Table 3-3. Unit Maintenance Troubleshooting Continued
TEST OR INSPECTION
Step 8. Check igniter assembly. Remove igniter from burner head. Inspect for fouling
and burned electrode (1). End of electrode must be flush with face (2) to
0.010 inch (0.254 mm) underflush.
If badly fouled or burned, replace igniter.
Step 9. Test transformer assembly.
When checking spark, do not allow spark gap
to exceed 1/8 inch (3.175 mm). Larger gap
will cause excessively high potential buildup
resulting in insulation breakdown either in-
ternally or in ignition cable.
Disconnect fuel pump cable from EXTERNAL FUEL PUMP RECEPTACLE,
Close shutoff valve at fuel container.
Disconnect ignition cable (1) from
igniter assembly. Position spring (2) at tip of cable not more than 1/8 inch
(3.175 mm) from grounded surface (3). Place HEATER-OFF-FAN switch in
HEATER position, If no spark is observed, inspect connector (4) for signs of
burning or improper installation.
If defective, replace kitted parts as described in REMOVE/lNSTALL/TEST
REPAIR IGNITION TRANSFORMER AND CABLE, page 3-110.