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MALLORY POINTS TYPE DISTRIBUTORS - IG-202 - Page 1 of 3
This is the instruction set which comes with a Mallory points type distributor.

INSTALLATION PROCEDURE - MALLORY DISTRIBUTORS
Standard and Vacuum Advance -- Single and Dual Point

  1. Locate No. 1 cylinder on distributor cap (see figure 1). Mark distributor housing in line with that position.
  2. Remove the distributor cap. Do not remove the plug wires or coil wires at this time.
  3. NOTE: Removal of spark plugs at this time makes the engine cranking much easier. Crank engine slowly until the rotor is pointing at mark on distributor housing and timing marks are aligned. After locating No. 1 cylinder DO NOT crank engine until after new distributor is installed.
  4. Remove distributor primary wire connected from distributor to negative terminal of coil [negative earth system]. If original distributor is a vacuum advance unit, note the direction that the vacuum champer is pointing and remove the vacuum line. Remove the original distributor.
  5. Remove cap from Mallory distributor. If a vacuum advance unit is being replaced, turn the Mallory distributor so that the vacuun chamber is pointed in the same direction as the originsl. If the original had no vacuum advance, and is being replaced by a Mallory vacuum advance unit, point the vacuum chamber so that there is room to turn the distributor for timing adjustment. In all cases, line up the rotor so that it points in the same direction as the original, and install it in the engine block.
  6. Rotate distributor body in opposite direction of rotor rotationuntil points just open. Tighten holding clamp so distributor body will not move. Place a mark on distributor body in line with the rotor blace center.
  1. Reinstsall distributor cap. The sparkplug wire tower of the cap which lines up with the mark on the distributor body is now designated No. 1 cylinder. Remove No. 1 cylinder plug wire from original cap and place in No. 1 tower on the Mallory distributor cap. Remove wires, one at a time, from the original cap and install in Mallory cap in the same rotation and sequence as they were removed from the original cap. Remove coil wire from original cap. Install this wire in the Mallory cap.
  2. Connect primary wire from negative terminal of coil [negative earth system] to the distributor terminal.
  3. If installing a non-vacuum distributor, skip to step 10. For vacuum advance units, locate the original vacuum line. If none is present, a line must be run to the ported vacuum source. Do not connect this line until after the engien has been timed. Temporarily plug this line.
  4. CAUTION! - FOR THE FOLLOWING PROCEDURES MAKE SURE THAT YOU AND ALL OF THE WIRES FOR THE TIMING LIGHT ARE CLEAR OF THE MOVING ENGINE PARTS, SUCH AS THE FAN AND ANY BELTS, POWER STEERING PUMPS, ETC.
    Connect a timing light. Install the distributor calmp and tighten it just enough so the distributor can be rotated for timing purposes. Start the engine and rotate the distributor so that the timing is as recommended by the manufacturer.
    Tighten the distributor clamp and make sure that timing is still correct. If not, repeat step 10.
  5. If a vacuum advance distributor is installed, remove the temporary plug from the vacuum line and connect it to the vacuum chamber.

--------------- GENERAL SERVICE INFORMATION ---------------

LUBRICATION: Every 50 hours apply a light film of grease on the cam lobes. Apply chassis lubricant with a hand gun to tach drive grease fitting. (Stop at the slightest back pressure.)
CENTRIFUGAL ADVANCE: Springs are adjusted by using a screw driver in the circuit breaker plate holes. DO NOT DAMAGE the spring loops. If necessary, disassemble, place a light film of grease at the upper shaft and a light film of oil on all other parts.
TACHOMETER DRIVE ASSEMBLY: Use a suitable wrench and disassemble tach drive assembly. Clean all parts and inspect for wear. Reassemble, lubricating all parts with hand gun.
COIL CHECK: Remove the coil output wire from the distributor cap. Hold this wire about 1/2" away from ground. Crank engine with the ignition key "on". A reasonable snappy blue spark should be obtained. If spark output is weak, check secondary wiring, and all wiring and connections in the primary circuit. If these parts are okay, remove coil for testing.
DISTRIBUTOR CAP: To test for a secondary breakdown, position the cap so that the inner segments can be seen.

 

Turn ignition key on and crank the engine. The high voltage entering the cap from the coil will arc across any portion that may be defective. If the cap is free from defects, check the seating of each spark plug wire and clean all surfaces.
ROTOR: To test, remove the distributor cap. Remove the coil wire that leads into the cap. Hold this coil wire 1/2" above the rotor. Crank the engine with the key on; no sparks should be obtained. If the rotor is defective, a high voltage spark will pinpoint the exact location of the defect. Replace if necessary.
POINT ADJUSTMENT: Adjust the breaker points as shown in the table below for the appropriate model distributor you have installed.
CAUTION: IN MODELS WITH THE TRIANGULR HOLE IN THE BREAKER PLATE, EXERCISE CARE IN USING A SCREWDRIVER TO ADJUST THE SETTING, AS IT IS POSSIBLE TO EXTEND THE SCREWDRIVER BLADE FAR ENOUGH TO DAMAGE THE ADVANCE MECHANISM IF THE DISTRIBUTOR SHAFT IS ROTATED.


 
-------------- CIRCUIT BREAKER ADJUSTMENT --------------
SINGLE POINT DIST: DUAL POINT DIST:
TYPE OPENING (EA) DWELL (EA)   TYPE OPENING (EA) DWELL (EA) DWELL (TOTAL)
8 cyl.018"29-31 8 cyl.022"2631-35
6 cyl.022"31-33 6 cyl.028"2934-37
4 cyl.018"34-36 4 cyl.022"3239-41
-------------- TUNE UP PARTS -------------- 8 cyl stack cap - 1 - 25042 points, 1 - 309 rotor, 1 - 400 condenser, and 1 - 209 cap. 8 cyl flat cap - 1 - 25042 points, 1 - 319 rotor, 1 - 400 condenser, and 1 - 221 cap. 4 CYL & 6 CYL DISTRIBUTORS WITH PREFIX 25 & 26 ARE: 6 cyl - 1 - 25042 points, 1 - 320 rotor, 1 - 400 condenser, and 1 - 226 cap. 4 cyl - 1 - 25042 points, 1 - 320 rotor, 1 - 400 condenser, and 1 - 226 cap. 4 CYL & 6 CYL DISTRIBUTORS WITH PREFIX 23, 24 & 27 ARE: 6 cyl - 1 - 25042 points, 1 - 309 rotor, 1 - 400 condenser, and 1 - 270 cap. 4 cyl - 1 - 25042 points, 1 - 309 rotor, 1 - 400 condenser, and 1 - 271 cap. Vacuum advance to use No. 157 points. NOTE: Dual Point Distributors require two sets of 25042 points.

REPLACEMENT PARTS: When ordering replacement parts, other than tune up parts, specify Model and Type of Distributor. This is necessary to insure that we deliver the correct replacement parts. The Model and Type of the Distributor is shown on the nameplate attached to the side of the housing.

ADVANCE CURVE SPECIfICATIONS ARE AS FOLLOWS 2548201 28 @ 3000 engine RPM 2557901 20 @ 3000 engine RPM 2554101 28 @ 3000 engine RPM 2558301 20 @ 3800 engine RPM All other dual point distributors that end in 01 have 24 @ 3000 engine RPM.
Continue on to Firing Order and Degree Key Instructions.
 
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