Farm Equipment - 7020 air conditioning belt

Print Page | Close Window

7020 air conditioning belt

Printed From: Unofficial Allis
Category: Allis Chalmers
Forum Name: Farm Equipment
Forum Description: everything about Allis-Chalmers farm equipment
URL: https://www.allischalmers.com/forum/forum_posts.asp?TID=124677
Printed Date: 18 Jun 2025 at 12:48am
Software Version: Web Wiz Forums 11.10 - http://www.webwizforums.com

Topic: 7020 air conditioning belt

Posted By: tomNE
Subject: 7020 air conditioning belt
Date Posted: 16 Jun 2016 at 7:05pm

I've been having problem with the belt about every year. they wear the sides out and they squeal when the compressor kicks on, usually the second time. the second time there is more head pressure. I went to NAPA and asked for a heavy duty belt. none available. I then told them my problem. they then went into the belt book and ordered a belt by length and width. I installed it last night, so by the end of the weekend, i should know more. this tractor only has 6000 hours, so i wouldn't think the pulleys should be worn out. Anyone else had this problem?

-------------
AC from the start of my families farming career till the end!

Replies:

Posted By: MACK
Date Posted: 16 Jun 2016 at 10:18pm

How much pressure are you running on hi side? 134A or R12? Has radiator and condenser been washed out lately? MACK

Posted By: tomNE
Date Posted: 16 Jun 2016 at 10:22pm

134a proly 140 on topside, depending on outside temp. i keep the condenser fairly clean.

my problems usually occur if i shut down the tractor to fill the drill or answer a phone call. when i start back up, it's tricky to get compressor going again.

-------------
AC from the start of my families farming career till the end!

Posted By: SHAMELESS
Date Posted: 16 Jun 2016 at 11:45pm

can you try a little belt dressing on it? don't take much

Posted By: DrAllis
Date Posted: 17 Jun 2016 at 6:00am

That belt is very long and needs to be kept tight. I'd prefer to see the shortest belt possible, as the more you slide the idler out to tension the belt, the less degrees of wrap there is on the A/C clutch pulley. A good quality belt stretches less under load. Is there a chance the expansion valve might not bleed off quite as fast as it should, causing a high load upon clutch engagement??

Posted By: tomNE
Date Posted: 17 Jun 2016 at 6:51am

I know just enuff about the interworkings of AC systems to be dangerous. but the expansion valve theory is somethings i will check out. thank you!

-------------
AC from the start of my families farming career till the end!