Generac Power Systems GTH760, Service Manual

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Figure 3-19. Rotate The Diaphragm To Align the
Cover Screw Holes
Figure 3-20. Install Primary Spring, Primary Cover and Screws
9. Place secondary valve spring (5/16” dia. x 5/8’ long) in
spring recess near secondary orifice. Replace secondary
lever, pivot pin, 1.19” long, and two screws, 10-32 x
0.310”. Make sure the spring fits over the spring boss on
the secondary lever. Tighten screws evenly to 30 in. lbs.
±3 in. lbs. (3.39 Nm ± 0.339 Nm). See Figure 3-22.
10. The secondary lever (except for the bent tail tip) should be
level or flush with the top of casting. Bend tail end of lever
if necessary but do not use excessive force on the rubber
valve against the orifice. See Figure 3-22.
11. The secondary lever has a soft valve surface on an alumi-
num insert which must be swiveled into flat contact with
the orifice. Place a pointed instrument in the top indenta-
tion of the valve. Apply slight downward pressure and with
a gentle rotary motion, swivel the valve into flat contact
with the orifice. These valve inserts are not sold separately
but are crimped at the factory with proper tension to allow
movement but still hold their position. See Figure 3-23.
Figure 3-21. Install Secondary Valve Spring,
Lever and Pivot Pin
Figure 3-22. Make Sure Secondary Lever is Flush
With Top of Casting
12. Attach primary pressure gauge at the primary pressure test
port opening. See Figure 3-24.
13. Attach air pressure hose to the regulator fuel inlet
with approximately 100 psi, ±10 psi air pressure. See
Figure 3-25.
14. Slowly depress the secondary lever bent tail end until you
are able to detect flow out of the secondary orifice. Let the
lever then slowly return to the closed position. Observe the
primary pressure reading on the installed gauge. It should
be between 0.8 and 2.5 psi. If it is not, recheck your work
in the primary fuel section. See Figure 3-26.
3-8
SeCTIoN 3: CArbureTIoN ANd Fuel SYSTeM