Removing And Disassembly; Service Checks - BENDIX TU-FLO 700 COMPRESSOR Manual

Every 6 months, 1800 operating hours or after each
50,000 miles:
Remove the discharge head fittings and inspect the
compressor discharge port and discharge line for excessive
carbon deposits. If excessive buildup is noted in either, the
discharge line must be cleaned or replaced and the
compressor checked more thoroughly, paying special
attention to the air induction system, oil supply and return
system, and proper cooling. If necessary, repair or replace
the compressor. Check for proper belt and pulley alignment
and belt tension. Adjust if necessary, paying special attention
not to over tighten the belt tension. Check for noisy
compressor operation, which could indicate a worn drive
gear coupling or a loose pulley. Adjust and/or replace as
necessary. Check all compressor mounting bolts and
retighten evenly if necessary. Check for leakage and proper
unloader mechanism operation. Replace if defective in any
way.
Every 24 months, 7200 operating hours or after each
200,000 miles:
Perform a thorough inspection as indicated below and
depending upon the results of this inspection or experience,
disassemble the compressor, clean and inspect all parts
thoroughly, repair or replace all worn or damaged parts using
only genuine Bendix replacements or replace the
compressor with a genuine Bendix remanufactured unit.
Important: Should it be necessary to drain the engine cooling
system to prevent damage from freezing, the cylinder head
of the compressor must also be drained.
GENERAL SERVICE CHECKS
INSPECTION
It is of the utmost importance that the compressor receives
a clean supply of air. The air strainer must be properly
installed and kept clean. If the compressor intake is connected
to the engine air cleaner, supercharger, etc., these
connections must be properly installed and maintained.
Check the compressor mountings to be sure they are secure.
Check the drive for proper alignment, belt tension, etc.
Inspect the oil supply and return lines. Be sure these lines
are properly installed and that the compressor is getting the
proper supply of oil, and just as important, that the oil is
returning to the engine. Check the coolant lines to and from
the compressor and see that the cooling fins on the
crankcase are not clogged with dirt, grease, etc. Check the
unloader mechanism for proper and prompt operation.
OPERATING TESTS
Vehicles manufactured after the effective date of FMVSS
121, with the minimum required reservoir volume, must have
a compressor capable of raising air system pressure from
6
85-100 P.S.I. in 25 seconds or less. This test is performed
with the engine operating at maximum governed speed. The
vehicle manufacturer must certify this performance on new
vehicles with appropriate allowances for air systems with
greater than the minimum required reservoir volume.
AIR LEAKAGE TESTS
Leakage past the discharge valves can be detected by
removing the discharge line, applying shop air back through
the discharge port and listening for escaping air. Also, the
discharge valves and the unloader pistons can be checked
for leakage by building up the air system until the governor
cuts out, then stopping the engine. With the engine stopped,
listen for escaping air at the compressor intake. To pinpoint
leakage if noted, apply a small quantity of oil around the
unloader pistons. If there is no noticeable leakage at the
unloader pistons, the discharge valves may be leaking. If
the compressor does not function as described above, or
leakage is excessive, it is recommended that it be returned
to the nearest authorized Bendix Distributor for a factory
remanufactured compressor. If this is not possible, the
compressor can be repaired using genuine Bendix
replacement parts, in which case, the following information
should prove helpful.

REMOVING AND DISASSEMBLY

REMOVING
These instructions are general and are intended to be a
guide, in some cases additional preparations and precautions
are necessary. Chock the wheels of the vehicle and drain
the air pressure from all the reservoirs in the system. Drain
the engine cooling system and the cylinder head of the
compressor. Disconnect all air, water and oil lines leading
to and from the compressor. Remove the drive gear(s) or
pulley from the compressor crankshaft using a gear puller.
Inspect the pulley or gear and associated parts for visible
wear or damage. Since these parts are precision fitted, they
must be replaced if they are worn or damaged.
DISASSEMBLY
GENERAL
Remove road dirt and grease from the exterior of the
compressor with a cleaning solvent. Before the compressor
is disassembled, the following items should be marked to
show their relationship when the compressor is assembled.
Mark both the front and rear end cover in relation to the
crankcase. Mark the drive end of the crankshaft in relation
to the front end cover and the crankcase. Mark the cylinder
head in relation to the block and the block in relation to the
crankcase. Mark the base plate or base adapter in relation
to the crankcase.