FORM 160.77-O1
ISSUE DATE: 10/22/2020
JOHNSON CONTROLS
32
SECTION 4 - TROUBLESHOOTING
Oil Pump Vibrates
Or Is Noisy
Oil pump vibrates or is extremely noisy
with some oil pressure when pressing
OIL PRESSURE display key.
When oil pump is run
without an oil supply
it will vibrate and be-
come extremely noisy.
Oil not reaching pump
suction inlet in sufficient
quantity.
Check oil level.
Worn or failed oil pump.
Repair/Replace oil pump.
Reduced Oil
Pump Capacity
Oil pump pumping capacity.
Excessive end clearance
pump. Other worn pump
parts.
Inspect and replace worn
parts.
Partially blocked oil supply
inlet.
Check oil inlet for blockage.
Symptom:
Oil Pressure
Gradually
Decreases (Noted
by Observation of
Daily Log Sheets)
When oil pump VSD frequency in-
creases to 55 + hz to maintain target oil
pressure.
Oil filter is dirty.
Change oil filter.
Symptom:
Oil Return System
Ceases To Return
An Oil/Refrigerant
Sample
Oil refrigerant return not functioning.
Filter-drier in oil return
system dirty.
Replace old filter-drier with
new.
Jet or orifice of oil return jet
clogged.
Remove jet, inspect for dirt.
Remove dirt using solvent
and replace.
Symptom:
Oil Pump Fails
To Deliver Oil
Pressure
No oil pressure registers when pressing
OIL PRESSURE display key when oil
pump runs.
Faulty oil pressure transducer.
Faulty wiring/connectors.
Replace oil pressure trans-
ducer.
TABLE 3 -
OPERATION ANALYSIS CHART (CONT'D)
