Mallory Ignition А556 User Manual

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 DISTRIBUT OR. BECAUSE THE UNILITE® MODULE USED WITH THIS DISTRIBUTOR REQUIRES 7-16 VOLTS, A 12 VOLT ELECTRICAL SYSTEM IS ALSO REQUIRED.

GENERAL INFORMATION

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.

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.

An optional spring kit (PN 29014) is available for this distributor. The kit gives you a choice of 14 different advance curve settings.

INSTALLATION

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.

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.

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

TOP

GROMMET

THRUST WASHER GEARO-RING

ROLL PIN

.010" END PLAY

HOUSING ASSEMBLY

ADVANCE ASSEMBLY INCLUDES YH ADVANCE

AND DISTRIBUTOR SHAFT

Step 3

SINGLE PLUG HEADS

GREEN RED

2 TO 4 OHM

BROWN

GROUND

12 VOLTS FROM IGNITION SWITCH

DUAL PLUG HEADS

GREEN

JUMPER

12 VOLTS FROM IGNITION SWITCH

RED

BROWN

GROUND

1 TO 2 OHM 1 TO 2 OHM

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 ﬁ ns.

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 B

FIGURE C

FIGURE D

MALLORY IS A DIVISION OF PRESTOLITE PERFORMANCE 10601 MEMPHIS AVE #12, CLEVELAND, OH 44144

216.688.8300 FAX 216.688.8306 www.malloryperformance.com

FORM #1411

(REV. D) 8/08

Made in U.S.A.

Printed in U.S.A.