Vanguard BIG BLOCK M540000, Repair Manual, Page: 10 / 168

GENERAL INFORMATION
Engine Identification
See Figure 1. On horizontal shaft engines, the engine model,
type, trim and serial number are etched on the oil fill valve
cover on the starter motor side of the engine. Vertical shaft
engines may have the model, type, trim and serial number
etched on the valve cover on the oil filter side of the engine.
Older Big Block engines may have the model, type, trim
and serial number etched on the base of the crankcase.
Additionally, a Power Code decal, mounted on the engine
blower housing, provides the serial number, model number,
and a QR code for easy access to the Power Portal.
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Fuel Recommendations
Fuel must meet these requirements:
• Clean, fresh, unleaded gasoline.
• A minimum of 87 octane/87 AKI (91 RON). High
altitude use, see below.
• Gasoline with up to 10% ethanol (gasohol) is permitted.
NOTICE
Do not use unapproved gasoline, such as E15 and E85.
Do not mix oil in gasoline or change the engine to operate
on alternate fuels. Use of unapproved fuels could result in
damage to engine components, which will not be repaired
under the warranty.
To protect the fuel system from gum formation, and
corrosion, mix an alcohol-free fuel stabilizer and ethanol
treatment into the fuel. Refer to the Storage section. All fuel
is not the same. If start or performance problems occur,
change fuel providers or brands. This engine is certified
to operate on gasoline. The emissions control system for
carbureted engines is EM (Engine Modifications). The
emissions control systems for engines with electronic fuel
injection are ECM (Engine Control Module), MFI (Multiport
Fuel Injection), TBI (Throttle Body Fuel Injection) and if
equipped an O2S (Oxygen Sensor).
High Altitude
At altitudes over 5,000 feet (1524 meters), a minimum 87
octane/87 AKI (91 RON) gasoline is permitted.
For carbureted engines, high altitude adjustment is
required to maintain performance. Operation without this
adjustment will cause decreased performance, increased
fuel consumption, and increased emissions. Contact
a Briggs & Stratton Authorized Service Dealer for high
altitude adjustment information. Operation of the engine at
altitudes below 2,500 feet (762 meters) with the high altitude
adjustment is not recommended.
For Electronic Fuel Injection (EFI) engines, no high altitude
adjustment is necessary.
Fuel Recommendations - Gaseous Engines
Fuel must meet these requirements
• Use clean, dry fuel, free of moisture or any particulate
material. Fuels used outside the recommended values
can cause performance problems.
• On engines that operate on LPG, commercial grade
HD5 LPG is recommended. Recommended fuel
composition is fuel with a minimum fuel energy of 2500
BTU's/ft³ with maximum propylene content of 5% and
butane and heavier gas content of 2.5% and minimum
propane content of 90%.
NG or LPG engines are certified to operate on natural or
liquid propane gas. The emissions control system for this
engine is EM (Engine Modifications).
Oil Recommendations
Oil Capacity : Refer to SECTION 9 - SPECIFICATIONS .
We recommend the use of Briggs & Stratton
®
Warranty
Certified oils for best performance. Other high-quality
detergent oils are permitted if classified for service SF, SG,
SH, SJ or higher. Do not use special additives.
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