Owner`s manual

Hydro-Hot Hydronic Heating System Shop Manual 07/03
R
Page 58
Section 8: Diesel-Burner Service, Maintenance, and Repair Information
Replacement Procedure:
1. Locate and disconnect the C-Plug Harness wires that connect to the
Flame Sensor and the Fuel Solenoid, reference Figures 3, 15, and
18. Also, disconnect the Ignition Cables from the Ignition Elec-
trodes, reference Figures 16 and 19.
2. Remove the Retaining Clip that secures the Photo Disc in place,
reference Figure 19. Gently lift the Photo Disc (with Flame Sensor
attached) so that it releases from the Nozzle Stand and the Ignition
Electrodes, reference Figures 16 and 19.
3. Clamp off both the Fuel Supply and Return Lines from the Diesel-
Burner Head, reference Figures 19 and 22. Loosen the Supply and
Return Banjo Bolts to remove the Fuel Supply and Return Pipes
(with the fuel lines attached) from the Fuel Pump, reference Figures
19 and 22. Also, disconnect the High Pressure Fuel Pipe from both
the Fuel Pump and the Nozzle Stand, reference Figures 19 and 22.
Discard the High Pressure Fuel Pipe, Gasket Rings, Banjo Bolts,
and Grommets, as replacements are provided in the new Fuel Pump
Kit (Part No. WPX-502-05A).
4. Remove the four Nozzle Stand Plate Screws that secure the Nozzle
Stand Plate in place, reference Figure 19. Remove the Nozzle
Stand Plate by pulling on the Nozzle Stand until the plate releases
from the cast-aluminum Blower Casing, reference Figures 13 and
19.
5. Remove the two Pump Mounting Screws that secure the Fuel Pump
in place, reference item 70 of Figure 22. Turn the Nozzle Stand
Plate over and remove the Snap Ring from the Fuel Pump shaft,
using snap ring pliers, reference item 89 of Figure 22. Remove the
nylon Drive Gear and then the Fuel Pump, reference items 88 and
72 of Figure 22.
6. Attach the new Fuel Pump to the Nozzle Stand Plate with the two
Pump Mounting Screws. Turn the Nozzle Stand Plate over to
install the nylon Drive Gear on the Fuel Pump's shaft and secure in
place with the Snap Ring. Dab the teeth of the nylon Drive Gear
with white lithium grease (Isoflex LDS-18 is recommended).
NOTES:
A: Do not adjust the Fuel Pressure Regulator of the new Fuel Pump, as
it has been factory preset.
B: Inspect the nylon Drive Gear's cavity inside the cast aluminum
Blower Casing for fuel stains. If fuel stains are present, a replace-
ment of the Bearings and/or the entire Bower Casing may be
necessary (leaking fuel could cause Bearing seizure, resulting in
potential damage to the internal bore / bearing cavity of the Blower
Casing). Reference Section 8.9, Page 60 for the Bearing "Replace-
ment Procedure" and contact our Technical Department at 1-800-
685-4298 for additional assistance.
7. Fit the Nozzle Stand Plate inside the cast-aluminum Blower Casing
Fuel Pump,
continue
d