1.0
DETROIT DIESEL 53
SHOP NOTES - TROUBLE SHOOTING - SPECIFICATIONS -
S E R V I C E TOOLS
SHOP NOTES
TEFLON WRAPPED PIPE PLUGS
2. Start the tape one or two threads from the small or
Pipe plugs with a baked teflon coating are available
leading edge of the plug. joining the tape together
for service. However, pipe plugs can be hand wrapped
with an overlap of approximately 1/8"
satisfactorily with teflon tape to provide a better seal
and facilitate plug removal. When a teflon wrapped
3. Wrap the tape tightly in the same direction as you
plug is installed, it is extremely important that the
would turn a nut. The tape must conform to the
specified torque not be exceeded.
configuration of the threads (be pressed into the minor
diameter of the threads) without cutting or ripping the
Hand wrap a pipe plug with teflon tape as follows:
tape.
1. Be sure the pipe plug is thoroughly clean and dry
4. Hand tighten and hand torque the pipe plug and do
prior to applying the teflon tape. All dirt, grease, oil
and scale must be removed.
not exceed the specified torque. Do not use power tools.
CHECKING BEARING CLEARANCES
A strip of soft plastic squeezed between the crankshaft
journal and the connecting rod bearing or main
bearing may be used to measure the bearing
clearances.
The strip is a specially molded plastic "wire"
manufactured commercially and is available in three
sizes and colors. Type PC-1 (green) has a clearance
range of 001" to ,003", type PR-1 (red) has a range
of ,002" to .006" and type PB-1 (blue) has a range of
,004" to ,009"
The plastic strip may be used for checking the bearing
clearances as follows:
I. Remove the bearing cap and wipe the oil from the
bearing shell and the crankshaft journal.
NOTE: When checking the main bearing
clearances with the engine in a position where
the main bearing caps are supporting the
weight of the crankshaft and the flywheel, an
erroneous reading, due to the weight of the
crankshaft and flywheel, can be eliminated by
supporting the weight of the crankshaft with a
jack under the counterweight adjoining the
bearing being checked.
2. Place a piece of the plastic strip the full width of the
bearing shell, about 1/4" off center (Fig. 1).
3. Rotate the crankshaft about 30 from bottom dead
Fig. 1 Using Plastic Strip to Measure
center and reinstall the bearing cap. Tighten the bolts
Bearing-to-Crankshaft Clearance
to the specified torque.
SEC. 1.0 Page 1
April. 1974
