Bendix Commercial Vehicle Systems TP-2 TRACTOR PROTECTION VALVE 3/04 - Manual (Page 3)

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9. With soap solution:
A. Coat emergency line coupling. Leakage of a 1"
bubble in 5 seconds is permissible (100 SCCM).
B. Coat service line coupling. Make and hold a full hand
or foot valve application. Leakage of a 1" bubble in 5
seconds is permissible (100 SCCM).
10. Connect the coupling and test gauge to the emergency
line hose coupling. Place the tractor protection control
valve to “Normal” position. (If necessary, re-start engine
and build system pressure.) With ignition switch “on”
slowly drain tractor air brake system observing that low
pressure indicator occurs at prescribed pressure (normally
at approximately 60 psi) observe that the emergency
Iine will be vented by the tractor protection valve between
45 to 33 psi (test gauge will drop to 0 psi.)
If the TP-2 ™ tractor protection valve does not function as
described or if leakage is excessive, it is recommended
that it be replaced with a new or remanufactured unit, or
repaired with genuine Bendix parts, available at Bendix
outlets.
REMOVING AND INSTALLING
REMOVING
1. Block and/or hold vehicle by a means other than air
breaks. Drain air system reservoirs.
2. Identify lines and hoses so that correct lines are
reconnected to proper ports when reinstalling.
3. Remove lines; remove valve.
INSTALLING
1. Mount valve, checking to make certain control cap is
properly positioned. If it is necessary to re-position cap,
refer to No. 3 of “Assembly Instructions.”
2. Connect lines making certain proper lines are
connected to correct ports.
DISASSEMBLY
Important: Mark position of control port and tractor
emergency port location in relation to body in such a manner
that mark will not be obliterated during cleaning of parts.
Three (3) springs in valve should be carefully marked as to
their proper location in valve as valve is disassembled.
1. Remove four (4) cap screws (1) Figure 1, lock washers,
and cover (2) from valve.
2. Remove emergency valve (3) and emergency valve
spring (4) from cover.
3. Remove valve seat (5) service and exhaust valve (6),
valve retainer (7), spring (8).
4. Remove o-rings (9), (10), and (11).
5. Remove cap nut (12) and control cap. (13).
6. Remove exhaust valve plunger and diaphragm assembly
from body. (14).
7. Remove exhaust plunger spring (15) from body.
8. Inspect bores in valve body to be sure they are not
damaged or out of round. Clean body, control cap and
cover.
CLEANING AND INSPECTION
1. Clean all metal parts in mineral spirits and dry them
completely.
2. Inspect all parts for excessive wear or deterioration.
Inspect valve seats for nicks or burrs. Check the valve
spring for cracks or corrosion.
3. Inspect the bores of the valve housing for deep scuffing
or gouges.
Replace all parts that were discarded and any parts not
found to be serviceable during inspection, using only genuine
Bendix replacement parts.
ASSEMBLY
Before assembling the TP-2 ™ valve, lubricate all o-rings,
o-ring grooves, body bores and rubbing surfaces with Bendix
silicone lubricant (Pc. No. 291126) or equivalent.
NOTE: When using pipe thread sealant during assembly
and installation, take particular care to prevent the
sealant from entering the valve itself. Apply the
sealant beginning with the second thread back from
the end.
1. Place in vise with control cap end up. Install o-ring (16)
in groove in the stem of the exhaust valve plunger and
diaphragm assembly (14).
2. Install exhaust plunger spring (15) in valve body and
install exhaust plunger and diaphragm assembly (14).
IMPORTANT: Both sides of diaphragm and clamping
surfaces of body and control cap must be
free of grease. Plunger should be a neat
sliding fit in bore.
3. Position control cap (13) and cap nut (12). Position control
cap to desired port angle (as marked during
disassembly). Install a short (4-6") 1/4" pipe nipple in
control port of cap. Apply pressure firmly on cap, holding
in position with pipe nipple and firmly tighten cap nut to
approximately 50 ft. lbs.
It is important that the cap not be allowed to turn while
tightening the cap nut. Remove pipe nipple from control
port.
4. Place valve in vise with control cap down.
5. Install o-ring (10) in valve body (smaller of two o-rings).