Automotive Air Conditioning Information Forum (Archives)

Provided by www.ACkits.com

We've updated our forums!
Click here to visit the new forum

Archive Home

Search Auto AC Forum Archives

Keeps breaking the belt Pages: 12Last

mhfd112 on Mon September 17, 2007 8:00 AM User is offline

Year: 2003
Make: Chevy
Model: hd 1500

I helped a friend replace his compressor on his truck. All parts came from Ackits. Since the repair the idler for the ac belt jumps all over the place. It either throws or breaks the belt. My buddy has put on a new idler pulley. Still no good.

Does anyone have any suggestions?

Thanks

Chick on Mon September 17, 2007 8:06 AM User is offlineView users profile

What are the pressures? Are the pullies lined up correctly, give us as much information as possible, like whyt did you change the compressor, what was done before changing it, like flush, parts changed etc... Did it do it before the compressor change?

-------------------------
Chick
Email: Chick

---------------------------------------------

Freedoms just another word for nothing left to lose

mhfd112 on Mon September 17, 2007 9:22 AM User is offline

The compressor had a leak, but otherwise the system worked good. The problem appeared after the compressor change. I didn't record the pressures when I charged it, but after charging the recommended weight we had a vent temp in the 42 to 45 range. Everything looked fine. The only time I record the numbers is if there looks to be a problem. System wasn't flushed. Orifice tube and accumlator were replaced. O-tube was clean. Ran the vacuum pump on it for about an hour. At lower steady rpms belt idler is fine. At higher rpms and when accelerating the idler begins jumping. No compressor noise noted.

Chick on Mon September 17, 2007 9:30 AM User is offlineView users profile

Get the pressures at idle and 2000 rpm and check that the pullies are all lined up properly. make sure the belt is routed properly and see if it does it with the AC off or just when it's on..

-------------------------
Chick
Email: Chick

---------------------------------------------

Freedoms just another word for nothing left to lose

mhfd112 on Mon September 17, 2007 9:37 AM User is offline

Can't take the pressures. My buddies truck is 5 hours away. I just emailed him and asked if it does all the time or only when the ac is on. Belt is routed correctly. This truck has a separate belt for the compressor. It is a short one. Goes around the crank pulley and ac clutch.

TRB on Mon September 17, 2007 10:45 AM User is offlineView users profile

What was your invoice number? Lie to see what was sent out and compare to OEM specs. Is the belt extended all the way out on the idler and still flopping? What brand of belts are being used?

-------------------------

When considering your next auto A/C purchase, please consider the site that supports you: ACkits.com
Contact: ACKits.com

bearing01 on Mon September 17, 2007 10:49 AM User is offline

Are you sure the pullies are lined up? Sounds like one is out of line.

iceman2555 on Mon September 17, 2007 4:19 PM User is offlineView users profile

My vote goes for a bad compressor......one or more reed valves are broken......seen this happen on Surbs and Tahoes....but could also happen on the truck series. Low mount compressors tend to accumulate liquid refrigerant during non operational periods. Start up and a reed valve breaks....and the resultant vibration results in the belt being thrown. If this is indeed the case....the only option is a compressor replacement....and then check with the dealer....there is a re-flash for the computer to allow for compressor clutch operation during start up.....(normal start up by passes the clutch). This reflash is available for the Surbs/Tahoe....but check for the truck also.
Good luck....

-------------------------
The strongest reason for the people to retain the right to keep and bear arms is, as a last resort, to protect themselves against tyranny in government.
Thomas Jefferson

mhfd112 on Mon September 17, 2007 4:45 PM User is offline

Order # was 3498.

Buddy says pulleys are lined up best he can tell laying on his back looking up at it. The original belt that broke was oem. Last two were Duralast from Auto Zone.

He also states there there is noticeable drag on the engine at idle when you turn on the ac. He suspects there is trouble with the compressor.

