Air Conditioning - Growling/Groaning Noise: Overview

89chrysler18

Models

1990 AC, AS & AY Bodies Equipped with A/C and 3.3L Engine


Subject

Air Conditioning System Noise in the Passenger Compartment


Index

HEATING AND AIR CONDITIONING


Date December 11, 1989


No.

24-08-89

(C24-08-9)

P-4256
BODY CODE LEGEND

AC - DYNASTY/NEW YORKER LANDAU/SALON AS - CARAVAN/VOYAGER/CARAVAN C/V/ GRAND CARAVAN/GRAND VOYAGER/TOWN & COUNTRY AY - NEW YORKER FIFTH AVENUE/IMPERIAL


SYMPTOM/CONDITION

Growling or moaning noise in passenger compartment with air conditioning on, worse in high ambient temperatures and/or humidity.

DIAGNOSIS

PROCEDURE TO CHECK FOR COMPRESSOR INDUCED NOISES.

1. Check along the entire length of the discharge, suction and liquid lines for grounding. These lines should not be touching any sheet metal or any other underhood components. Also, check these lines for grounding upon engine roll. Pay particular attention to the following areas: radiator support, shock tower, and bulkhead. If necessary, carefully reroute lines to clear.

2. Check for proper foam rubber insulation at all plumbing line brackets. There should be no contact between the lines and brackets.

CHECK FOR ENGINE MOUNT CLEARANCE.

Check the right (passenger side) engine mount for yoke bracket to insulator assembly clearance. If contact exists between the yoke bracket and insulator assembly, readjustment of front engine mount is necessary.
Procedure to readjust front engine mount:

A. Loosen front insulator assembly fasteners from front cross member.

B. Adjust clearance between front insulator assembly and front engine bracket to 12 mm on passenger side and 7 mm on driver's side.

C. Tighten the front insulator assembly fasteners (30-50 ft.lbs.).


PARTS REQUIRED

Parts must be ordered separately as required.

All AS-Body Vehicles

1 Weight Assembly PN 4384991

AC & AY Body Vehicles as Required

1 Strut Bracket PN 4612008
1 Stud PN 6501589
1 Nut & Washer Assembly PN 6101445
1 Weight Assembly PN 4384991


REPAIR PROCEDURE

NOTE: VEHICLES BUILT BEFORE MDH 1001XX, WILL NEED TO HAVE THE A/C COMPRESSOR MOUNTING BRACKET MODIFIED TO REDUCE THE AMOUNT OF NOISE TRANSMITTED INTO THE PASSENGER COMPARTMENT. VEHICLES BUILT AFTER OCTOBER 1, 1989, HAVE A MODIFIED BRACKET. THIS FACTORY MODIFIED BRACKET WILL NOT ALLOW A BOLT TO BE INSTALLED THROUGH THE HOLE.

Figure 1:

Instructions for Modifying the A/C Compressor Mounting Bracket

NOTE: TO REMOVE THE COMPRESSOR MOUNTING BRACKET ON THE "AS" BODY, IT WILL BE NECESSARY TO DISCHARGE SYSTEM. ON THE "AC" & "AY" BODIES, THE COMPRESSOR CAN BE REMOVED AND SUPPORTED OUT OF THE WAY WITHOUT DISCHARGING.

1. Remove A/C compressor as outlined in service manual.

2. Remove A/C compressor mounting bracket from vehicle.

3. Using a metal cutting saw, remove the section of bracket as shown in Figure 1.
NOTE: THERE MUST BE NO CONTACT BETWEEN THE MOUNTING BRACKET AND ENGINE BOSS IN THE MODIFIED AREA.

4. Install compressor mounting bracket and torque mounting bolts to specifications provided in service manual.

5. Install compressor assembly and torque mounting bolts to specifications in service manual.

NOTE: ON 1990 AC & AY BODY VEHICLES BUILT BEFORE MDH 0824XX, IT WILL BE NECESSARY TO INSTALL AN A/C COMPRESSOR STRUT BRACKET PN 4612008. VEHICLES BUILT AFTER AUGUST 24, 1989 ALREADY HAVE THIS STRUT INSTALLED.