Suitable Replacement McCulloch MAC 120 Carburetor Kit
Performance Parts Supply carb kits meet or exceed OEM specifications for McCulloch MAC 120 carburetor kit parts and they cost less than OEM kits while maintaining excellent quality and durability. You can quickly buy our suitable replacement McCulloch MAC 120 Chainsaw Carburetor Kit for sale in our online store and get it shipped fast.
McCulloch MAC 120 Carburetor Kit - General Carb Kit Info
has two different sides. First, the fuel pump side of the carburetor
pumps fuel from the fuel tank through the fuel line to the metering
side of the carburetor. Second, the metering side of the carburetor
supplies fuel to the jets in the carburetor so the saw idles
properly. Additionally, this side allows the saw to accelerate to
full throttle instantly when the throttle is activated [pulled].
Finally, this side maintains fuel to the chain saw motor at full
throttle regardless of the position of the saw.
The McCulloch MAC 120 carburetor
has diaphragms and gaskets to help it pump and meter the fuel by
crankcase impulse. Every time the piston goes up and down, it creates
vacuum and pressure in the crankcase. The carburetor uses this pulse
via a pulse line connected to the crankcase or through the carburetor
intake to get the pulse needed to properly make the carburetor
On the metering
lever side of the McCulloch MAC 120 carburetor, there is a diaphragm and gasket with a
cover plate screwed to the carburetor. The metering diaphragm
controls the amount of fuel allowed to enter the metering lever side
of the carburetor. The diaphragm is either connected or just touching
the fulcrum [meter lever] and when fuel exits the metering side of
the carburetor through the jets in the carburetor, atmosphere
pressure [14.7 psi] pushes the diaphragm in letting more fuel in. As
the fuel rises to fill the metering lever side of the McCulloch MAC 120 carburetor, the
inlet needle valve closes the fuel off from the fuel pump side of the
carburetor. The needle valve goes into the body of the carburetor and
is fastened to the metering lever fulcrum which has a spring under
the opposite side of the needle valve to keep pressure on the needle
valve when closed.
On the metering
lever side of the McCulloch MAC 120 chainsaw carburetor there are two sides, a low side and a
high side. The low side controls idle and acceleration when the saw
starts to rev up. The high side controls the amount of fuel the saw
will receive at full RPM. Some carburetors will have 2 adjusting
screws, one for the low side and one for the high side. There is
also an idle screw which makes contact with the throttle shaft to
control idle speed along with the low side of the carburetor. Note
that some carburetors have just one adjusting screw and the other
side is prefixed and non-adjustable. Some may also have no adjusting
screws [except the idle screw] to preset or pre-jet the carburetor.
Important Notice - We are not affiliated with any chainsaw manufacturers and we do not attempt to make any affiliations with them. Any manufacturer logos, model names and numbers are the sole property of their respective owners and are used here for the sole purpose of reference. We do not sell OEM chainsaw parts for any brand. We do however, offer high quality suitable replacement parts guaranteed to meet or beat OEM part specifications like our suitable replacement Chainsaw McCulloch MAC 120 Carburetor Kit we offer for sale for you to buy and put into their brand of chainsaws.