VALVES
The greatest initial concern should be valve adjustment which assures adequate valve heat dissipation and engine breathing. The intake and exhaust valve gap should be adjusted to .010 for INTAKE and .018 for EXHAUST.  With the engine cold, remove the valve covers which are underneath the exhaust manifold and behind the carburetor. The blocks use 1/2" nuts.  Use a long thin section open end wrench which is specially made for adjusting valves. This valve wrench will fit the lifter while conventional open end wrenches (7/16" & 1/2") will fit the jamb nut and tappet. The lifter (two flats) is on the bottom of the assembly, next is the jamb nut (hexagonal nut) and the tappet is the (hexagonal bolt) on top.  Between the tappet bolt face and the valve stem is the gap to be adjusted. The first valve at either end of the engine is an exhaust.  The next two are intakes, the next two are exhausts, etc., etc.  Have a friend turn over the engine by hand (a socket wrench on a flange coupling or flywheel bolt works fine) while you watch the intake and exhaust valves for a selected cylinder go up and down. Turn the engine an additional 90 degrees once both valves are down and seated.
Use a feeler gauge to measure the exhaust and intake gaps. They will probably be tight.  Put the thin section valve wrench on the lifter (bottom, two flats) and use another wrench to loosen the jamb nut (hexagonal nut). You can now turn the tappet (hexagonal bolt) to adjust the gap. If you tighten the jamb nut just enough to let the tappet turn, you can snug up the jamb nut without moving the tappet out of adjustment. Repeat this procedure for the remaining valves, doing a cylinder at a time.

IGNITION
The standard Kettering ignition system consists of a coil, condenser (capacitor), distributor, ignition switch, spark plugs, high voltage ignition wires, low voltage primary wires and a battery. The battery should be fully charged. Check the spark plug wires for cracks, frays and tight connections at the distributor cap, spark plugs and coil.

Specs.....
6 Volt Coil 1.6 ohms
12 Volt Coil 3.2 ohms
Spark Plug Gap = .025
Points Gap = .020 +- .002
Points Dwell = 38 degrees
Firing order = 153624

Spark plugs are 7/8 inch - 18 thread.
Use Champion UJ6, J6C, J8J, J8C , W-14, W-16  plugs.  The newer designations for the UJ6 & J8J are J6C (normal running) & J8C (hotter plug for low speed operation).
All spark plugs are gapped to 0.025 inches and the points are adjusted to 0.020 inches after being filed clean. To adjust the point gap, first remove the distributor cap and rotor. Crank the engine with the starter in short bursts until the points are wide open (point rubbing block on peak of cam). Adjust the point gap by loosening the jamb nut and turning stationary point until a 0.020" feeler gauge just passes through the point gap.  If using a dwell meter, adjust for 38 degrees of dwell.
Reassemble the distributor rotor and cap. To check for spark, remove the coil wire from the center of the distributor cap and position this loose wire about 1/32 inch from a head bolt. Crank the engine starter with the ignition ON and look for a white spark at this 1/32 inch gap. If there is no spark, make sure the points are clean and try again. If again there is no spark, change the condenser (capacitor) and try again.

WARNING: TO AVOID HIGH VOLTAGE SHOCKS, DON'T HOLD ONTO THE COIL WIRE WHEN CRANKING THE ENGINE. Some additional preventive maintenance includes filing the rotor tip clean, cleaning the inside of the distributor cap of any carbon tracks left by the rotor, checking the spark advance weights (below the distributor point plate) for free movement, lubricating the advance weights with a dry spray (e.g.) LPS, WD40, CRC, etc.) and lubricating the distributor shaft felt wick (under the rotor) with light machine oil. Ignition coils usually fail slowly and will usually give a red spark at the above cited 1/32 inch head bolt/coil wire gap, instead of a good white spark. Both oil filled and epoxy coils can be used with good results. Please refer to the following chart when selecting an ignition coil. For example, a six volt coil will eventually overheat and reduce its output when used with an eight volt battery.

IGNITION COIL:  By now the searchlight generator you own may have passed through several hands and you may have an ignition coil that has been replaced. Is it wired correctly?  Do you still have a positive ground 6 volt system?  If the ignition coil was replaced, chances are it is a coil that was made for a positive ground system and the wires connected wrong.  See this web page to see if your coil is connected properly... .http://mgaguru.com/mgtech/ignition/ig104.htm

STARTING UP
Assuming the above steps regarding spark plugs, rotor, cap, coil and points have been done, we can now adjust the engine.  A tachometer/dwell meter is very useful for the tune-up procedure. The six (6) cylinder engine should be set for 38 degrees of dwell angle. If necessary, readjust the points to achieve this dwell angle. Accelerate the engine up and down quickly. If the dwell angle varies more than four (4) degrees, change the points. This test indicates a weak point spring.

