PROCEDURES
PAGE 1 OF 2
SUBJECT
Sealing Ring Piston Kit
For Part Number P39106
APPLICATION
Caterpillar 3406E C15/C16
FITS MODELS
P-39, P-39A, P-39B
L5322.120404
This kit contains 6 replacement slave pistons with seal rings to
improve retarding on brakes with slave bore wear.
Attention:
Sealing ring pistons are designed to stop oil bypass-
ing between the piston and bore. These replacement pistons are
unable to prevent engine damage due to piston misalignment if
excessive wear is present.
Important:
When installing a P39106 slave piston seal ring kit
into a P-39 / P-39A engine brake, it is imperative the Paclash
slave piston adjusting screws are updated to P39084 at this
time. Our P39084 adjusting screws are identifi ed by the letter
“P” engraved or stamped on the end. Installation of a P39106
kit without P39084 adjusting screws will subject the housing
to higher internal pressures and housing failure may result. All
P-39B engine brakes incorporate the P39084 adjusting screws
from the factory.
Removal Of The Housings From The Engine
1
Clean the engine around all three valve covers and remove.
2
Loosen the slave piston adjusting screw lock-nuts.
3
Remove the wires at the solenoids.
4
Remove the nut on the support stud, then evenly remove the 4 hold down capscrews.
5
Remove all three housings from the engine.
Disassembly And Assembly Of The Brake Housings
1
Place the housings on a clean work bench.
2
Remove the slave piston adjusting screws and inspect the plungers for spring pressure or damage.
3
Slave Piston Removal
Use caution
and wear eye protection, as the retaining washers are under spring pressure!
Use a “C” clamp and a socket slightly larger than the O.D. of the slave link. Position the socket over the
link. Using the “C” clamp, compress the retainer just enough to remove the spring pressure, then remove
retaining ring. Slowly back off the “C” clamp. Remove the retaining washer, spring, and slave piston.
Discard the slave pistons only.
3
Apply clean engine oil to the replacement piston and rings and install in housing bore.
4
Apply clean engine oil to the contact surface of the slave piston to slave link.
5
Install a slave piston return spring in each.
6
Install a retaining washer in each with the stepped side towards the spring.
7
Using a “C” clamp and a socket in the reverse procedure as above, install the retaining rings.
Make sure retaining rings are seated in the groove.
8
Reinstall slave piston adjusting screws and install housings on the engine as per Pacbrake Installation
Manual.
