HOW TO IDENTIFY A Tecumseh Power CARBURETOR
Tecumseh Power has a variety of carburetors. To help identify these carburetors here are some simple procedures to
follow.
DUAL SYSTEM CARBURETORS
The easiest way to identify the dual system carburetor is
by the presence of a large primer bulb located on the
side of the carburetor. The absence of adjustment
needles help to identify the carb as well. The dual
system carburetor is used on 4-cycle vertical crankshaft
rotary mower engines.
SERIES 1 CARBURETORS
Series 1 carburetors come in a variety of styles. They
are used on both 2 and 4-cycle vertical and horizontal
shaft engines in the 2 through 7 h.p. range. It is a float
style carburetor with a smaller venturi than the Series 3
and 4 carburetors. Some will have an adjustable idle
and main and others will have a fixed main with an
adjustable idle. There are also some fixed speed
applications that will only have a fixed main system and
the idle system will not be drilled.
SERIES 1 EMISSION
This carburetor is similar to the standard Series 1
carburetor. The emission equivalent has a fixed idle and
main. The idle restrictor jet will be capped to prevent
access unless the cap is removed. The fixed main jet is
part of the bowl nut. A ball plug is visible from the bottom,
which seals the passage. This carburetor also has a
serviceable main nozzle emulsion tube.
5
HOW TO IDENTIFY A Tecumseh CARBURETOR
(CONTINUED)
SERIES 2 CARBURETORS
Series 2 carburetors were used on outboard engines.
This carburetor is the same as the Series 1 with the
exception of the remote adjustable idle mixture screw,
and a built in fuel pump.
Series 2 carburetors have a built-in fuel pump consisting
of a fuel pump element which inflates and deflates with
crankcase pulsations which opens and closes two flap
valves in the fuel pump, thereby pumping fuel from a
remote tank to the carburetor float bowl.
When replacing the fuel pump element, install with the
o
slot opening at a 45 angle as illustrated. Installation in
any other position will damage the diaphragm.
SERIES 3 & SERIES 4 CARBURETORS
Series 3 and 4 carburetors are generally used on 8
through 12.5 horsepower 4-cycle engines. The venturi
size of these carburetors are larger than Series 1 and
Dual System Carburetors. The quickest way to identify
these carburetors is by the presence of bosses on each
side of the idle mixture screw.
SERIES 3 & SERIES 4 EMISSION
This carburetor is similar to the standard Series 3 &
carburetor with a few subtle differences. The emissio
equivalent has a fixed idle and main. The idle restrict
jet will be capped to prevent access unless the cap
removed. The fixed main jet is part of the bowl nut. Ab
plug is visible from the bottom, which seals the passag
This carburetor also has a serviceable main nozz
emulsion tube.
FIXED IDLE
FIXED MAIN