechanic!

Filled tank with approx. 40 gallons fuel, and added fuel stabilizer. Still needs octane booster.

Moved Baldwin out for its monthly starting.

October 01, 2005

Continued with scrapping more gunk off the transmission.

September 24, 2005

Installed four new crankcase ventilators. Custom-made ventilator consists of a cylinder made of perforated steel, with several layers of aluminum mesh would inside. Entire assembly is powder-painted black –very nice!

Replaced bulb in battery charger pilot light.

September 17, 2005

Began process of scrapping gunk off the engine, starting at the transmission. This is the start of a very long process to clean up and eventually paint the engine.

Removed one of the crankcase ventilators, to design a replacement for the one (of four) that is missing. Due to the poor condition of the three remaining ventilators, all four will likely be replaced.

September 10, 2005

Used Plymouth to pull the Baldwin into the center of the yard lead, in preparation for starting the diesel.

Adjusted clutch linkage and transmission brake. Clutch pedal was active at the very top of its travel – adjusting the linkage moved the action down to the middle of the pedal travel. Transmission brake (device that stops the transmission from spinning when shifting) was apparently inoperative, making shifting difficult. Adjusting the brake now stops the transmission at the bottom of the clutch pedal travel. Overall, operating the clutch and shifting the transmission is now easier.

Performed more switching of cars upon arrival of Jane Marie. Due to high ambient temperature (110 + degrees F) and heavy cuts of cars being handled, radiator boiled over after about 1-1/2 hours. Shut down engine, with switching work not finished.

Moved locomotive to north end in preparation for arrival of Jane Marie. Andy Chinn’s turn at the throttle, with a few runs back n’ forth.

Performed extensive switching of cars due to the arrival of the new dining car. (2 hours plus). Practiced use of sander when pulling heavy cuts of cars.

Engine ran ok, although oil pressure was very low (red zone) by the end of the work. With ample time to observe the air compressor controller, it did (without intervention) regulate the pressure between 75 and 130 PSI. This indicates that it is working, and that it merely needs adjustment to raise the low-side cut-off.

Used Plymouth to pull the Baldwin into the center of the yard lead, in preparation for starting the diesel.

Added to fuel tank:
(2) - 15 fl. oz. Bottles of “Octane Booster”, Lucas Oil Products, www.lucasoil.com
(1) – 16 fl. Oz. Bottle of “Sta-bil Fuel Stabilizer”, Gold Eagle Co., www.goldeagle.com

Added cork gasket around mounting flange of fuel filler pipe. (Fuel was sloshing out when tank is full.)

Replaced 3-3/4” ID rubber hose between air cleaner and carburetor. Moved locomotive to north end of yard in preparation for arrival of dining car.

Moved several cars (and the Baldwin!) in preparation for departure of Vista Canyon to NRHS Convention in Portland OR.

Despite adding more grease to the axle bearings, there was still no visible squeeze-out of grease around the bearings. With almost two cartridges of grease applied to the four axle bearings, this seems to be the proverbial bottomless pit. Where is it all going?

Lifted panel on cab floor to gain access to gear ratio selection lever and linkages. Found and lubricated several more zirks. Some of the moving parts lacked zirks or oil cups, which was surprising. Lacking any other means to lubricate these parts, oil was dribbled on the joints.

Received adjustment instructions from Conrader Co., for the purpose of calibrating the air compressor control valve.

Put 45 gallons of gasoline in fuel tank. Ron suggested we also add a fuel preservative and an octane booster.

Located and documented many lubrication points: 12 zirk’s and 14 oil or grease cups. Judging from the amount of dirt obscuring the zirks and cups, some of them had not been touched in a very long time. There are probably still more lube points to be found. List of lubrication points (and date lubricated) will aid in the preventative maintenance of the locomotive.

Replaced faulty coil wire on right-side ignition. Fixed leak near fuel shut-off valve.

Received, installed and tested ‘new’ compressor valve. Unit properly shuts off at 125 PSI, but does not reset properly (pressure dropped below 70 PSI, at which point we manually reset the valve to preserve air brake operation). Will contact Conrader again for advice: this valve was reportedly factory-set for 100-125 PSI operation.

Changed crankcase to straight 30W oil, with 3 quarts of an STP-equivalent. Initial oil-pressure reading is now 5 PSI higher than before. Did not get engine hot enough to judge loss of oil pressure at high temperature.