This is what he wrote when asked if the belt was extended all the way out. "What do you mean all the way out? I went from the lower end of tension on the idler to about 50% or total tension available on it based on the little casting nubs that limit the pulley travel."

He also said he didn't notice any trouble or chatter until about 3 days after we did the job.



TRB on Mon September 17, 2007 5:00 PM User is offlineView users profile

If you think it is a defective compressor we can warranty it out for you. Just let our staff know and we can get things processed for you.

-------------------------

When considering your next auto A/C purchase, please consider the site that supports you: ACkits.com
Contact: ACKits.com

iceman2555 on Mon September 17, 2007 8:15 PM User is offlineView users profile

It is highly doubtful that the compressor is defective...."At lower steady rpms belt idler is fine. At higher rpms and when accelerating the idler begins jumping."
Still think it is a reed valve problem.....causing a 'short duration' lock up of the compressor. Although, wonder if it could be a 'high side' (discharge) pressure problem...a build up of discharge pressure due to a possible restriction in the condenser. Although, think this would be indicated by a clutch that may display over heating conditions....not locking and unlocking.
With the engine at idle...doors open..max cool...high blower.....a temp drop test across the condenser would be a good starting point. If excessive...this could be the culprit...but still first thoughts are for the liquid flooding/reed valve problem.

-------------------------
The strongest reason for the people to retain the right to keep and bear arms is, as a last resort, to protect themselves against tyranny in government.
Thomas Jefferson

mhfd112 on Mon September 17, 2007 9:25 PM User is offline

Iceman,

I don't quite follow you. You think the compressor was good, but now has a broken reed valve? What causes the broken reed valve? It sounds like you are suggesting a problem in the computer?

Keep in mind this system was working fine as long as it had freon in it. It was charged early in the summer and dye was added at a dealer. About a month down the road no more cooling. It went back to the dealer. They said dye indicated a big leak at the rear of the compressor.

Chick on Mon September 17, 2007 9:36 PM User is offlineView users profile

"Keep in mind this system was working fine as long as it had freon in it. It was charged early in the summer and dye was added at a dealer. About a month down the road no more cooling. It went back to the dealer. They said dye indicated a big leak at the rear of the compressor. "
------------------------------------------------------------------------------------------------------------------------------

Is this the new compressor, or the original failure?? hard to sort it out..

-------------------------
Chick
Email: Chick

---------------------------------------------

Freedoms just another word for nothing left to lose

TRB on Mon September 17, 2007 9:44 PM User is offlineView users profile

I would like to know what the pressures are!!! Sending out replacement parts is not an issue if they are defective. But hate to send them out only to have the same condition again.

Chick the compressor we sent was a new model.

-------------------------

When considering your next auto A/C purchase, please consider the site that supports you: ACkits.com
Contact: ACKits.com

Chick on Mon September 17, 2007 9:58 PM User is offlineView users profile

Tim, I'm asking if the description he just gave was with the new compressor, or the old one which was the reason for changing it...Yes., pressures are needed as I said in my first post..Would tell us a lot, but I guess being 5 hours away, it may take some time...

-------------------------
Chick
Email: Chick

---------------------------------------------

Freedoms just another word for nothing left to lose

Dougflas on Mon September 17, 2007 11:22 PM User is offline

I feel Iceman has it pegged. GM had mounted compressors down low causing liquid migration. Common problem.

mhfd112 on Tue September 18, 2007 6:12 AM User is offline

I will see if I can get him to have the pressures checked or better yet pick up a set of gauges so he can check it himself.

NickD on Tue September 18, 2007 8:14 AM User is offline

With two GM vehicles with the compressors mounted on the ground, or close to it, should I expect liquid migration to seize the compressors also? Hope not, one managed to survive 15 years and the other, four years now.

Poster states that the system wasn't flushed, new accumulator, good idea there, but nothing mentioned about the type or quantity of the oil. Feel flushing is always in order and the correct amount and type of oil should be added. Possible the new compressor is the problem, but there are some if's in this area. Anyone hand turn the hub yet?

mhfd112 on Tue September 18, 2007 11:15 AM User is offline

Nick,

I used dec pag from Ackits. I used the viscosity that they said to use, think it was 46. Two ounces in the accumulator.

