Replacing the A/C Compressor Clutch on a 1987 Chevrolet V20
If your classic Chevy's air conditioning is blowing warm, a faulty A/C clutch could be the problem.
- For the 1987 V20, a new aftermarket clutch is your main option; OEM parts are largely unavailable.
- Symptoms of failure include grinding noises, intermittent cooling, and no 'click' when turning on the A/C.
- Replacing only the clutch is cheaper and avoids opening the A/C system, but requires a special puller/installer tool.
- Driving with a seizing clutch bearing is risky; it can break the drive belt and strand you.
Is Your V20's A/C Blowing Warm Air?
When the air conditioning in your 1987 Chevrolet V20 stops blowing cold, a bad A/C compressor clutch is a common culprit. This component is responsible for engaging the A/C compressor. If it fails, the compressor can't do its job, leaving you with warm air on a hot day. Before assuming the entire expensive compressor unit has failed, it's worth investigating the clutch itself.
Symptoms of a Failing A/C Clutch
A failing A/C clutch on your V20 will show several warning signs. Being able to spot them can help you diagnose the problem correctly.
- Loud Noises: A grinding or high-pitched squealing sound from the engine bay when the A/C is turned on is a classic sign of a bad clutch bearing. The noise may stop when you turn the A/C off.
- No "Click" Sound: When you switch on your A/C, you should hear an audible "click" as the clutch's electromagnet engages. If you don't hear this sound, the clutch may not be receiving power or the internal coil may have failed.
- Intermittent Cooling: If the A/C blows cold, then warm, then cold again, the clutch could be failing to maintain a solid engagement. This can be caused by a worn-out clutch surface or an incorrect air gap between the clutch plate and the pulley.
- Clutch Won't Engage: You can visually inspect the clutch. With the engine running and A/C on, the center plate of the clutch should be spinning along with the outer pulley. If the pulley is spinning but the center plate is stationary, the clutch is not engaging.
- Visible Damage or Debris: Look for black dust (from a worn clutch) or signs of burning around the compressor. In severe cases, the clutch can physically come apart.
Check Refrigerant Levels First
Low refrigerant levels will prevent the A/C system's low-pressure switch from allowing the clutch to engage. This is a safety feature to protect the compressor. Before replacing the clutch, it's wise to ensure your system is properly charged, as this can mimic the symptoms of a failed clutch.
Choosing the Right Aftermarket Clutch
For a 1987 Chevrolet V20, finding a new Original Equipment Manufacturer (OEM) clutch from GM is highly unlikely. The market is now dominated by new aftermarket parts. Brands like Four Seasons are widely available for your truck.
When it comes to aftermarket parts for a vintage vehicle, quality can vary. Some reviews for Four Seasons compressors and clutches are positive, citing good fit and quiet operation. However, other users report issues like premature failure or noisy operation. Given that aftermarket is the most practical choice, it's important to buy from a supplier with a good warranty and return policy.
Replace Just the Clutch or the Whole Compressor?
If only the clutch has failed (e.g., a bad bearing or coil), you can replace just the clutch assembly. This is more affordable and, crucially, does not require opening the sealed refrigerant system, which saves you the cost of evacuating and recharging the A/C. However, if the compressor itself is leaking, making internal noises, or has seized, you must replace the entire compressor and clutch unit.
Known Issues for the 1987 Chevrolet V20
Searches for specific recalls or Technical Service Bulletins (TSBs) from Chevrolet for the A/C compressor clutch on the 1987 V20 did not yield any specific results. This is common for vehicles of this age. Most issues are related to general wear and tear of components over several decades. The most common problems are bearing failure and coil burnout, which are typical for any A/C clutch of this era.
| Part | Estimated Cost |
|---|---|
| New Aftermarket A/C Clutch Kit | $153 - $182 |
| Shop Labor | $150 - $250 |
| Total Estimated Cost | $303 - $432 |
Frequently Asked Questions
Can I replace the A/C clutch myself?
Yes, if you are mechanically inclined. The process does not require opening the refrigerant lines. However, you will likely need a special A/C clutch puller and installer tool kit, which can often be rented from auto parts stores. The most critical part of the installation is setting the correct "air gap" between the clutch plate and pulley.
What is the A/C clutch "air gap"?
The air gap is the specific, small space between the clutch plate and the pulley when the A/C is off. This gap must be set to the manufacturer's specification using small spacers called shims. If the gap is too large, the electromagnet won't be strong enough to engage the clutch. If it's too small, the clutch may drag when it's supposed to be off.
Why did my A/C clutch fail?
Failure is usually due to age and wear. The most common points of failure are the pulley bearing, which wears out from constant spinning, and the electromagnetic coil, which can burn out or develop an internal short over time. Sometimes, a slipping clutch can overheat and cause damage to the clutch surfaces.
Is it safe to drive with a bad A/C clutch?
You can drive the truck, but it comes with a risk. If the clutch bearing is failing and seizes completely, it can cause the serpentine belt to break. This would not only disable your A/C but could also stop other critical components like the water pump and alternator, leaving you stranded. It's best to not use the A/C or defroster and get it repaired soon.
Technical Specifications
OEM Part Numbers: 88964868
Cross-reference part numbers for the entire compressor assembly include Four Seasons part numbers 57230, 57235, 58230, and 58235. The compressor uses a 1-groove pulley. Always verify the specific compressor model (e.g., R4) on your truck before ordering parts.
We Have This Part in Stock
The information in this article is provided for general reference and educational purposes only. Vehicle specifications, procedures, and part compatibility can vary by production date, trim level, and region. Always consult your vehicle's factory service manual and verify part numbers before purchasing or performing repairs. Safety-critical components such as airbags, seat belts, and braking systems should be installed by a qualified professional.
- Chevrolet V20: