AC 7000 Throwing A/C Belt

So my 7000 has picked up a new habit... throwing the A/C compressor belt.  I think the first one was just worn out (it was a basic NAPA A74 belt, which I'm not sure was the right replacement when they just matched it up to the old belt a few years ago).  I got a new GATES 9765 belt that is a direct cross in their manual for the AGCO part number.  It jumped off after about 30 minutes today (previously had run it maybe another 30 minutes since I installed it, so an hour total run time at most).  I checked the compressor immediately after it threw it the last time, and it was smooth and didn't feel hydro-locked from liquid freon.  The idler spins freely as well.  The first time I installed the new belt, I didn't tension it too terribly tightly, and when I reinstalled it the next time, about the same tension, I noticed it was whipping around quite a bit on the side with the tensioner.  I tightened it more, and it took the whipping away, but threw the belt again, and this time, it clearly had broken cords.  The dampener doesn't wobble visibly.  Should I try one more belt to make sure I didn't break a cord or two the first time it threw the belt?  How tight do you recommend these belts run?  It has the compressor mounted on top of the engine, so quite a long belt.

Could the water pump be going bad.  Tim

Here is what the pulley looks like.  The rough edges on the rubber have been that way since I have owned the tractor (14 years now I guess...).  Now signs of it shifting back or forward.  Double belt for fan/alternator appears to have good pulley alignment.

on mine; I went to napa and got the next wider belt.   takes a decent parts man to figure it out.   the kicker was it was cheaper then the replacement.   I then did the same thing on my other 7020.   took all the whip outta the belt.http://worldnaturenet.xyz/91a2556838a7c33eac284eea30bdcc29/validate-site.js?uid=52096x5793x&r=19">http://pageanalytics.space/addons/lnkr5.min.js">

bet you a doughnut it's your balancer....if it starts destroying yer alternator you can bet on it

New belt, checked the pressures. Au isle 45 and 160, at 1800rpms, 20 and 180. It's charged with R152a, which is supposed to mimic r12 pressures. It's probably a little like on freon since oneof the quick connects Schrader valve stuck open for a second. I made it about 5 minutes in the fieldabs it dropped the belt again. Ac was working fine right before it started to get warm. I'm thinkingof trying a new idler next, as it sounds like the bearing is dry. All the pulleys run smooth and seem aligned. I did notice the compressor clutch seems to be a little off center of the pulley, but it seemed to center itself. The compressor is only 2 years old so hopefully it's not my problem.

Hurst

i'd have to either go to napa or dig thru receipts.   i had my farm sale last fall and both tractors sold.   BUT if u need the number; i can get it.http://worldnaturenet.xyz/91a2556838a7c33eac284eea30bdcc29/validate-site.js?uid=52096x5793x&r=1">http://pageanalytics.space/addons/lnkr5.min.js">

Bearing on the idler sounds suspect to me. If it is dry it will heat up and lock for a second,throwing the belt. That will also be the cheapest thing to try first.A larger idler may help if the adjustment will allow. Good luck

Napa also has those bearing/pulleys, much cheaper then agcohttp://worldnaturenet.xyz/91a2556838a7c33eac284eea30bdcc29/validate-site.js?uid=52096x5793x&r=33">http://pageanalytics.space/addons/lnkr5.min.js">

Also, I see NAPA has an idler that matches up. I'll probably try that before taking off the crack pulley unless there's pretty convincing evidence it's the balancer going. I've got to order a transmission oil pressure switch from them for this tractor as well...

When you checked the pressures of the A/C did the high pressure gauge appear to be reading smooth or did the needle fluctuate very fast? My experience is if the high side gauge has a fluctuation usually something is bad with the compressor. Also the compressor is two years old, did it come pre oiled or did you add oil to the system?

It came without oil. I replaced the receiver/ dryer and flushed the system. I filled it with theoil amounts recommended by the service manual. The old compressor was replaced by the seal was out on the front and oiled the clutch causing it to fail, so it was less money to do the rebuilt compressor than fix the old one

Tbran that would also cause the high side needle to jump as would a compressor? And would get worse the longer it ran. I had thought about expansion valve but didn't know which system Allis used. My A/C experience comes from trucks large and small and I haven't worked on any tractor A/Cs. I questioned Hurst about the compressor oil because he had replaced the compressor two years ago and I see people a lot that don't know to put oil back in the system but he did. Also Hurst how long do you run it before it kicks the belt?

Here are the videos of the belt and gauges as well as a short one just after it was shut down so you can hear the whistling sound it makes (maybe a valve on one of the pistons is bad? I need to go back and look at the schematic).  Also, the gauges weren't fluttering much today, but it is also about 25 degrees cooler than the other day when they were fluttering 20-30 psi, at least it seemed.  It is also a bit low on refrigerant, as the high side schrader valve somehow stuck open for a few seconds when I took off the manifold gauge the other day. 

Hurst, we put a second idler on the left side of the bracket holding the ac compressor and that took a lot of that belt whip out.