Timing method 1
Loosen the clamp on the bottom of the distributor and run engine at full throttle. Twist the distributor clockwise and counter clockwise until you achieve the maximum RPM. Back off the maximum by 50 RPM by twisting in the clockwise direction and tighten the distributor clamp. The engine is now timed.
If the engine loses power during the season, check the dwell angle before changing the timing.  Adjust the throttle stop screw to about 600 RPM . Turn in the low speed jet  until the RPM drops. Back out the low speed jet to 1/4 turn beyond maximum idle RPM. Readjust the throttle stop screw to the recommended idle 300 RPM. Your Engine Is Now Properly Tuned. !!!!

Timing method 2 using timing light
1 Push in the throttle button as far as it will go and adjust the stop screw on the carburetor to maintain an idling speed of
   350 rpm +- 25 rpm.
IF NECESSARY ROTATE THE IDLING ADJUSTMENT SCREW SLIGHTLY SO THAT THE ENGINE WILL IDLE SMOOTHLY.

2 ADJUST IGNITION TIMING.
     a stop the engine turn off ign.
     b attach timing light to #1 spark plug(or plug wire)
     c start engine and run at idling speed while directing the light at the timing hole in the bell housing.
     (on the exhaust side, there will be a pointer)
     d loosen the distributor clamp and rotate the dist. body slightly until lamp lights each time the white dot is seen through the
       timing hole. The white dot appears between two bolts on the flywheel. (You may have to paint this dot white.)
       Tighten the clamp. ( I would check first before loosening clamp)
     e stop engine.
     f. remove timing light etc.
 
 

Distributor Type -Autolite IGC-4227C
Points AL - 5661X
Breaker plate IGS 3004B (same as for Plymouth Dodge IGS Distributors 1940 &1949-50, Dodge Fargo 1940-41)
Rotor AL-17
Cap - AL-18
Condenser AL - 63  ( Carquest number DR60X)  .20 to .25mfd

Borg Warner Numbers....
Rotor--D208
Cap- C245

Set points at .020
Dwell = 38 degrees
Advance is 6 degrees at 900 RPM

Note:
Check your dwell setting from time to time. As the points wear, the dwell will increase.
If dwell goes higher, the engine will start to run hotter. You may see your exhaust manifold glowing red hot!  At this point the engine will not be smooth running, and may sound like it is missing. This is due to heat in the carburetor boiling the fuel. A vapor lock condition.  Always adjust the points before timing the engine as the points/dwell effects timing.  Always check timing after you adjust the points

GE Oil Filter & Gasket.
The number is NAPA 5080 Carquest 9080
Oil Filter : Carquest 85802       Wix 51802
Another filter but maybe not available, Baldwin T-307-M
A Wix 51600 will fit if you can find one.
(These filters listed above are the more modern twist on type filters that have been used by Larry Boggs)

Extend the Life of the Generator Engine by...
Get a strong magnet (old car speaker magnets work fine).
Then stick one or two on the oil filter. All metallic garbage will be stuck in the filter as it passes. When you chuck the filter, re-use the magnets on the next filter.
If you have an in-line fuel filter (even plastic ones) do the same thing.  Another way is to lower a magnet into the fuel tank with a metal cable. Then once a month or so, pull up the mag and knock off all the crud.  The least messy way is the cheap plastic filters and put a magnet on it, then chuck the filter.

The Mr. Gasket Micro Solid State Electric Fuel Pump is designed to replace the original equipment fuel pump on carbureted cars, trucks, industrial and farm equipment, lawn and garden and marine pleasure craft. Works great for fuel transfer systems in gasoline and diesel applications as well as an excellent booster pump for the existing mechanical pump.  The Mr. Gasket Micro Fuel Pump provides extreme reliability, fast engine starting in hot and cold weather without vapor locking problems. When installed properly the Mr. Gasket Micro Fuel Pumps will provide a constant fuel supply under all conditions for many years . The Mr. Gasket Micro Pump is self priming to 12" of lift, simple two bolt and two wire installation, built-in pressure relief, and has extremely low amp draw. (average 2 amps at maximum delivery).

Mr. Gasket 42S is a universal design for most import 4 and 6 cylinder carburetor applications. 12 Volt negative ground systems only.

Allied Electronics Corporate Headquarters
7410 Pebble Drive
Fort Worth, Texas 76118
Phone: 817- 595-3500
800-433-5700
Order on line here and follow instructions....
Ohmite   RRS25R

Galco Industrial Electronics
26010 Pinehurst Drive
Madison Heights, MI  48071
800-337-0552
http://www.galco.com/
Part Number RRS25R-OHM
 

Newark InOne
197 Highway 18 South Suite 205
East Brunswick, NJ 08816
800-463-9275
http://www.newark.com/
Part # 01F7651 or 64K5954

Clean the negative brush every time your replace the negative rod.  Since it does not rotate like the positive, it gets dirty faster.  The brush will last much longer if kept clean.  Next time you are in Wal-Mart pick up a .45 Cal Pistol cleaning rod, and brass brush. This is the perfect length to use to clean the Neg brushes, and the .45 cal brass brush works great. A few passes back and forth, then hit with graphite spray and scrub it again.  You can also use a Flex Hone. Attach it ot the end of a drill, and clean the brush right out.

