Automotive Air Conditioning Information Forum

Hi, first post here. I have a 2018 Nissan Versa that I bought new, has 72,000 miles. The compressor clutch has always made a sound when it is energized, but recently this sound has gotten louder. The noise has not changed in it's nature, only it is louder. It doesn't happen every time, but it happens always when first used in the morning. What could this be? Is it a problem, or is this sound normal? I think the air gap between the drive plate and driven plate might have grown larger, sounds like. Is there an adjustment? Thanks!

Other problems could be in play here, but yes, the clutch air gap might have become larger since the car was new. The largest the air gap would be is when the engine is cold, or in the morning on first start-up. It's not large enough to where the clutch will no longer engage, but it is to the point to where you notice increased noise on engagement.

Can you get a feeler gauge in there to measure it?

The gap, which should be approximately 0.020" (varies by vehicle make), can be adjusted by removing the front of the clutch (you won't have to recover the system to do this if you can get at the front of the compressor in situ), and then removing one shim. There might be more than one shim. In that case, start with the thinnest one and see whether that makes a difference in the noise level and gap measurement. If so, you've found the problem. If not, then we'll have to delve deeper into the system to determine the cause.

Thank you! I saw a YouTube video showing exactly what you just explained. I think the gap looks normal, maybe 20 thousanths? Can I wait a few months without damaging the clutch? Don't feel like crawling under the car right now, even though the procedure appears to be within my abilities/tool hoard. Can I get shims? Nissan wants $700 for a clutch assembly!

A few additional thoughts...

You should hear a click when the clutch engages and then a running-compressor noise, which should be fairly low in volume and constant whenever the clutch is driving the compressor. If it's much louder than that—like the sound a steel-wheel roller skate would make whose bearings have run out of grease—then it's possible that the noise is emanating from the clutch bearing, the idler pulley bearing, or something inside the compressor.

Does it make the noise only when the compressor is engaged, and is it constant or intermittent? It's difficult to do, but can you describe (or better yet, record and post) the sound...whirring, grinding, etc.? Also, has the system ever been serviced, and does it still cool well?

It's hard to say whether the system will continue to run and cool for a few more months depending on what it is.

If it comes down to it, you can get a brand-new compressor/clutch assembly from this site's sponsor, ACKits.com, probably for a lot less than the $700 the dealer asks only for the clutch.

Agree 100%

I've also noticed a similar noise sometimes - only on first compressor engagement of the day - on my 2004 Nissan Frontier. Other than that it works fine. I haven't tried this so far in 2024 as weather hasn't required AC.

I installed a new compressor, condenser, drier on this in 2018 at about 102K miles after the factory compressor seized.

Seems like you are talking about startup slugging. Hard to diagnose without hearing it first hand.

Liquid refrigerant is sitting in your compressor because it's the coldest component in the system. Sounds like a spray paint can rattle for a few seconds while the pistons are smacking into liquid that doesn't want to exit the discharge valves.

Many OEMs put a clutch pulsing in place at first start of the day, many put nothing. Compressor durability tests include startup slugging tests.