Infiniti I35 2002-2004 HVAC System Bolt Torque Specifications
Infiniti I35 2002-2004

Infiniti I35 2002-2004 HVAC System Bolt Torque Specifications

Detailed torque specifications for HVAC system bolts in the 2002-2004 Infiniti I35, including fasteners for the compressor, condenser, and evaporator.

Updated

Important Information

Safety guidelines and reference information for proper torque application

Quick Reference Guide
ft-lbs → Nm
× 1.356
ft-lbs → kg-m
× 0.138
Nm → ft-lbs
× 0.738
in-lbs → ft-lbs
× 0.083

Common Torque Patterns

Star Pattern

Used for wheels and other circular bolt patterns

Star Pattern torque pattern diagram showing proper bolt tightening sequence
Cross Pattern

Used for gaskets and cover plates

Cross Pattern torque pattern diagram showing proper bolt tightening sequence
Sequential Pattern

Used for head bolts and other critical components

Sequential Pattern torque pattern diagram showing proper bolt tightening sequence

Common Mistakes to Avoid

Over-tightening

Exceeding the specified torque value can stretch or break fasteners, damage threads, or crack components.

Prevention:

Always use a calibrated torque wrench and follow specifications exactly.

Incorrect Torque Sequence

Tightening bolts in the wrong order can cause uneven pressure distribution and potential leaks or damage.

Prevention:

Follow the manufacturer's specified torque sequence pattern.

Dirty Threads

Dirt, rust, or old thread locker can affect torque readings and proper fastener tension.

Prevention:

Clean and inspect all threads before assembly. Use new thread locker if specified.

Reusing TTY Bolts

Torque-to-yield bolts are designed to stretch and must not be reused.

Prevention:

Always replace TTY bolts with new ones. They are single-use only.

Dry vs. Lubricated

Not accounting for whether torque specs are for dry or lubricated fasteners can lead to incorrect tension.

Prevention:

Check if specs are for dry or lubricated threads. Use specified lubricant when required.

Recommended Tools

Torque Wrench (1/4" Drive)

Range: 2-25 ft-lbs
Small fasteners, delicate components

Torque Wrench (3/8" Drive)

Range: 10-100 ft-lbs
Most common automotive fasteners

Torque Wrench (1/2" Drive)

Range: 30-250 ft-lbs
Large fasteners, wheels

Angle Gauge

Torque-to-yield (TTY) bolts

Torque Wrench Care

  • Calibrate annually or after 5,000 clicks
  • Store at lowest setting
  • Keep clean and lubricated

Search Specifications

Search by component name, bolt size, or description

Torque Calculator

Convert between different torque units

Ac Compressor

The A/C compressor is a critical component of the HVAC system, responsible for compressing refrigerant and maintaining system pressure. Proper torque ensures secure mounting and prevents leaks or vibrations.

1

A/C Compressor Mounting Bolts

M10 x 1.5
Torque Value
32.5 ft-lbs (44 N-m)
Important Notes
Torque value is the midpoint of the provided range. Ensure bolts are tightened in a crisscross pattern for even pressure distribution.

Ac Lines

A/C line fittings connect refrigerant lines to the compressor, condenser, and evaporator. Proper torque ensures leak-free seals and maintains system pressure.

1

A/C Line Fittings

M8 x 1.25
Torque Value
13.5 ft-lbs (18 N-m)
Important Notes
Torque value is the midpoint of the provided range. Use a torque wrench to avoid overtightening, which can damage fittings.

Evaporator Core

The evaporator core is located inside the HVAC housing and is responsible for cooling air before it enters the cabin. Proper torque ensures a secure seal and prevents refrigerant leaks.

1

Evaporator Core Housing Bolts

M6 x 1.0
Torque Value
8.5 ft-lbs (11.5 N-m)
Important Notes
Torque value is the midpoint of the provided range. Tighten bolts in a crisscross pattern to ensure even pressure.

Blower Motor

The blower motor circulates air through the HVAC system. Proper torque ensures secure mounting and prevents vibrations or noise.

1

Blower Motor Mounting Bolts

M6 x 1.0
Torque Value
8.5 ft-lbs (11.5 N-m)
Important Notes
Torque value is the midpoint of the provided range. Ensure the motor is properly aligned before tightening.

Heater Core

The heater core provides warm air to the cabin by circulating engine coolant. Proper torque on inlet/outlet fittings ensures leak-free connections.

1

Heater Core Inlet/Outlet Fittings

M8 x 1.25
Torque Value
13.5 ft-lbs (18 N-m)
Important Notes
Torque value is the midpoint of the provided range. Use a torque wrench to avoid overtightening.

Condenser

The condenser is part of the A/C system and is typically mounted in front of the radiator. Proper torque ensures secure mounting and prevents damage to refrigerant lines.

1

Condenser Mounting Bolts

M8 x 1.25
Torque Value
16 ft-lbs (22 N-m)
Important Notes
Torque value is the midpoint of the provided range. Tighten bolts in a crisscross pattern for even pressure.

Hvac Controls

The HVAC control panel houses the controls for the heating, ventilation, and air conditioning system. Proper torque ensures secure mounting without damaging the dashboard or components.

1

HVAC Control Panel Mounting Screws

M4 x 0.7
Torque Value
0.95 ft-lbs (1.3 N-m)
Important Notes
Torque value is the midpoint of the provided range. Use a torque screwdriver to avoid overtightening.

Troubleshooting Guide

Common issues, diagnostic steps, and prevention guidelines

Common Issues

Bolt stretching, stripped threads, uneven torque patterns

Loose Components

Symptoms:
  • Rattling or vibration noises
  • Visible movement in components
  • Uneven panel gaps
Solutions:
  • Clean threads and mounting surfaces
  • Replace damaged fasteners
  • Apply proper torque in sequence
  • Use thread locker if specified

Stripped Fasteners

Symptoms:
  • Unable to achieve proper torque
  • Fastener spins freely
  • Visible thread damage
Solutions:
  • Use thread repair kit if appropriate
  • Install thread insert (HeliCoil)
  • Replace component if threaded hole is damaged
  • Upgrade to higher grade fastener if recommended

Overtightened Components

Symptoms:
  • Cracked or deformed parts
  • Broken fasteners
  • Compressed gaskets or seals
Solutions:
  • Replace damaged components
  • Use new fasteners
  • Follow proper torque sequence
  • Verify correct torque specifications

Diagnostic Steps

Visual inspection, torque verification, thread assessment

1

Visual Inspection

Inspect the affected area for any visible signs of damage or wear

  • Check for cracks or deformation
  • Look for signs of excessive wear
  • Verify proper fastener installation
2

Torque Verification

Verify the torque applied to the fasteners

  • Check the torque wrench calibration
  • Verify the torque specification
  • Compare the applied torque to the specification
3

Thread Assessment

Assess the condition of the threads

  • Check for signs of thread damage
  • Verify the thread type and size
  • Check for proper thread engagement

Prevention Guidelines

Best practices, maintenance tips, tool care

Best Practices

  • Always follow the recommended torque specification
  • Use the correct type and size of fasteners
  • Verify the torque wrench calibration regularly

Maintenance Tips

  • Regularly inspect the affected area for signs of wear or damage
  • Replace damaged or worn-out components promptly
  • Keep the work area clean and organized

Tool Care

  • Regularly clean and maintain the torque wrench
  • Store the torque wrench in a dry and secure location
  • Verify the torque wrench calibration before each use

Frequently Asked Questions

Find answers to common questions about torque specifications

Q1

What is the recommended torque specification for HVAC system bolts in a 2002-2004 Infiniti I35?

The recommended torque specification for HVAC system bolts in a 2002-2004 Infiniti I35 typically ranges between 7-12 ft-lbs (9-16 Nm), depending on the specific bolt and component. Always refer to the vehicle's service manual for exact specifications, as over-tightening can damage components or cause leaks.

Q2

How often should I check the torque on HVAC system bolts?

It is recommended to check the torque on HVAC system bolts during routine maintenance or after any repair work involving the HVAC system. For example, if you replace the compressor or evaporator, recheck the torque after 500 miles to ensure bolts have not loosened due to vibration or thermal cycling.

Q3

Can I reuse HVAC system bolts, or should they be replaced?

HVAC system bolts can generally be reused if they are in good condition and not stripped or corroded. However, if the bolts show signs of wear or were exposed to extreme temperatures, it is advisable to replace them to ensure proper torque and sealing.

Environmental Considerations

Temperature, humidity, and seasonal effects on torque specifications

Temperature Effects

Includes: High Heat, Cold Weather, Thermal Cycling

Temperature can significantly impact torque values and fastener behavior

Cold Weather

Effects:
  • Increased material brittleness
  • Higher torque required due to thread contraction
  • Reduced thread lubricant effectiveness
Recommendations:
  • Allow components to warm to room temperature when possible
  • Consider using winter-grade thread lubricants
  • Check torque values more frequently during winter months

Hot Weather

Effects:
  • Thermal expansion of components
  • Decreased friction in threads
  • Accelerated lubricant breakdown
Recommendations:
  • Check torque when components are at normal operating temperature
  • Use temperature-resistant thread lockers
  • Consider re-torquing after heat cycles