Removed faulty hose between air breather and carburetor. Ordered new 3-3/4” hose.

Contacted Conrader Co. regarding faulty compressor control valve. They are sending their historic display unit to swap with our valve. What customer service!

Engine wouldn’t start (cranked okay but no ignition). Traced problem to defective solder connection on ‘ignition’ fuse holder on cab panel. Repaired connection and engine started easily. Moved engine to opposite end of yard in preparation for arrival of car.

Replaced battery charger pilot lamp (used bulb #89). No coolant leaks observed around radiator.

Installed second new distributor. Thanks to John Mueller for doing the machining work for the distributor modification. Engine started easily, and ignition timing was fine-tuned. Engine ran better still.

Observed starter relay sticking. Rebuilt both relays: reattached contact plate to plunger on one relay, and refurbished contacts on both.

Compressor controller (rebuilt by Conrader Corp.) works better than before, but rather than the range of 100 to 125 PSI as requested, it trips out at 130 PSI, and only reluctantly cuts back in at < 70 lbs. Controller can be cut back in manually if necessary. Will contact Conrader to see if we can adjust this range.

After running the locomotive up and down the track several times, coolant was observed leaking from the radiator. Suspect this was just expansion overflow from the cap, as this was the first time engine had gotten very hot since filling with antifreeze.

Installed quick-release on whistle pipe, to facilitate quick installation and removal of whistle (for security purposes). However, this presented two problems: 1) whistle is now mounted higher, and the actuator rope is at the wrong angle, and 2) whistle can swivel on quick release, and engine vibration will likely cause it to revolve.

The quick-release is a good idea, but still has some details to be worked out.

Ron Scofield located a suitable distributor (for a 1972 Chevrolet ½-ton pick-up w/350 cu in V8, to be exact). He modified the drive end of the unit, and it fit perfectly to the Leroi engine. With just one distributor firing only one plug per cylinder, the engine started eagerly and ran better than it has in quite a while. Not bad for only half the ignition system!

Checked all pushrods and adjusted for proper clearance.

Ron will proceed with the purchase and modification of a second distributor. With both distributors installed and firing both plugs on each cylinder, the final engine timing can be dialed-in.

Cleaned battery terminals, refilled batteries with distilled water (Thanks, Charlie).

Prepared drawings for distributor wiring and cylinder numbering. Drawings were a great aid in thinking about the complicated ignition, and will be used to document the final version.

Verified firing order shown in Leroi manual. Found more loose pushrod ends on cylinders 1 – 2.

Distributors have dual points, a four-lobe cam, and a two-ended rotor. Firing occurs on alternating points, (4 lobes x 2 points = 8 hits). Concluded, after much experimentation, adjustment, etc. that distributor caps are no good. Since replacement caps are not available (?), a search for new distributors will commence. Criteria: adaptable to existing mounting and drive on engine, 8-cylinder with single points and 8-lobe cam.

Organized Plymouth and Leroi documents received from George Holt. “Originals” will be kept in museum files, and where pertinent, copies will be made for shop use.

Installed reconditioned air compressor unloader pilot valve. Testing will have to wait until engine is running properly.

Traced sparkplug wiring and made drawing of current configuration. Confirmed that left distributor controls head sparkplugs (outside of ‘V’), and that right distributor controls block sparkplugs (inside of ‘V’). However, neither distributor was wired in the published firing order of the engine, nor were the two distributors wired the same as each other.

Removed valve cover on cylinders 3R/4R, and discovered that the cupped fittings on both pushrod ends had become detached on cylinder 3R (and therefore the valves on that cylinder were inoperative). No idea how this could have happened – reattached fittings and adjusted valves.

Observations from today lead to amazement that the engine ever ran at all. Before any rewiring of the distributors commences, the firing order will be verified experimentally (rather than trusting the Leroi manual).

Began process of analyzing ignition system. All four coils and points seem to work okay, but serious degradation of the distributor caps was observed (this is not new information – caps have been in bad shape for some time, with previous repairs attempted using epoxy potting compound).

During this process, the engine timing was disturbed to the point that the engine now won’t start.

Small amount of water drained from crankcase ran clear (not green with antifreeze!) This indicates that crankcase water is due to condensation only, and is not caused by a coolant leak.