Negative Brush on a GE light If you see the upper part of the brush getting too thin on a GE light, replace the brush.  If you don't, the metal gets so thin that the material will not be able to carry the current. As a result, the brush will glow RED HOT, and soon will start to melt. There is no warning, and it happens very fast. It will just happen while you are running the light and start to melt.

Clean your brushes: Use a Flex-hone to clean your positive and negative brushes.  Just attach to a drill, spray on a little graphite on it, and pass through a few times.  Keep your brush surface smooth for the carbon to pass through with ease.

Brake Cylinder Flex-Hone - 11mm x 8 In - 180 Grit
Brake Cylinder Flex-Hone - 5/8 x 8 In - 180 Grit

You can get them at some tool stores or on the internet at ZORO TOOLS...
Zoro.com
11mm

Zoro.com
16mm -  5/8"

Positive Rotation Gear:
Always be sure your positive rotation gear is greased.  Hard to say what is best.
Here are what some operators have been using.
Copper Anti Seize Lubricant from Loctite good up to 1800 degrees.
http://www.shopatmidway.com/p-3911-copper-anti-seize-lubricant-8-oz-brushtop-bottle.aspx
John Deere Grease, same feel as wheel bearing grease
DUPONT lube with Teflon spray on.  The oils burn off with the high temps, but the teflon doesn't.

On Rainy Nights: put your carbons inside the light drum. Some lights have carbon holders inside the drum for this. You can also mount a can along side the tower, and put your carbons in the can. When the light is on, it it will get hot enough to cook out any moisture in the rods.  Drum interior runs at about 120 F.

Historical Note: You may think it is a design flaw because there is no means of auto shut off to prevent the heat shield from burning up when the positive rod runs out.  This is not true.  They never had these meltdowns during the war because a positive rod ran out .  One reason is they would always start with a fresh set of rods if the last set had more than a 1/2 hour run time on them.  Another reason is they used sets of military issued rods. These military negatives were shorter than some of the commercial 17 inch rods we use today, and the negative would always run out before the positive rod.  The light would just go out when the negative ran out, a signal to the operator who would turn the power off and  re-carbon the light.

Sperry Control Box Test and Alignment
The easy way to test and align a Sperry control box is to remove your carbon rods.
Adjust your  generator to provide 78 volts to the searchlight.
The goal is to adjust the negative auto feed so it does not move the rod in or out at all with 78 volts applied.
The control box motor will run, and the negative feed ratchet should come to rest in a neutral position and not feed at all.
Adjust your negative feed screw on the far right so the Negative Feed Knob on the far left does not move at all.
If voltage goes up or down from 78 volts, it will move the armature in or out to feed or retract the negative rod. With the gap properly set, and voltage set at 78 volts, the tension spring should be adjusted to where the ratchet fork comes to rest between the feed and retract gears.  Be sure this fork does not rub on either gear wheel.  You can adjust the gap between the armature and coil frame by loosening the two screws on the top of the frame. It pinches a spring metal hinge so you can move this metal plate in or out.  To adjust he spacing of the armature and coil, loosen the nut that holds the coil in place and either add or remove shims that might be there.

THERMOSTAT LENS ADJUSTMENTS

a. GENERAL

(1) When the lamp is replaced in the drum, the thermostat lens adjustments should be checked. The correct adjustments and the method of adjustment is described below:

(2) The thermostat lens should be adjusted so that the image of the positive carbon, when set at 11/16 of an inch protusion, will appear on the thermostat cover as on the instruction plate within the drum.

(3) The image of the positive carbon may be projected on the thermostat cover by placing a bright flashlight behind the carbon tip, or the arc may be struck which will project the luminous image of the positive carbon on the thermostat cover. The former method is prescribed for preliminary adjustments and the latter for final adjustments. The shadow image can be made distinct by securing a small sheet of white paper to the thermostat cover and outlining the windows by heavy pencil lines on the paper. The shadow image can be improved further by positioning the searchlight in a dark corner of a building or by excluding daylight or other interfering light from the interior of the drum by means of a cover. Both the cover and sheet of paper must be removed before striking the arc.