I will tell my buddy to turn the compressor by hand and report back what he finds.

NickD on Wed September 19, 2007 6:55 AM User is offline

This leads to more questions, was the vehicle originally equipped with DEC oil, or do you have a mix now? Did just adding two ounces bring the oil level to the recommended value?

If not, feel you know what the problem is.

mhfd112 on Wed September 19, 2007 9:20 AM User is offline

Nick,

I don't know if came with dec pag 46 or not. Of course I know the only way to get the exact amount of oil is to flush and refill, however information that I have read on this board indicates that it is acceptable to not flush a system that has a leak of this nature as long as the system is clean. The orifice tube on this one was clean.

iceman2555 on Wed September 19, 2007 9:33 AM User is offlineView users profile

PAG 46 is the correct lubricant for this Denso supplied compressor. Although adding only 2 oz to the accumulator may be a bit low....but then the system was not flushed either...so does the two oz hurt....probably not...since most orifice tube system will accommodate this extra amount.
What is questionable...was how much as added to the compressor....or was it installed with the OE amount of lubricant?
The indication that the system operates well below a specific RPM and no compressor noise negates the idea that the lubricant is a problem.....unless it is exceeding excessive (?).....belt throwing and possible breakage at higher RPM does tend to indicate a possible short duration lock and release problem.
Still think it is the reed valves.
And the idea that the system was not flushed.....as appalling as it is to many of us....know that a non scientific survey was conducted last year.....and a vast....very large percentage of 'techs' do not flush a system prior to installation of a new compressor. Boggles the mind.....those that should know the benefits....do not accomplish this often simple task. Go figure !!!
Ya'll have fun out there today!!!!

-------------------------
The strongest reason for the people to retain the right to keep and bear arms is, as a last resort, to protect themselves against tyranny in government.
Thomas Jefferson

NickD on Thu September 20, 2007 8:43 AM User is offline

Thought they added oil to a replacement compressor just to give you something extra to do, drain it out. Then flush it out with the oil you intend to use, an extra step. You still don't know what kind of oil nor the quantity or if they even put in any oil. I know these tech writers say add two ounces here and there, more or less, when changing a specific AC component, but where do they get this information? As an old engineer, I read what tech writers wrote about my stuff, it's a bad joke, but that is how corporations are run.

Only spec I tend to believe is the total quantity of the oil the system recovers, and the only way to do it right is to remove all the old oil, and especially PAG and can turn into paste. Does take extra time, but certainly a lot less time than replacing the compressor because you fried the old, "new" one up.

My brain really doesn't comprehend how a reed valve can break a belt, assumingly, they can either be blocked closed or open. Blocked closed where a thin piece of tin can stay closed with the power of an engine driven piston behind it isn't very likely to happen. And if it bends open, differential pressures are reduced, must be overlooking something here and we are talking about a belt snapping into two. Not extra drag.

Seized pistons due to lack of lubrication does make sense where all your might on a strap wrench on the hub can't even budge that sucker. Reed valve movement is greatly restricted, somewhat impossible to exceed Young's modulus of elasticity with that small amount of movement, unless the restrictors were never installed. More typically find reed valves carboned up and leaky that were in compressors that went around the block a few times with a condenser loaded bugs, but this is a brand new compressor?

Feel that lack of lubrication makes a lot more sense, especially for a brand new compressor that hardly made it around the block. But just speculation.

HECAT on Thu September 20, 2007 11:52 AM User is offline

Quote
Originally posted by: iceman2555
And the idea that the system was not flushed.....as appalling as it is to many of us....know that a non scientific survey was conducted last year.....and a vast....very large percentage of 'techs' do not flush a system prior to installation of a new compressor. Boggles the mind.....those that should know the benefits....do not accomplish this often simple task. Go figure !!!

