AC Hose Assembly

Complete replacement of the AC hose assembly on a 2017 Maserati Levante 3.0L V6 Twin Turbo, including refrigerant recovery, hose removal/installation, and system recharge.

Warnings

Tools required

Parts

• AC hose assembly (specific to position being replaced) × 1 — Use OEM specification
• AC line O-ring set × 1 — Use OEM specification
• R134a refrigerant × 1 — Approximately 1.3 lbs per system spec
• PAG 46 compressor oil × 1 — 50ml
• UV dye (if not pre-charged) × 1 — Use AC system compatible dye

Preparation

1. Park vehicle on level surface and engage parking brake
2. Allow engine to cool completely if recently operated
3. Verify AC system operating pressures before beginning work (low side should be 25-45 psi at idle, high side 150-250 psi)
4. Identify which specific AC hose assembly requires replacement (suction, discharge, or liquid line)
5. Place fender covers to protect paint from refrigerant oil
6. Ensure recovery machine is properly calibrated and has adequate tank capacity

Procedure

1. 1

   Recover refrigerant from AC system
   Connect AC recovery machine to service ports on low and high pressure sides. Follow machine manufacturer procedure to completely recover all refrigerant from the system. Verify system pressure is at 0 psi and remains stable for 5 minutes to confirm complete recovery. Record amount of refrigerant and oil recovered for recharge reference.
2. 2

   Access AC hose assembly
   Remove engine cover by lifting at rear and pulling forward to release clips. For rear wheel drive Levante, access to condenser and evaporator lines is from the engine bay front area. Remove air intake duct and battery cover if accessing passenger side lines. The compressor discharge and suction lines are located on driver side of engine bay.
3. 3

   Remove mounting brackets and clips
   Identify and remove any mounting brackets securing the AC hose assembly to body or engine. Remove plastic clips and any wire harness retainers that secure the hose routing. Take photos of hose routing for reinstallation reference. Note the position of any insulation sleeves or heat shields.
   Torque spec

   Mounting Bracket Bolts26 Nm (19 lb-ft)
4. 4

   Disconnect AC line fittings at compressor
   Using appropriate flare nut wrenches, carefully loosen the AC line fittings at the compressor connections. Support the compressor body while loosening to prevent stress on mounting bolts. Once fittings are loose, carefully separate lines and immediately cap all open ports with plugs to prevent contamination and moisture entry.
   ⚠Use flare nut wrenches to prevent rounding off fitting nuts. Standard open-end wrenches will damage the soft aluminum fittings.
   Torque spec

   AC Line Fittings20 Nm (15 lb-ft)
5. 5

   Disconnect remote end of hose assembly
   Locate the opposite end connection point (condenser, evaporator, or expansion valve depending on which hose is being replaced). Use flare nut wrenches to disconnect the fitting. For evaporator connections inside the cabin, access may require removal of glove box or lower dash panels. Cap all openings immediately.
   Torque spec

   AC Line Fittings20 Nm (15 lb-ft)
6. 6

   Remove old AC hose assembly
   Carefully route the old hose assembly out of the engine bay, noting the exact path it followed through brackets and around other components. Check for any additional mounting points or grommets that need to be transferred to the new hose. Inspect removed hose for cause of failure (abrasion, stone damage, connection leaks).
7. 7

   Prepare new hose assembly
   Remove protective caps from new hose assembly only immediately before installation. Remove old O-rings from all connection fittings using pick tool, being careful not to scratch sealing surfaces. Install new O-rings and apply thin coat of clean PAG 46 oil to all O-rings. Add 30ml of fresh PAG 46 oil into the new hose assembly if replacing the suction line, or 20ml if replacing discharge line.
   ⚠Never reuse old O-rings. Contaminated or improperly lubricated O-rings are the primary cause of AC system leaks.
8. 8

   Install new AC hose assembly
   Route new hose assembly through engine bay following exact path of original. Ensure hose does not contact sharp edges, hot exhaust components, or moving parts. Install any grommets or protective sleeves. Verify adequate clearance for engine movement and vibration.
9. 9

   Connect and torque AC fittings
   Hand-thread AC line fittings to compressor until snug to ensure proper alignment. Using calibrated torque wrench and flare nut crowfoot adapter, torque AC line fittings to specification. Repeat process for remote connection point. Ensure fittings are properly seated before applying torque.
   ⚠Critical torque specification - under-torquing causes leaks, over-torquing damages aluminum threads. Account for crowfoot adapter extension when calculating torque wrench setting.
   Torque spec

   AC Line Fittings20 Nm (15 lb-ft)
10. 10

    Reinstall mounting brackets
    Install all mounting brackets and secure AC hose assembly in original positions. Torque mounting bracket bolts to specification. Ensure hose is properly supported and not subject to stress or vibration. Reinstall any wire harness clips or insulation shields.
    Torque spec

    Mounting Bracket Bolts26 Nm (19 lb-ft)
11. 11

    Evacuate AC system
    Connect vacuum pump to AC service ports. Evacuate system to at least 500 microns and maintain vacuum for minimum 45 minutes. System should hold vacuum without decay, indicating no leaks. If vacuum rises above 1000 microns, there is a leak that must be repaired before proceeding.
    ℹ️Proper evacuation removes all moisture from the system. Moisture causes corrosion, acid formation, and compressor failure.
12. 12

    Recharge AC system
    Using AC manifold gauges or charging station, recharge system with R134a refrigerant to specification (approximately 1.3 lbs or 590 grams for Levante 3.0L). Charge through low-side port only with engine running and AC on maximum. Add refrigerant slowly to avoid liquid slugging the compressor. If oil was not pre-added to hose, inject appropriate amount through service port.
13. 13

    Leak test system
    With system fully charged, use electronic leak detector or UV light (if dye was added) to check all connection points for leaks. Inspect compressor shaft seal, all fittings, and along hose assembly length. Verify static pressure holds for 15 minutes with engine off.

Reassembly

1. Reinstall air intake duct and battery cover if removed
2. Reinstall engine cover ensuring all clips engage properly
3. Clean any spilled PAG oil from painted surfaces immediately as it damages clear coat
4. Document refrigerant charge amount and date for service records

Verification

• Start engine and set AC to maximum cold with high blower speed
• Verify compressor clutch engages and cycles normally
• Check low side pressure stabilizes at 25-45 psi and high side at 150-250 psi at idle with ambient temperature 70-80°F
• Verify center vent temperature reaches 38-42°F within 5 minutes of operation
• Inspect all connection points for refrigerant oil seepage indicating leaks
• Listen for unusual compressor noises indicating contamination or insufficient oil
• Test AC performance during road test under various engine loads

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