Mallory Ignition Mallory Distributors 23_25_27 - Manual (Page 4)

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 adjustable 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.
INSTALLATION PROCEDURE
Step 1
Locate the spark plug wire on the original distributor cap that the engine timing is set
from. (See service manual for these locations.)
Step 2
Remove the distributor cap. Do not remove the plug wires or coil wire at this
time.
Step 3
Turn the engine crankshaft in the direction of rotation until the timing mark lines up with
the top dead center (TDC) mark on the timing tab (See a service manual for these
locations). NOTE: Once this step is finished, DO NOT turn the crankshaft until the
new distributor is installed.
Step 4
Remove distributor primary wire connected from distributor to negative terminal of coil. If
original distributor is a vacuum advance unit, note the direction that the vacuum chamber
is pointing and remove the vacuum line. Remove the original distributor.
Step 5
Remove cap from Mallory distributor. If a vacuum advance unit is being replaced, turn
the Mallory distributor so that the vacuum chamber is pointed in the same direction as
the original. If the original had 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. Be sure that the
distributor is seated in the block.
Step 6
Rotate distributor body in opposite direction of rotor rotation until points just open.
Tighten holding clamp so distributor body will not move. Place a mark on distributor body
in line with the rotor blade center.
Step 7
Reinstall distributor cap. The spark plug 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
spark plug wire from original cap and place in No. 1 tower on the Mallory distributor cap.
Remove spark plug 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.
Step 8
Connect primary wire from negative terminal of coil to the distributor terminal.
Step 9
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 a ported vacuum
source. Do not connect this until after the engine has been timed. Temporarily plug this
line.
Step 10
CAUTION: For the following procedures make sure that you and all of the wires
for the timing light are clear of moving engine parts, such as the fan and any
belts, power steering pumps, etc.
Connect a timing light. Install the distributor clamp 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.
Step 11
If a vacuum advance distributor is installed, remove the temporary plug from the vacuum
line and connect it to the vacuum chamber.
(LEGAL IN CALIFORNIA ONLY FOR RACING VEHICLES WHICH MAY NEVER BE OPERATED UPON A HIGHWAY)
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