Tennant 1550, Manual

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MAINTENANCE
1550 Gas/LPG/Diesel MM283 (9--01)
3--30
ELECTRICAL SYSTEM
SPARK PLUGS
Clean or replace and adjust spark plugs after
every 200 hours of operation. A wire gauge is
best for checking the spark plug gap. A flat gauge
should not be used unless the electrode surfaces
have been been dressed with a small file to get
parallel surfaces between the center and side
electrodes. Set the spark plug gap by bending the
side electrode. All spark plugs, new or used,
should have the gaps checked and reset if
necessary.
A
B
00054
GAPPING THE SPARK PLUG
A. Spark Plug
B. Gapping Tool
The proper spark plug gap for TM27 engines
(machines below serial number 001424) is 0.035
in (0.9 mm).
The proper spark plug gap for GM engines
(machines serial number 001424 and above) is
0.040 in (1.0 mm).
To get good performance from the spark plugs,
follow these steps when installing the plugs:
1. Clean the spark plug seat in the cylinder
head.
2. Use a new seat gasket and screw the plug
in by hand.
3. Tighten the spark plugs to 22 to 28 ft lb
(30 to 38 Nm) with a socket wrench of the
correct size.
DISTRIBUTOR
The distributor operation is vital to the operation of
the engine and the following items should be
carefully inspected every 200 hours of normal
operation; however, dirt, dust, water and high
speed operation may cause more rapid wear and
necessitate more frequent inspections:
1. Remove the distributor cap. Clean the cap
and examine for cracks, carbon runners, or
corroded terminals. If the vertical faces of
the inserts are burned, install a new cap. If
the horizontal faces of the inserts are
burned, replace the cap and the rotor as this
condition is caused by the rotor being too
short.
2. Check the centrifugal advance mechanism
for “freeness” by turning the distributor shaft
in the direction of rotation and then releasing
it. The advance springs should return the
shaft to its original position.