Mallory Ignition 642, 643, 644 User Manual

INSTALLATION

INSTRUCTIONS

ADJUSTABLE PROPORTIONAL RPM LIMITER

PART NOS. 642, 643, AND 644

Mallory's Proportional RPM Limiter functions as an engine protection device. As the RPM setting is reached, the RPM Limiter will cut off the spark. This protects your engine from runaway and damage.

This limiter can be used in many different applications:

•

Marine Use

When a marine engine is under a heavy load and slips out of gear, loses a propeller, breaks a drive shaft, or the propeller loses contact with the water, engine runawa y occurs.The limiter limits RPM and protects the engine.

•

Racing

Mallory's RPM Limiter prevents engine damage from missing a shift at high RPM.

•

Industrial Use

Runaway engines are common in industrial applications. Mallory's RPM Limiter eliminates engine damage from over-revving.

INSTALLATION PROCEDURE

1. Install the Proportional RPM Limiter on the inside of the firewall or a convenient location under the dash. Mount the dial in a visible location on the dash.Use the metal screws supplied with the limiter.

2. When performing the following operations, cut all leads as short as possible, leaving enough slack to absorb engine vibration. Solder and tape all connections.

3. Run the green and black wires through any existing hole in the firewall.If there is not a convenient hole , drill a 3/16" or larger hole in the firewall.Be sure to remove all burrs and sharp edges.

4. Connect the green wire to the coil negative (–) terminal.

5. Connect the black wire to a clean ground on the engine block.

6. Connect the red wire to a fused, positive (+) po w er source , pref erably one that turns on and off with the ignition switch.

NOTES

1. 12 volt negative ground only.

2. Actual limiting RPM may be several hundred RPM less than the dial indication, depending on the condition of your ignition system components.

3. Critical limit adjustment should be made using an accurate tachometer as a reference.

FORM 41656 (REV. B) 7/98 MADE IN U.S.A. PRINTED IN U.S.A.

550 Mallory Way, Carson City, NV 89701

(775) 882-6600