Replace serpentine belt?

I have a different tensioner there isnt a spot for that cant upload pic

2004 Chrysler Town and Country 3.8 L V6.

The belt flaps between the air conditioner compressor and the crank pulley. It makes no difference if the AC compressor is enguaged or not.

It seems to be a function of the idle speed of the engine It flaps at 750 rpm =/- 150. At 600 or 900 it will not flap.

I have replaced the water pump, the alternator, serpentine belt last fall. The problem seemed to be fixed until now.

We have had a cool temperatures for the last few days and the belt flap is almost not existent. I noticed that during the cool weather that the idle RPM is at 600. As the temperature increase to the mid 90's the engine idles at 750 and the belt flap is back.

I have tried a second belt and a replacement belt tightner and found that the flap was more severe with the new Gates tightner.

The flap is independent of whether or not the air conditioner compressor is engaged.

All of the pulley are in-line and no visible wobble even when the belt is flapping.

My parts dealer indicates that he sells quite a few harmonic balancer drive pulleys. Could I have a deteriation of the rummer which is molded into the pulley?

Thanks for your help.

Jim

Yes the belt in on correctly. I had the flap problem last August and at that time I replaced the water pump, altenator and belt and the problem went away till Feburary of this year. I was on my way to Florida. It flaped for a day or so and then went away.
It returned late June this year. Replaced the belt still flaped. Replaced the tightner and it still flaped. With the transmision in park the belt doesn't flap. You turn on the AC on or off and no flap. Put the transmission in drive and the belt begins to flap. While in drive the belt will STOP flapping when the engine RPM slows down to about 600. Increase the RPM and the belt will flap between 650 to 850 RPM. 750 being the point where flap is the worse. With some one else holding the brake down I can observe about 1/2 inch of flap between the harmonic balancer pully and the A/C pulley. All of the pullies are running true. The belt tightner pully is moving to take up the belt slack.

With the belt off I have checked the all of the pullies for roughness and bearing problems by turning them. Nothing evident.

I got up yesterday and thougnt I would make a table of what I observed to help the mechanic figure out what to replace next. Started it up and backed it out of the garague. NO flap. Drove it around town and NO flap.

I tried the broom handle trick to listen to the altenator. NO bearing noise. NO AC bearing noise.

The only thing I can say definitly is it will only flap when the transmission is in drive and I stop at a stop light. People start looking around to see where the nose is comming from.

Could this be a transmission problem?

Expensive to have it repaired and it isnt the problem!

Same for the AC

Thanks for your help.

This may be a good problem to stump your mechanic friends with.

In my last note I indicated that the problem went away. That was on the 9th. It's back! On the 21st. I went on a trip and drove about 600 miles and it is back. It returned on the last day. Probably some where around 500 miles into the trip.

To day I purchased some fule injector cleaner to see if I have a miss at idle when the transmission puts load on the engine. Can't hear a miss.

JIM

It only happens when the transmission is in drive or reverse and the car is not moving.

Put it in neutral an the flapping stops. It makes no difference if the AC in on or off.

Jim

I sure wished it had a carborator with an idle adjustment screw.

In neutral, with ac off, idle is 800 NO flap
In neutral, A/C on, idle is 725, NO flap
In drive, A/C on or off idle is 650, belt Flap
In reverse, A/C on or off, Idle is 650, Belt Fap

Put foot on brake and bring RPM up to 900 and flap goes away.

Last week when it stoped flapping for several days the idle RPM was slightly lower then 600.

Jim

Jim

When my van is idling it makes a tweetying like sound it is driving me crazy. We have replaced the serp belt, water pump and power steering. Sometimes I believe it has something to with the air conditioner it is louder when it is on.

I was driving in heavy rain last night. I was almost home when my battery and water light came on. As I was turning into my drive, my power steering went out.
This morning, the warning lights are off but I still don't have power steering.
About 2 years ago I had to replace the serpentine (sp?) Belt after similar warning lights came on. Could it be the same problem? What else do you think it could be?

Thank you for your help!

2000 Chrysler Town and Country

price to change serpentine belt

3.8L V6
Had replaced the casting that is the lower alternator mounting pivot point. Installed a new HD serpentine belt. All alignment seemed good. The tension indicator was at its mark. All functioned well for 3-5 months then the belt removed itself. Checked things and reinstalled the belt. 2-3 weeks later it repeated the removal. Reinstalled it and drove it home. Any suggestions?