Not to highjack this post, but along with the comments from Iceman and Nick regarding flushing...

IMHO:

There are definitely two sides to the basic opinions about flushing with each side presenting technical data and valid reasoning behind their stand for or against. As long as this is debated and a consensus is not reached; the industry as a whole will remain fractured on this topic and some will continue to flush and some will not.

The OEM's do little to support flushing today as; (1) the chlorinated solvents that worked well in the past are now gone, (2) their systems are running longer without problems, (3) it is in their best interest to quickly turn warranty repairs to maintain customer satisfaction levels, (4) and many service decisions are based upon the elimination of variables to provide precise "cut and dry" service procedures, such as total system replacement. The flushing variables such as component designs, equipment performance, chemicals, and the infinite types of failure scenarios seems to be something they have not wanted to or needed to tackle.

However, we do see a change coming; as we are having successes in testing and working with various OEM's to provide solutions for many heat exchanger cleaning and flushing issues as well as beginning to explore potential "retrofit" scenarios as another refrigerant change looms on the horizon.

The aftermarket component suppliers (with the exception of the heat exchanger suppliers) are supporting flushing as many do require it as part of their product warranty statement. Flushing is seen as a way to protect their products performance and eliminate unnecessary warranty claims and replacements caused by "dirty" systems. But unfortunately as with all well and good policies, enforcement is the issue; many of these manufacturers allow for and credit returns regardless of the obvious debris and solvent problems found (i.e. lack of flushing or lack of doing it properly), to maintain or as a requirement of their relationship with their high volume distribution partners. This may be a huge factor in some of these products or remanufactured products being labelled as "junk". If your not doing it right, and you are naive to that fact, after taking the fourth compressor back to the parts store; you will definitely have and be willing to voice, your perception of that brand being "junk".

We also see a change coming in this situation; as we are hearing more and more "rumbling" from many of these manufacturers about how much this practice costs them and their desire to test, train, and support effective flushing methods to promote "do it right" and reduce their warranty costs.

Most of the aftermarket service providers and professionals see the benefit of flushing, but many are confused and "spooked" by this controversy and the costs of effective equipment. Many turn to ineffective and inexpensive options that yield poor results, which only further perpetuates the perception that flushing is, as we have heard it called, a "voodoo art".

This brings me to my "Go figure" questions of the day.

Why is it that a vacuum pump is more of a necessary and required tool than a flushing tool?

Does this mean it is more important to remove air a moisture off the contaminated oil and debris in the system, than it is to remove the contaminated oil and debris?

Is clean oil and quantity needed for reliable performance, or is a guess good enough?

If a guess is good enough, why do other oil circuits have dipsticks and service intervals?

And finally, is the "head in the sand" denial of the existence of contaminated oil and debris the answer?

GO FIGURE!




-------------------------


HECAT: www.hecatinc.com You support the Forum when you consider www.ackits.com for your a/c parts.

FLUSHING TECHNICAL PAPER vs2.pdf 


Edited: Thu September 20, 2007 at 12:01 PM by HECAT

mhfd112 on Thu September 20, 2007 12:14 PM User is offline

He got to put some gauges on it last night, but forgot to bring the results to work so he could pass them on to me. He said he thought these numbers were pretty close though. If I find out they otherwise I will post the numbers he wrote down when he can send them to me.

I’ll take a stab at it here….high side needle jumped around a tad at first but then settled in and were both steady and easy to read.



Idle- High 225 psi/ low 44psi

2k rpm- high 180/ low 38





Ambient was 84 and vent temps with windows and a door open were lower 50’s. When I shut the truck up vent temps fell to lower 40’s


Tim, could you possibly get circumference and diameter measurement of the clutch pulley from a compressor like we used?

Back to Automotive Air Conditioning Forum

We've updated our forums!
Click here to visit the new forum

Archive Home

Copyright © 2016 Arizona Mobile Air Inc.