(4) The image may be positioned on the thermostat cover, as required for effective arc operation, by the adjustment given below.

b. FOCUSING

The shadow image can be made clear and sharp by moving the lens holder bracket (8, fig. 7) along the compensating link within the limits of the slot. Loosen the two mounting screws and slide the bracket either toward or away from the lamp until the shadow image is sharp and clear. Secure the bracket in that position.

c. VERTICAL POSITIONING

The shadow image may be positioned vertically, according to the instruction plate within the drum, by raising or lowering the lens holder (9, fig. 7). This either raises ot lowers the image on the cover and can be accomplished by loosening the jam nut (see 8, fig. 7) on the lens holder screw and screwing the lens holder up or down. Before tightening the jam nut, make sure that the lens is positioned at right angles to a line drawn from the tip of the positive carbon to the tip of the image on the thermostat cover, passing through the center of the lens.

d. HORIZONTAL POSITIONING

The image of the positive carbon may be positioned horizontially according to the instruction plate within the drum by moving the compensating link (7, fig. 7) toward or away from the mirror as required, or by moving the lens mounting bracket in the same direction by sliding it across the compensating link. The second method is limited as the slot is narrow.

(1) If the lamp is not equipped with beam spread, the compensating link may be moved by loosening the clamp screw (13, fig. 12) and rotating the lens link driving pin (20).

(2) If the lamp is equipped with beam spread, loosen the two drive stud plate cap screws (14, fig. 7) and position the plate as required by the image. Tighten the cap screws. Check to see that the tip of the shadow remains in approximately the same position on the thermostat cover, regardless of lamp position. With the lamp at focus position and the positive carbon protrusion still at 11/16 of an inch, mark the position of the tip of the carbon on the thermostat cover. Slowly move the lamp, and the light behind it, from focal to beam spread position and watch the tip of the shadow image in relation to the line scribed above. If the image shifts, loosen the drive stud (13, fig. 7) by merely turning the head, and shift the position of the stud until the image remains approximately stationary as the lamp is moved from one extreme to the other.
 

You should also check the semi-autofeed. It is important that is working too. Just make sure it isn't feeding the carbon too much! It is better to have it feed slightly less and let the thermostat catch it and kick up the carbon than over feeding since there isn't a way to retract the positive carbon. Here is the procedure to align the semi-automatic feed on the Sperry light:

Procedure from the Sperry manual below:

47. LAMP OPERATING MECHANISM, ADJUSTMENT

a. The recommended rate of semi-automatic feed is at about one-half the rate of carbon consumption. Semi-automatic feed is adjusted roughly to this rate as follows:

(1) Remove both positive and negative carbons from the lamp.

(2) Loosen the semi-automatic positive feed screw locknut (see 2, fig. 31). Throw the arc switch ON. Turn the semi-automatic positive feed screw until the positive feed plunger operates.

(3) While the feed mechanism is operating, turn the screw clockwise until the plunger operates for only an instant throughout one complete revolution of the positive feed roller bracket (5, fig. 15).

(4) When the above adjustment is reached, turn the arc switch OFF.

(5) Then turn the semi-automatic positive feed screw 1-1/4 turns counter-clockwise. Tighten the locknut.

(6) Operate the arc and check to see that the periodic semi-automatic operation of the plunger occurs not more than one sixth of the time.
 
 
 

Glass Cleaner: To remove the chemical etching off the glass you can use  the Janvil Glass Restore system.
One operator reported that he had streaking on the inside his glass....   almost like water channels.  It could have been from when the mirror was acid washed  years ago, and that there was splash over onto the glass.  It would not come off with any household chemicals. I bought the product and used it as directed.  The stuff worked wonderfully. Using only the "glass renew"  90% of the staining/etching was removed. The tough spots and I used the scratch remover and then the glass renew and that took off the tough stuff.  It looks 100% better.
It is definitely easier doing it with the glass out and seems to do a better job.  Took me about an hour to do the whole lamp. Used about 1/3 of the bottle of the "Glass Renew".  I highly recommend it.
Get it here.....
http://www.janvil.com/glass_restoration.htm

Searchlight Mirror Polish.  This is something new. $9.99 for a 2 oz bottle.
This polish removes ALL of it in one cleaning and is a lot easier that you would expect!
Simply wipe on and polish off. NO WATER OR GLASS CLEANER NEEDED !!!
This polish is a NON-ABRASIVE CREAM, one container is enough to clean a 60 inch mirror 1 - 6 times depending on how bad and dirty the mirror(s) is/are. CONTACT:
Ron Peters WhiteGaugeGuy@aol.com
10625 Kingwood Drive
Corpus Christi, TX 78410
(361) 244-0679

Searchlight Mirror Replating Information
From Robert Doerr
The Nickel may have been used as a base for the plating process but I don't think it would make a good final finish for the mirror. From everything I've read Nickel and Chrome finishes aren't nearly as reflective as Rhodium or Silver. A couple links that talk about it:
http://www.finishing.com/271/71.shtml
http://www.finishing.com/1400-1599/1533.shtml
Some details on Rhodium:
http://en.wikipedia.org/wiki/Rhodium
Here is a new place I just found that does plating. Perhaps someone is near them and can see if they can handle plating an object as large as a 60" searchlight mirror.
http://niprooptics.thomasnet-navigator.com/item/all-categories/reflector-refurbishing/item-1004?&forward=1
I had talked to some plating companies years ago and they said that Rhodium was probably the best material to use for the final finish. The issue with plating the mirror is the sheer size of it. They are huge and the time to setup a special fixture for plating them is a big investment in time/material. Most shops aren't use to plating parts that big.
Hopefully someday someone will find a plating company that can handle the job so people can get their mirrors redone when needed.
 