Humidity and Corrosion

Covers: Rust Prevention, Salt Exposure, Moisture Control

Moisture and corrosion can affect fastener integrity and torque values

High Humidity

Effects:
  • Accelerated corrosion formation
  • Reduced friction coefficient
  • Potential thread seizing
Prevention:
  • Use corrosion-resistant fasteners
  • Apply appropriate anti-seize compounds
  • Maintain proper protective coatings

Salt Exposure

Effects:
  • Rapid corrosion development
  • Thread damage
  • Seized fasteners
Prevention:
  • Regular underbody washing
  • Use of sacrificial anodes where appropriate
  • Application of protective coatings

Seasonal Maintenance

Spring, Summer, Fall, and Winter maintenance schedules

Spring

  • Inspect for winter damage
  • Clean and protect exposed fasteners
  • Check torque on critical components

Summer

  • Monitor heat-affected components
  • Check expansion-related loosening
  • Inspect cooling system mounts

Fall

  • Prepare for winter conditions
  • Apply corrosion protection
  • Verify all fasteners are properly torqued

Winter

  • More frequent inspection of critical fasteners
  • Check for salt damage
  • Monitor suspension component torque

Related Resources

Tools, service procedures, and technical bulletins

Recommended Tools

Torque Wrench

Precision torque wrench for accurate bolt tightening

  • Adjustable torque settings
  • Digital torque display
Learn more

HVAC Bolt Socket Set

Socket set specifically designed for HVAC bolts

  • Multiple socket sizes
  • Durable construction
Learn more
Service Procedures

HVAC Bolt Torque Application

Detailed steps for applying correct torque to HVAC bolts

  • Identify the HVAC bolt locations
  • Set the torque wrench to the specified torque value
View full procedure

HVAC System Inspection

Procedure for inspecting the HVAC system after torque application

  • Check for any leaks or loose bolts
  • Verify system operation
View full procedure
Technical Service Bulletins

HVAC Bolt Torque Specifications Update

2003-06-15

Updated torque specifications for HVAC bolts in 2002-2004 Infiniti I35

2002-2004 Infiniti I35

Resolution: Apply updated torque settings using recommended tools

HVAC System Bolt Failure Report

2004-02-20

Report on HVAC bolt failures due to incorrect torque application

2002-2004 Infiniti I35

Resolution: Follow updated service procedures and use precise torque tools

About the Author

Expert automotive knowledge and experience

Alan Montanye - Automotive Technical Specialist
ASE

Alan Montanye

Automotive Technical Specialist

ASE Master Certified Technician with over a decade of hands-on experience in automotive repair and diagnostics.

Facebook Contact
15+ Years
Experience
500+ Guides
Guides
50+ Makes
Vehicles
1000+ Solutions
Solutions

Diagnostic

Specialized in advanced diagnostic techniques using modern scan tools and oscilloscopes.

Repair

Expert in both traditional mechanical repairs and modern vehicle systems.

Additional Expertise

Documentation

Created over 500 detailed repair guides and technical documents.

Training

Conducted technical training sessions and contributed to repair databases.

Certifications & Research

Certifications

  • ASE Master Technician Certification
  • Advanced Diagnostic Specialist
  • Hybrid/Electric Vehicle Systems
  • Performance Tuning Expert

Research & Community

Actively researches emerging technologies and contributes to automotive forums.

Legal Disclaimer

Important information about using this content

Always refer to your vehicle's service manual and take appropriate safety precautions when performing any maintenance or repairs.

General Information
The information provided on this website is for general informational purposes only. While we strive to maintain accuracy in our content, all specifications, procedures, and technical information should be verified against your vehicle's official service manual or with the manufacturer directly.
Warranty & Liability

The content on this website is provided "as is" without any representations or warranties, express or implied. We make no representations or warranties regarding the accuracy, completeness, or availability of the information.

We shall not be liable for any direct, indirect, special, or consequential damages arising from the use of information on this website.

Technical Information
  • All specifications, including torque values, fluid capacities, and maintenance procedures, should be verified against your vehicle's factory service manual.
  • Vehicle specifications and procedures may vary by model year, trim level, and region.
  • Always follow the manufacturer's recommended procedures and safety precautions.
  • Working on vehicles can be dangerous. Always take proper safety precautions and use appropriate safety equipment.
  • If you're unsure about any procedure, consult a qualified professional mechanic.
Intellectual Property
All content, including text, images, and specifications, is protected by copyright and other intellectual property laws. Any unauthorized use or reproduction is prohibited.

© 2025 Infiniti Specs. All rights reserved.

Privacy Policy Terms of Service