Flapping drive belt

[Mr. Towed]

When my AC compressor cycles on the drive belt flaps wildly between the tensioner and the compressor. When the AC compressor cycles off it stops flapping. Has anyone noticed this before? It looked like the AC clutch was out of balance because it looked that way when it was spinning so I had my mechanic replace the compressor. Since the belt still flaps when the compressor is running the next step would be to replace the tensioner though it looks good and feels tight. Does this sound like the right direction?

The new compressor, a Denso, has an odd way of cycling off. It would stop for a millisecond then start spinning again for about a second then cycle off. The original compressor didn't do that and I don't recall ever seen that behavior before so I'm thinking put the old compressor back on and return the Denso.

2006 Liberty 3.7 143k miles

 

[tjkj2002]

Replace both the tensioner and belt.

 

[tommudd]

Replace both the tensioner and belt.

VERY soon

 

[libordemise]

Ya I learned to always change the tensioner at the same time as the belt, embarrassing noises...

Sent from my LG-K210 using Tapatalk

 

[dougmac]

When my AC compressor cycles on the drive belt flaps wildly between the tensioner and the compressor. When the AC compressor cycles off it stops flapping. Has anyone noticed this before? It looked like the AC clutch was out of balance because it looked that way when it was spinning so I had my mechanic replace the compressor. Since the belt still flaps when the compressor is running the next step would be to replace the tensioner though it looks good and feels tight. Does this sound like the right direction?

The new compressor, a Denso, has an odd way of cycling off. It would stop for a millisecond then start spinning again for about a second then cycle off. The original compressor didn't do that and I don't recall ever seen that behavior before so I'm thinking put the old compressor back on and return the Denso.

2006 Liberty 3.7 143k miles

The belt thing... I changed the tensioner assembly on mine earlier this week for that problem. Mine was pretty noisy. That fixed it.

Have you put gauges on it to see what the discharge and suction pressures are? That would be a good place to start if you have the clutch cycling abnormally.

 

[ltd02]

I changed my belt and tensioner a couple weeks back and didn't even know it was bad. It was the original belt so I figured what they heck, 12 years was long enough. Made a huge difference. Much more quiet and the bouncing belt is gone. The OE tensioner has a "gauge" built into it. If it is beyond a certain distance (24mm) the belt is stretched and bad tension will result. The Gates replacement doesn't have the marks in the housing.

 

[Mr. Towed]

My son replaced the tensioner and belt and that fixed the flapping. The issue with the AC compressor turned out to be a bad Schrader valve on the low side I think. It was the larger valve that was leaking. He replaced that and charged the system and it is now cycling on and off properly. Thanks for the help.