Service Manual

3-26

Digital Edition - TITAN® HD Service Manual

January 2018

Table of Contents

MAINTENANCE

Servicing the Kohler Engine (Cont.)

Checking the Spark Plug

1. Inspect the spark plug.

NOTE: If you see light brown or gray coating on the insulator, the engine is operating properly. A black

coating on the insulator usually means the air cleaner is dirty.

NOTE: Do not clean the spark plug(s). Always replace the spark plug(s) when it has: A black coating, worn

electrodes, an oily lm, or cracks.

2. Check the gap between the center and side electrodes (Figure 20).

3. Set the gap to 0.030 in. (0.76 mm).

Installing the Spark Plug

1. Tighten the spark plugs to 20 ± 2 ft-lbs. (25-30 Nm).

Figure 20