MTD 61 series, Shop Manual

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Introduction
7
Air filter
The main function of the air filter is to trap air borne par-
ticles before they reach the carburetor that can cause cat-
astrophic internal engine damage.
MTD vertical shaft engines are equipped with one
of two different air filters. The first is a rectangular paper
pleated filter that may or may not have a foam pre-cleaner.
The second is an oval foam filter. See Figure 1.3.
• Air filters used on the MTD engine are designed
to prevent particles larger than 3-5 micron from
passing through into the engine.
• The filter should be checked on a regular basis
possibly several times in a season.
• Typically an air filter should be changed before
every season.
• If a foam air filter or pre-cleaner is dirty, but not
in bad of condition, it can be cleaned and
reused. The paper pleated filters can be shaken
or lightly tapped to free the debris from the filter.
NOTE: Never use compressed air on a paper air filter. Compressed air will remove the tiny fibers that are used
to catch the dirt in the air. Without these fibers the filter is useless.
• Foam filters or pre-cleaners can be washed in warm soapy water.
NOTE: When drying a foam filter either squeeze it inside of a paper towel or let it air dry. DO NOT wring it.
Wringing the foam filter will cause damage to the foam.
NOTE: On foam filters, dry the filter throughly then apply a couple of drops of motor oil. Gently work the oil
through the filter before installing it.
NOTE: Always check with factory specification prior to servicing/replacing any engine components.
NOTE: Do not oil the foam pre-cleaner. The paper filer will absorb the oil and it will become plugged.
Figure 1.3
Foam filter
Paper-pleated element
Foam pre-cleaner