Servicing The Spark Plugs - Toro 74291 Operator's Manual

1. Oil filter
2. Adapter gasket
3. Pour new oil in through the center hole of the filter.
Fill it up to the bottom of the threads inside.
4. Allow the filter material to absorb the new oil for
1 to 2 minutes.
5. Apply a thin coat of new oil to the rubber gasket on
the replacement filter (Figure 30).
6. Install the replacement oil filter to the filter adapter,
turn the oil filter clockwise until the rubber gasket
contacts the filter adapter, then tighten the filter an
additional 2/3 to 1 turn (Figure 30).
7. Fill the crankcase with the proper type of new oil;
refer to Servicing the Engine Oil.
8. Run the engine for about 3 minutes, stop the engine,
and check for oil leaks around the oil filter.
9. Check the engine oil level and add oil if needed.

Servicing the Spark Plugs

Ensure that the air gap between the center and side
electrodes is correct before installing the spark plug.
Use a spark plug wrench for removing and installing the
spark plugs and a gapping tool/feeler gauge to check and
adjust the air gap. Install a new spark plugs if necessary.
Type: Champion® RC12YC, Champion® Platinum
3071 or equivalent
Air Gap: 0.030 inch (0.76 mm)
Checking the Spark Plugs
Service Interval: Every 200 hours
1. Look at the center of the spark plugs (Figure 31).
If you see light brown or gray on the insulator, the
engine is operating properly. A black coating on the
insulator usually means that the air cleaner is dirty.
Figure 30
3. Adapter
1. Center electrode insulator
2. Side electrode
Important: Always replace the spark plugs
when it has a black coating, worn electrodes,
an oily film, or cracks.
2. Check the gap between the center and side electrodes
(Figure 31). Bend the side electrode (Figure 31) if
the gap is not correct.
Removing the Spark Plugs
1. Disengage the PTO and set the parking brake.
2. Stop the engine, remove the key, and wait for all
moving parts to stop before leaving the operating
position.
3. Disconnect the wires from the spark plugs
(Figure 32).
1. Spark-plug wire/spark plug
4. Clean around the spark plugs to prevent dirt from
falling into the engine and potentially causing
damage.
5. Remove the spark plugs and the metal washers.
29
Figure 31
3. Air gap (not to scale)
Figure 32