Adjust Valve Lash; Electronic Governor System - Briggs & Stratton FORTRESS Series Installation And Operation Manual

12. Install the oil filter by hand until the gasket contacts the oil
filter adapter, then tighten the oil filter ½ to ¾ turn.
13. Add the required amount of oil to bring the level up to, but
not over, the "FULL" mark on the dipstick. Install the oil
filler cap and wipe up any spilled oil.
14. Connect the negative (-) cable at the battery.
15. Install the 15 Amp fuse into the fuse holder at top of the
control box.
16. Install the roof.
17. Restore utility power to the generator.
18. Push the ON/OFF Switch on the side of the generator to
the "ON" (I) position.
19. Set the generator mode to AUTO.
Engine Oil
The engine is filled with synthetic oil (API SJ/CF 5W-30).
This allows for system operation in the widest range of
temperature and climate conditions.
We recommend the use of Briggs & Stratton
5W-30 full synthetic engine oil. Other high-quality detergent
oils are acceptable if classified for service SJ or higher. Do
not use special additives.

Adjust Valve Lash

The valve lash must be checked every 100 hours of
operation. Measure the valve clearance with the engine cold.
To adjust the valve lash, proceed as follows:
1. Push the ON/OFF Switch on the side of the generator to
the "OFF" (0) position.
2. Remove utility power to the generator to de-energize the
battery charger.
3. Remove the roof.
4. Remove the 15 Amp fuse from the fuse holder at top of
the control box.
5. Disconnect the negative (-) cable at the battery.
6. Remove the two fasteners from the valve cover to gain
access to valves.
7. Remove spark plugs to ease manual rotation of engine
crankshaft.
8. Turn crankshaft counterclockwise until the piston is at
Top Dead Center on the compression stroke.
9. Put a narrow screwdriver or rod into the spark plug
hole as a gauge. Then, slowly turn the crankshaft
counterclockwise until the piston moves down the bore by
1/4" (0.635 cm).
10. For the Model 38 Engine:
®
80028446 SAE
Note: Synthetic oil meeting ILSAC
GF-2, API certification mark and API
service symbol with "SJ/CF ENERGY
CONSERVING" or higher, is an
acceptable oil at all temperatures.
Use of synthetic oil does not alter
required oil change intervals.
• Use a feeler gauge (A) to measure the valve
clearance.
• To adjust the clearance, loosen the lock nut (B) then
turn the adjusting screw (C) to get the clearance
measurements that follow:
• Intake: 0.005 in. (0.13 mm)
• Exhaust: 0.008 in. (0.20 mm).
• When the clearance is set correctly, hold the
adjusting screw while torquing the lock nut to 70 in/
lbs. (8 Nm).
• Refer to appropriate engine service manual
11. Assemble the valve cover by carefully aligning cover and
fastener holes. Tighten the valve cover fasteners to 35 in/
lbs (3.9 Nm).
12. Do the steps again for the other valve.
13. Connect the negative (-) cable at the battery.
14. Install the 15 Amp fuse into the fuse holder at top of the
control box.
15. Install the roof.
16. Restore utility power to the generator.
17. Push the ON/OFF Switch on the side of the generator to
the "ON" (I) position.
18. Set the generator mode to AUTO.

Electronic Governor System

The engine electronic governor system allows for improved
control and increased generator performance compared
to mechanically governed systems. The result is a smooth
steady-state operation without the "hunting" common to
many mechanical governors. The system also reduces
speed variations under engine loading and unloading and
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