A/C - Moaning Noise At Idle When Hot

Article No. 90-18-8
^ AIR CONDITIONING - 5.0L - COMPRESSOR MOAN AT IDLE SPEED IN HIGH AMBIENT TEMPERATURE

^ NOISE - "MOAN" FROM A/C COMPRESSOR - 5.0L - AT IDLE SPEED IN HIGH AMBIENT TEMPERATURE
FORD: 1989-90 CROWN VICTORIA

LINCOLN-MERCURY: 1989-90 GRAND MARQUIS, TOWN CAR
This TSB article is being republished in its entirety to add additional corrective action if the concern was still present after performing TSB 89-20-4.

ISSUE: A "moaning" noise from the air conditioning compressor may be heard at idle speed in high ambient temperatures +90~ F (+32~ C). The noise may be caused by one or more of the following items:

^ An improperly secured compressor discharge hose

^ An improperly positioned negative battery cable

^ An overcharged A/C system
^ A loose engine front cover
^ A loose A/C compressor
^ Loose mounting bracket bolts
^ Resonance related to the compressor mounting bracket



ACTION: Use the following service procedure to eliminate the A/C compressor moan.


1. See if a plastic tie strip is used to secure the A/C compressor discharge hose to the liquid line. If the tie strap is present, remove it.

2. See if the negative battery cable is routed through the tie strap. If it is, re-position the negative battery cable.

3. Secure the negative battery cable with a new tie strap.

4. See if the compressor moan is still present. If the moan is still present, proceed to Step 5.

5. Check the A/C system refrigerant charge. If the A/C system is overcharged, evacuate and recharge the system. Refer to the appropriate 1990 Shop Manual, Section 36-32 for service details.
CAUTION: OBSERVE ALL SAFETY PRECAUTIONS AND FOLLOW THE PROCEDURES OUTLINED IN THE SHOP MANUAL RELATED TO THE USE OF REFRIGERANTS.

6. See if the compressor moan is present. If the moan is still present, proceed to Step 7.

Figure 1:

7. Tighten the engine front cover mounting bolts. Refer to Figure 1 for the correct torque values.

Figure 2:

Figure 3:

8. Tighten all the other A/C compressor and hardware bracket mounting bolts. Refer to Figures 2 and 3 for the correct torque values.

NOTE: DO NOT OVERTIGHTEN ANY OF THE BOLTS.

9. See if the compressor moan is still present. If still present proceed to Step 10.

10. Replace the following A/C components. Refer to the appropriate model year Shop Manual, Section 36 for service details.
^ Disc & Hub Assembly - A/C Clutch
^ Pulley Assembly - A/C Clutch
^ A/C Clutch Coil Kit
^ A/C Clutch Shim Kit

^ A/C Compressor Assembly
^ Evaporator-to-Compressor Hose
^ Compressor-to-Condenser Tube



OTHER APPLICABLE ARTICLES: None
SUPERSEDES: 89-20-4
WARRANTY STATUS: Eligible Under Basic Warranty Coverage
OPERATION DESCRIPTION TIME
901808A Steps 1 through 4 0.3 Hr.
901808B Step 5 ahd 6 0.7 Hr.
901808C Step 7 and 8 0.4 Hr.
901808D Step 9 and 10 2.3 Hr.
DEALER CODING
BASIC PART NO. CONDITION CODE
2882 56
OASIS CODES: 208000, 702000, 703000, 703100