 
 

Place a piece of paper between the positive intermittent feed contacts located under the guard in the lower right had corner of the control box to disable the semi auto feed.

Operate the arc for at least ten minutes. While the arc is on,  if your thermostat mirror is in spec or close, it will be noted that the positive feed magnet will pickup up an drop out at regular intervals. During this time, keep an eye on your sight glass to be sure the carbon does not burn back to the danger line. If your thermostat does not cycle the magnet, it could be way out of alignment, the points in the thermostat could be burnt, and the metal strips will need to be replaced, or the wire from the thermostat to the control box has a bad connection.
The positive carbon feed occurs only when the armature of the positive feed magnet is picked up. The feed starts when the armature picks up and stops when the armature drops out.

After ten minutes of arc operation, turn the arc off immediately following the start of a positive feed cycle.
Measure the projection of the positive carbon beyond the positive nose cap. If the projection is less than 3/4 of an inch, loosen the locking bolt to adjust the mirror as follows...

Turn the mirror adjusting eccentric to move the fork of the mirror mounting bracket toward the lamp.  Move the fork only a small amount at a time. Tighten the locking bolt before rechecking the positive carbon protrusion.

Operate the arc for four to five feeding cycles, and then check the projection for the positive carbon again. Repeat the above operations until the positive carbon projection is held at 3/4 of an inch, on the focal line of the sight glass.

In general, if the positive rod is not being maintained on the focal point line of the sight glass, and is behind, then move the mirror a bit toward the arc. If the positive rod is maintained beyond the focal point mark, then move the mirror away from the arc.
Don't forget to remove the paper from the points when you are done testing.
The Semi auto knob should be adjusted to where the points energize the feed magnet just behind the thermostat so the feed does not exceed the focal point line on the sight glass.  If the thermostat should fail, the semi auto points will take over to feed the positive carbon.

Note: if the mirror is moved too far, the thermostat will power the magnet to feed all the time.
If you load up a positive carbon with too much protrusion, the thermostat may also keep the magnet energized and over feed.
If you loose a blower motor, and it gets really hot inside, the thermostat will keep the magnet energized and over feed.

The ballast is used to limit current so you can have the carbons closer together to arc.  It also puts less stress on the generator by limiting the current when striking the arc.  The ballast resistor is also the reason for the drop in voltage between the generator and the light.  It is not a good idea to run the light without a ballast.
Below is a schematic of how the ballast resistor is wired in a GE Searchlight.

There are 3 lugs. One for 600 ft, 400 ft, and 200 ft. cables.  There is only one way to correctly connect the ballast resistor to a light using short cable less than 200 ft in length, and that is using the 600 ft lug and the 200 ft lug. The 600 ft lug is really a common tie point where the cable from the generator will always stay. The cable from the light can be moved to all three lugs.
Here are the ways you can connect to the ballast and the results you will get.....

1) The cable  that comes in from the generator is always on the 600 ft lug on the far left and wire that goes to the light should be on the 200 ft lug on the far right.  You will get .088 ohms of resistance.

2) If you attach the wire going to the light to the middle 400 ft lug, you will get .044 ohms of resistance.

3) If you attach the wire going to the light on the 600 ft lug, you get 0 ohms. The ballast is out of the circuit. The resistance of the length of wire becomes the ballast resistor with a total value of .132 ohms of wire resistance.

4) If you put one wire on the 400 ft lug and the other on the  200 ft lug you will get .044 ohms same as #2 above as when 400 ft and 600 ft is used.

In each case above, the length of cable used adds resistance along with the ballast.  With the short cables we use to run our lights, we want to connect to the 200 ft lug for .088  ohms. Any less will put more stress on the generator.  As it is, we are running with a shorter cables, and therefore less resistance than the light would like to see.  With a 200 ft cable the total resistance would be another .088 ohms added to the ballast resistance for a total of  1.76 ohms.  So actually, with our short cables, we should be using a ballast resistance of 1.76 ohms.   To compensate for our short cables, we use our rheostat to adjust the voltage down from the 115 volts the manual says we should have at the generator to about 93 volts to allow for 78 volts at the light when the arc is on.   If we had 200 ft of cable the added resistance would cause a large drop in voltage, and allow us to raise the generator voltage to 115 volts.  Again, we actually need a ballast resistor with a value of 1.76 ohms to run with short cables to be in spec. and run our generator voltage up to 115 volts at the generator.

