MALLORY 556

FORM 1411 (REV. D) 8/08
INSTALLATION INSTRUCTIONS
UNILITE® DISTRIBUTOR FOR
1936-69 HARLEY DAVIDSON®
BIG TWIN MOTORCYCLES
Part No. 556
NOTE: THIS DISTRIBUTOR WILL NOT FIT FLAT HEAD OR SPORTSTER® ENGINES.
IMPORTANT
A 1966-69 HARLEY DAVIDSON DISTRIBUTOR CLAMP (ORIGINAL OR AFTERMARKET)
IS REQUIRED TO INSTALL THIS DISTRIBUTOR. BECAUSE THE UNILITE® MODULE USED
WITH THIS DISTRIBUTOR REQUIRES 7-16 VOLTS, A 12 VOLT ELECTRICAL SYSTEM IS
ALSO REQUIRED.
®
GENERAL INFORMATION
INSTALLATION
Any coil or combination of coils with a total primary resistance of at
least 2.0 ohms can be used with this distributor. We recommend a
2-3 ohm coil for racing and a 3-4 ohm coil for street use. A coil with
4-5 ohms resistance may be used. However, performance may be
reduced, even in street applications. NOTE: Check the charging
system and make sure that it is producing no more than 16 volts.
Step 1
Turn the ignition switch to the off position. With the point distributor still
in place and correctly timed, rotate the engine until the points begin to
open on the front cylinder lobe. The front cylinder lobe is the narrower
of the two.
We recommend a spark plug gap of .040” when using a 2-3 ohm
coil. A gap of .030” is recommended when using a 3-4 ohm coil.
If the point distributor is not installed, rotate the engine to the beginning of the compression stroke. Locate the timing hole. Continue
rotating the engine until the advance mark is visible through the
timing hole.
An optional spring kit (PN 29014) is available for this distributor.
The kit gives you a choice of 14 different advance curve settings.
Step 2
Remove the ground cable from the battery. Remove the point wire at
the coil. Remove the point distributor.
FIGURE A
BUTTON HEAD SCREW, 3 PLACES
SHUTTER WHEEL
UNILITE® MODULE
O-RING
THRUST WASHER
GEAR
ROLL PIN
TOP
.010" END PLAY
HOUSING ASSEMBLY
GROMMET
ADVANCE ASSEMBLY
INCLUDES YH ADVANCE
AND DISTRIBUTOR SHAFT
1
Step 3
Remove the top from the Mallory distributor by removing the three screws.
Rotate the shaft until the arrow on the shutter wheel points approximately at
the arrow on the housing. Install the Mallory distributor in the engine. The slot
in the top of the housing will clear the cylinder fins.
FIGURE B
Step 4
Install a 1966-69 distributor clamp. Do not tighten the clamp at this time.
Step 5
Turn the shutter wheel by hand to test the advance. The shutter wheel
should rotate clockwise about 10 degrees and snap back when released.
Using one hand, rotate the shutter wheel clockwise to the fully advanced
position and hold. Using your other hand, rotate the housing until the
arrow on the housing lines up with the arrow on the shutter wheel. Tighten
the distributor clamp bolt. Timing should now be close enought to start the
engine.
Step 6
Replace the Mallory top and install the three screws to hold it in place.
NOTE: The 3 holes in the housing must be aligned with the 3 holes in the top
to ensure proper placement of the UNILITE ® module. (Tech Tip: Add some
Blue Loctite to 3 screws to help prevent them from vibrating loose.)
Step 7
Connect the wires as shown in Figures C and D. Start the engine and
check the timing with a timing light. NOTE: when checking the timing,
engine RPM must be above 2000 for accurate timing results.
FIGURE C
SINGLE PLUG HEADS
GREEN
RED
BROWN
2 TO 4 OHM
GROUND
12 VOLTS FROM IGNITION SWITCH
FIGURE D
DUAL PLUG HEADS
GREEN
RED
JUMPER
BROWN
1 TO 2 OHM
1 TO 2 OHM
GROUND
12 VOLTS FROM IGNITION SWITCH
MALLORY IS A DIVISION OF PRESTOLITE PERFORMANCE
10601 MEMPHIS AVE #12, CLEVELAND, OH 44144
216.688.8300
FAX 216.688.8306
www.malloryperformance.com
2
FORM #1411
(REV. D) 8/08
Made in U.S.A.
Printed in U.S.A.