Mechanical Governor; General Information; Speed Regulation - Briggs & Stratton Twin Cylinder L-Head Repair Manual

MECHANICAL GOVERNOR

General Information

The purpose of the governor is to maintain, within certain limits, a desired engine speed, even though loads may vary.
The governor spring tends to pull the throttle open. The force of the counterweights, which are operated by centrifugal
force, tends to close the throttle. The engine speed at which these two forces balance is called the governed speed.
To comply with specific top governed speed limits, Briggs & Stratton supplies manufacturers with engines having an
adjustable top speed limit, which is set to equipment manufacturers' specifications.
If a governor spring must be replaced, consult the appropriate Illustrated Parts Lists. Choose the proper governor springs
by engine type number.
CAUTION: AFTER A new governor spring is
installed, check engine top governed speed
with an accurate tachometer.
The governed speed on Twin II engines can be varied
by changing governor springs or hole location,
NO TAG.
NOTE: If Top No Load adjustment exceeds ± 100
RPM, the governor spring must be
changed.
The governed speed on Pre-Twin II engines can be
varied by changing governor spring tension and hole
location, NO TAG.

Speed Regulation

Remote governor controls (supplied by equipment
manufacturer) control engine speed by increasing or
decreasing tension on governor spring(s) to obtain
desired engine speed, Fig. 3.
2
4
#1 HOLE
NORMAL
GOVERNOR
SPRING HOLE
Ï Ï Ï Ï Ï Ï Ï
Ï Ï Ï Ï Ï Ï Ï
Ï Ï Ï Ï Ï Ï Ï
Ï Ï Ï Ï Ï Ï Ï
#2 HOLE
FOR GENERATOR
APPLICATION
Fig. 1 – Governor Spring, Twin II
(Type Nos. 1100 & Above)
GOVERNOR
LEVER
2700 TO 3100 RPM
Fig. 2 – Governor Spring Position, Pre-Twin II
(Type Nos. Below 1100)
Fig. 3 – Remote Governor Control
TOP NO LOAD
ADJUSTMENT
SCREW – NOT TO
EXCEED ±100 RPM
GOVERNOR
SPRING
3900 TO 4000 RPM
3700 TO 3800 RPM
3400 TO 3600 RPM
3200 TO 3300 RPM