Through the KenCor Electric Equipment company, they have come up with a stamped grid resistor to replace the edge wound type that GE now uses.  The advantage being newer technology, and much higher durability.  They don't have ceramic in them, and they don't break the clips, there are no clips.  Also, they're duty rated for 200 amps.  Exactly the .088 ohms of resistance needed.  In 1942, all GE units had  edge wounds, and they're great for installed applications.  BUT, they don't work well for mobile, and "tailored" vehicles, e.g. searchlights.  So, the stamped stainless stuff should be much better, and last longer than the edge wounds.  The only disadvantage, if you can call it that, is that the box is approx. 3-4 inches taller than the OEM.  Takes 3-4 weeks from order time, but can be rushed to 24 hours if necessary. The unit would be $480 plus shipping.
KenCor Electrical Equipment
3015 East Skelly Drive Suite 103
Tulsa, OK 74105
Tel: 918-745-6066
Fax: 918-747-2747
Attn:  Barry Holcombe

Wet Carbons rods do not work properly in the searchlight.  Carbons must be dry.  If your carbon rods get wet, just bake them in the oven to dry them.  150 C  or   300F for an hour or so.  They will be good as new.

In general, the control box for both Sperry and GE lights are responsible for three things...
1) rotate the positive rod
2) feed the positive rod, and maintain the rods position at the focal point of the mirror
3) feed the negative rod so it maintains a distance from the positive rod to give you 150 amps of current.
There is one DC motor that operates at 78 volts in this box that controls all of these things.

For all of this to happen, the voltage at the light must be 78 volts at the light when the arc is on.
Once the arc is on, this voltage can be adjusted at the generator using the rheostat.
The voltage at the generator will not be the same as at the light when the arc is in operation.
The generator will be about 93 volts and the light is 78 when the arc is on.
When the arc is off, both voltages will be the same.

To maintain the positive rod position, there is a thermostat that controls the positive feed. This thermostat is mounted on the wall of the drum just below the control box on a Sperry, and on the GE it is mounted on an arm just to the right of the positive feed unit.  The light from the tip of the positive rod is directed, and focused  on the thermostat using a  a magnifying glass on the Sperry and a mirror on a GE light.
Inside the thermostat is a set of bimetal  strips with contacts. As the positive rod burns down, the position of the light on the thermostat will change causing one of the strips to get hot, and bend.  This bending causes the closing the points to actuate the positive feed coil. On a Sperry, this coil is mounted on the front of the positive feed unit on the burner. On a GE light this coil is mounted in the control box and is connected to the positive feeder on the burner by a long control rod.
When the rod is fed back into the focal point position, the bimetal strip cools a bit and the points open. The rod should be back on the focal point line, and stay there until it burns back.. The cycle repeats over again..
Both Sperry and GE lights have a backup system made up of a  leaf switch that rides on a lobe that is driven by the motor in this box.  As the the switch rides up, and down on this lobe, the points open and close.  Each time the point close on this switch, it activates the positive feed coil that allows the positive rod to feed a little bit forward.
There is an adjustment on this switch that you can set to have it close the coil for a long time or short time. It should be set so it just maintains the positive carbon just behind the focal point line on the site glass. In other words it should feed just a little slow so that the thermostat kicks in once in a while.

The negative feed, and position is dictated by a voltage coil on a Sperry and a current coil on a GE light.
The voltage coil on a Sperry is located on the back of the control box. You can't get to it. This coil senses 78 volts. The coil suspends a control arm inside the  box.  If the arc is burning at 78 volts, the arm does nothing, but if the voltage should change, the magnetic field of this coil will either be weaker or stronger causing the arm to raise or lower causing a ratchet device to engage and drive the rod in or out as needed.

On the GE light, the negative rod position is dictated by the current coil. This coil is located on the upper left hand side of the box.  All the current going through the arc goes through this coil. The coil maintains the position of a contact  between two points. When the current is right at 150 amps, the points are suspended between the points and nothing happens. If there is a change of current, the points will move up or down depending if it senses an increase or decrease in current which creates an increase or decrease in the magnetic field suspending the points, and feed either the feed or retract magnetic coil on the clutch that will move the negative rod in or out until 150 amps are set.

Sperry 1941-A Searchlight see it here!
Sperry Generator Schematic see it here!