Cleaned 16 sparkplugs with pneumatic abrasive device. On five cylinders, both plugs of each cylinder were dry, with only a moderate amount of carbon build-up. However, on the three other cylinders, both sparkplugs of each cylinder were wet with fuel, with very little carbon. This would indicate that those three cylinders have been firing very little if at all. These ‘bad’ cylinders were 3L, 3R, and 4R.

NOTE: this logbook conforms to the Leroi Engine Manual’s convention of looking from the gear-end (front) of the engine to identify left/right, with cylinder numbering starting from the front.

Inspected oil-bath air cleaner. No oil!

Drained plain water from radiator, and replaced with 30% antifreeze solution (previously drained from Baldwin).

Demonstrated locomotive: started and ran up and down the track, with cab rides for the few members willing to withstand the backfiring.

"George E. Holt" lettering applied to both cab sides. A nice tribute to a great guy.

Decision made (with Bart) to letter cab side with "George E. Holt", to honor long-time curator of the Plymouth.

Discovered missing bolt on compressor exhaust valve (again!) Replaced bolt, used Loctite and peened end of bolt. If bolt loosens again, fastening of valve must be changed.

Started and ran twenty minutes to verify compressor repair. Experimented with lever on carburetor (disconnected from governor long ago). In one position (away from carburetor), engine ran smoothly. The other position (towards carburetor) caused immediate backfiring. This lever in the wrong position may have caused the extensive backfiring observed on Dec 31. Need to fasten lever in correct position.

Removed air compressor unloader pilot valve for refurbishing. Located and contacted manufacturer R. Conrader Co. of Erie PA (since 1925!). Manufacturer offered to refurbish and calibrate valve at no charge. Valve sent to Conrader 1-19, via UPS.

Started and ran about 2 hours: backfiring only at first when cold. Performed switching, but did not complete job due to compressor failing again.

Performed extensive switching for several hours. Baldwin also in use for switching – another museum first! Accomplished major portion of plan to rearrange rolling stock.

Engine started easily, but continued to backfire even after warm-up. (A foggy morning, with much dew.) Backfiring was most pronounced at idle, especially when compressor was manually unloaded. Very little backfiring occurred during running. Good power was available from the locomotive.

Oil pressure dropped as operation continued. Two bottles of STP Oil Treatment were added, but little change was observed in pressure gauge reading. Crankcase full. Gauge is defective, sender line is clogged, or…

Started engine: easy start with fairly smooth running after initial warm-up. Tested air pressure pop-off valve: valve operated reliably at approx. 130 PSI.

Identified main air pressure regulator in cab. Operated regulator manually by lifting the lever: compressor unloaded properly, identified by a change in the sound of the engine, and a drop in air pressure. Regulator is either set above 130 PSI (above pop-off valve) or tripping mechanism is inoperative.

Cleaned and lubricated air pressure pop-off valve located on pipe from compressor to main reservoir. (Thanks, Bart.)

Bolt securing exhaust valve “sandwich” had worked loose, and was no where to be found (presumably was shot out the exhaust port, and is currently residing in main pipe or reservoir). Replaced bolt and secured with Loctite.

Pressure tested system from stationary air supply, but still could not raise pressure in main reservoir. Cleaned burrs from copper seating washer on exhaust valve, and tightened set-screws on intake and exhaust valve hold-downs.

Retested system and main reservoir began holding pressure. Started engine and pressure slowly climbed to 75-80 PSI, and held there. Ran locomotive up and down the track a few times, but then pressure began to climb again, reaching 145 PSI when engine was shut down. Unknown if pressure would have gone higher given more time. Pressure release on air system did not blow.

Engine start was not immediate, and required extensive cranking. After starting, it ran poorly, acting as if only a few cylinders were firing. Performance smoothed out after a few minutes.

Added 55 gallons fuel. Started very easily, ran smoother than before, and only backfired a few times. Air pressure gained slowly to an acceptable level.

Performed minor switching to push a few cars together. When work was almost complete, air pressure went to zero. Attempted to recharge from the stationary compressor, but could only reach 28 lbs. Limped back to home base with great caution and the hand brake.

After shutting down, again attempted to recharge air. Air rushing inside the compressor could be heard, and air exiting the compressor intake could be felt. One or more of the valves are probably broken or stuck.

Locomotive moved under its own power for the first time in nearly two years! This date marks the first time in the museum’s history that the Plymouth and the Baldwin were running simultaneously.