1945 Seacoast Searchlight Manual  see it here

Light Source: 1 inch Carbon Arc (no light bulb!)
Candle Power: 800,000,000 (800 million)
Effective Beam length: 5.6 miles
Effective Beam visibility: 28~35 miles
Glass Weight Totals: 75 lbs
Brass Rhodium Coated Mirror: 165 lbs

GENERATOR:
Generator Power: 15 KWV nominal - 16.7 KWV max. (15,000~16,700 watts D.C.)
Powered By: In line 6 cyl. "Hercules" Flathead Engine
Generator Engine Fuel: Gasoline (can also be run using Kerosene or Gasohol) 26 gallons
Generator Fuel Consumption: 2.6 Gal per hour
Combined Weight: 6,000 pounds (3 tons, or the weight of 3 Ford Mustangs combined!)

Light Source:
The Beam is made by 2 carbon rods, one positive and one negative, arching within the focal point of a 60 inch
parabolic mirror. The actual light source is only 1 inch in diameter at the tip of the positive carbon.  It is then magnified by the mirror.  As the rods "burn" they are automatically fed into the arc. The rods last approximately 2 hours and then are replaced. The flame that is visible during the lights operation, is not actually the source of the light, rather, it is a by-product, produced as a result of the electricity arching between the 2 rods. The flame is the rod slowly burning away as it is fed into the light. The arc draws 150 amps continuously at 78 volts DC, and burns at over 3,000 degrees Fahrenheit. The power is supplied by the D.C. generator which was designed specifically for this purpose.

Check out the LIGHTSKY website, a very valuable “tool” for the carbon arc operators that helps fight the darksky.org folks.
Hopefully this website will allow searchlight operators to give “our side” of the story to City Zoning and Council members and to provide those people with facts, not fiction before banning searchlights for the benefit of a few.
http://www.lightskydarksky.org/

10-14-2005. A light operator had a phone conversation with the Southwest Regional office of the
FAA - Branch 530
The 530 branch of the FAA covers operations in:
Texas, Arkansas, Oklahoma, New Mexico, Louisiana
He spoke with the Regional Manger, Mr. Tervino:
Mr. Trevino illustrated several things . . .

1.  The FAA does not have any rules and regulations in regards to the use of 60" GE or Sperry Searchlights that are "on the books".
    a. There are NO formal FAA rules and regulations about the use of, ownership or operation
        of 60" Diameter 800,000,000 million candle power searchlights.
    b.  The FAA does have rules on the use and operation of Lasers and Laser Light shows.
        1. See Advisory Circular - Outdoor Laser Operations - 12/30/2004 - AC No. 70-1
        2. Form "Notice of Proposed Outdoor Laser Operation(s) - Form AC-70-1, FAA Form
            7140-1 (4-01)
        3. To be used in conjunction with "Laser Configuration Worksheet" sub part of FAA Form
            7140-1 (4-01)
    c. The only time that the FAA would intercede in the operation of a searchlight light source is:
        1.  If the use of the searchlight jeopardizes on infringes upon aircraft or flight operations
             directly.
        2.  The FAA is mainly concerned with the approach to landing or take off of aircraft and
             the orientation of the Pilot.

2.  The FAA recognizes and works with the searchlight operator as they deem them a bona fide business and the FAA operates under a "good neighbor" policy instead of having formal rules and regulations in regards to the operation of searchlights.

3.  The FAA requests that the search light operator submit the following information to the FAA prior to operating their searchlight.

    a. Fax in a "Proposed Operations Statement" - no formal form, but a form created by the
        owner/operator or company operating the search light.
    b. Include approximate location of search light operation, i.e. At the intersection of Main
        and 4th Ave., Dallas, Texas 75227
    c. Include the hours of operation, i.e. 8:00pm - 12:00 mid-night
    d. Include the date of operation, i.e. 10-15-2005
    e. Include POC or Point of Contact information for the operator on site.
    f.  Include Contact Numbers for operator or company.

4.  If the form can be faxed on or before close of business on the day of the operation the FAA
would appreciate it.
Once the Proposed Operations Statement has been received the FAA will then make all local airport and aviation facilities aware of the operation, day, date and times.  If the operation of the light is in direct conflict with the operation of any immediate aircraft or air operations in the proposed area, the FAA will contact the searchlight owner/operator and discuss the issue further.

If there is an issue with the operation of the searchlight:
1.  The FAA may request a deviation in the location of the use of the searchlight.
2.  The FAA may request that you do not operate the search light at all.
3.  The FAA may request a deviation in the times the searchlight may be operated.
4.  The FAA may want to discuss the angle or directions of operation.

In a worse case scenario the FAA may demand that the searchlight not be operated if it directly affect the operations of any aircraft or air operations.  Mr. Trevion did indicate there there are rules and regulations in regards to interference of aircraft operations and though he has never heard of the FAA enforcing any of those rules he said if an searchlight owner/operator refused to work with the FAA and it endangered aircraft or air operations he said if all other options had been exhausted the FAA would then take action.

Mr. Trevino - bottom lined it this way - "it is a common sense issue" we (the FAA) are willing and enthusiastic about working with any searchlight owner/operator but both parties have to subscribe to a common sense attitude and develop a working relationship based upon mutual respect.

POC Information for FAA Regional Office 530

Manager - Mr. Trevino
(817) 222-5595 - direct line
(817) 222-5547 - fax
 
 

UPDATE from Operator Brett Peabody 7/14/2008
Several people in the advertising searchlight industry reassured me that operating a searchlight is “not against the law”.  But, I was not completely satisfied with those comforting words.  So I set out to hear from the most authoritative source I could find how federal regulations affect searchlight usage.  I studied Your article on “FAA Regulations of Searchlights” and had a short talk with Mr. Trevino, who you mentioned in your article.  He told me that the key contact for searchlight usage is Mr. Steve Rohring in Washington DC .  Mr. Rohring’s direct number is (202)267-9231.

I spoke with Mr. Rohring today, and he was very helpful.  He patiently answered all of my questions and he helped me to understand exactly how FAA regulations apply to searchlights (as you may know, the FAA calls them “high intensity lights” or “HIL’s”).  There are apparently no changes to report since your 2005 conversation with Mr. Trevino in FT. Worth .  The FAA is still apparently much more concerned about lasers than they are about HIL’s.  Nevertheless, Mr. Rohring says that HIL’s are still a serious concern because HIL’s have been mentioned as a factor in several aviation accident reports.  Mr. Rohring is currently heading an effort to develop guidelines and advisories specifically written for HIL operators so we will not have to continue to rely on forms and information that are actually intended for laser operators.  He said that the project will take a while to complete, maybe up to a year.  Until then, he advised that we should continue to report our planned operations for evaluation in the manner described in your article.  When Mr. Rohring’s project is completed, the FAA should be able to provide new operators like me with better guidance on how to comply with FAA guidelines.  Mr. Rohring did not indicate that there will be any immediate changes in the regulations themselves.

Here’s my understanding of the FAA regulations and guidelines pertaining to HIL’s:  HIL use is generally not restricted by federal statute or regulatory law unless the HIL somehow interferes with the safety of the navigable air space (NAS).  The most sensitive areas are near airports or near heavy air routes where HIL’s may interfere with pilots’ vision during takeoff, approach, or landing.  If there are any reportable “incidents” involving HIL’s, then the FAA and other agencies are authorized to take various enforcement actions.  Enforcement actions can be a very bad thing for operators, so we want to avoid reportable “incidents” at all costs.  The notice and “objection” processes described in your article are intended to avoid “incidents” and to help keep the NAS safe for air traffic.  When we provide prior notice of our HIL operations to Mr. Trevino or to one of the other two coordinators in other regions, FAA does not approve or disapprove our operations; rather, they merely take the opportunity to “object” or “not object” to how we use our lights.  Since filing notice is voluntary, we can choose to ignore FAA’s objections, but that would be a really big mistake!  I suspect that the penalties are very harsh for operators who cause reportable incidents after disregarding FAA objections.  I also suspect that civil liabilities increase dramatically for operators who ignore FAA objections or who never provide any notice at all.

Based on what I learned, I plan on always providing advance notice to the FAA for all my HIL night usage according to the instructions in your 2005 article.  I feel that the FAA is very supportive of the searchlight advertising industry, but that support could easily dissolve if the industry fails to comply with FAA’s safety guidelines.  If the FAA sees that operators voluntarily follow their recommendations and guidelines, then they may not feel the need to impose new rules to force us into compliance.  The whole purpose of these notice guidelines is to help avoid accidents caused by exposure to our lights, so we should not resist the FAA’s efforts to get proper notice.  FAA does not apparently want to shut down our operations; they simply want to study our operations in advance and to suggest ways to make the operations safer.  FAA might suggest that we adjust the elevation of the light, change our direction, reposition our light, or screen the light in certain directions by using natural or man-made barriers to block exposures.  Even within critical range of an airport (10 miles or less) there may still be ways to safely operate our lights.

Mr. Rohring encouraged me to get in contact with Mr. Trevino at the Ft. Worth FAA office and to establish a long-term relationship with him by regularly sending him notices of my planned HIL operations.  There are two other regional coordinators that cover other parts of the nation for the FAA.  I didn’t get their names, but I think the names are available on the FAA website.  Mr. Rohring said that they prefer 30 days prior notice of HIL operations to allow time to do a thorough study of the surrounding airspace.  But, shorter notice is sometimes acceptable.  Once a particular location is studied, then it may not be necessary to send notice every time we operate at the same area, but that will be at the discretion of the FAA regional coordinator.

If all other operators also do their best to comply with FAA’s voluntary guidelines, then maybe the FAA will let us continue to operate with the freedom that we now enjoy for a long long time.  All it would take is a few unsafe “incidents” and the government could restrict the searchlight advertising industry right out of business.  So let’s be safe out there!