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Delco, Delphi, or Denso?

58mark on Sat December 08, 2012 6:12 PM User is offline

Year: 1996
Make: Pontiac
Model: sunfire
Engine Size: 2.2

just bought a sunfire with low miles, but the AC doesn't work. Not sure why, but it hasn't worked in years. I want to buy a new compressor (not rebuilt) a drier, and maybe the lines. (lines are only $50 brand new, so why not?)

I'm finding a delco, a delphi, and a Denso all in my price range, but the Denso is about $90 more. Which is the best for a new compressor, and is the denso worth spending extra on?

my plan is to install the parts, and then take it to a pro to have it evacuated and charged. I've done it before and it has typically saved me a ton of money.

My other question is about flushing. when do you flush a system? I want to make sure there's no crap in the condenser or evaporator. is that something they can do while the items on on the car, but after I install the compressor and drier? Or is it better to let them flush it before I install the new parts? Sorry for the ignorance, I've installed parts before but always skipped the flush because an AC guy told me that if the compressor blows on a GM car, orifice tube catches everything before it contaminates the system. Change the tube, and you're fine.

Any truth to that?

I guess I can and should take my car to my AC guy and see if he can tell what's wrong with it before I spend anything, but if it hasn't cooled in years, I'm probably going to want at least a compressor and drier anyway, right?

I know... that's a lot of questions... thanks for you help

mk378 on Sat December 08, 2012 11:50 PM User is offline

Do a few basic checks first. Is the compressor seized (can you turn the clutch plate by hand)? If not seized up, the compressor is possibly still usable. Next is there any pressure in the lines? If there is zero pressure you should do a static pressure test to try to find the leak before taking anything apart.

Edited: Sat December 08, 2012 at 11:53 PM by mk378

58mark on Mon December 10, 2012 3:28 PM User is offline

Took it by the shop today. They said the compressor moves, but they found a leak, so i need at least a compressor and a dryer.

The lines are not original, so they have been changed at least once, so i think ill leave them alone

They are going to do the flush, them i'm going to install the new parts, and then i'll take the car back to them for evacuation and charging

Please answer this question from my original post. If i'm going to buy a brand new compressor and want the best chance for high quality, whichborlf those 3 brands i listed would be the one to buy?

iceman2555 on Mon December 10, 2012 8:17 PM User is offlineView users profile

Since all of these units should be considered 'good' OE replacements...I would go with the lease expensive. The key to this repair is a totally clean system.....a properly lubricated system....a properly charged system and a properly cooled system. Taking short cuts will reduce compressor longevity no matter what brand is utilized. A good system flush is a that they are utilizing a good flush that does not leave a heavy residue and that the system is charged utilizing the latest and greatest recharge equipment. A slight undercharge can effect system/compressor performance/longevity. The hose assembly for this vehicle does not have mufflers or filters and should be able to be reused. Be sure to flush these also. 1996 vehicles were some of the first units to have the high efficiency condensers.....a suggestion would be to replace this unit. They are almost impossible to flush and clean and if the compressor has internal is a very good chance that the condenser could be contaminated with debris. Just a suggestion.
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

GM Tech on Mon December 10, 2012 9:44 PM User is offline

I don't flush when the failure mode is a leak--as a matter of fact, I fix the leak (if compressor- then new seals and new o-rings) then recharge- and get another 10 years out of it. If oil in crankcase of your V-5 is clean- then you shouldn't have to flush anyway-- 95% of V-5 system failures are due to a leak...

The number one A/C diagnostic tool there is- is to know how much refrigerant is in the system- this can only be done by recovering and weighing the refrigerant!!
Just a thought.... 65% of A/C failures in my 3200 car diagnostic database (GM vehicles) are due to loss of refrigerant due to a leak......

58mark on Mon December 10, 2012 10:38 PM User is offline

That's a great tip that I hadn't thought of... look at the oil in the compressor to determine if it needs a flush or not.

By the way, I read bad review after bad review on Delco and Delphi, so I popped for the Denso. I couldn't find a single review with anybody claiming it was shoddy.

If I find anything wrong with the oil, I'll look into a new condenser too. I don't mind spending a little money to do this right. I got the car for a song, and my son is going to be taking it to college next year, so I want the job done RIGHT

iceman2555 on Fri December 14, 2012 10:54 AM User is offlineView users profile

The Denso unit should work great. Keep in mind that lubricant must be added to the compressor body thru the drain port in the case.

GM, question!. I can understand your reluctance to flush for a 'slight' leaker, however, there are several issues that come into play concerning flushing. The majority of the units in the field today will suffer internal damage due to the reduction of lubricant flow when the system is undercharged. This material may not be indicated on the orifice tube, however the material is suspended in the residual lubricant. On the V series, this material could increase wear on the bronze bushing in the swash plate, restrict flow thru the control valve filter screen, or restrict flow thru the control valve metering orifices. This could also result in premature wear on the guide rod bushing/retainers or decrease performance/longevity.

Also please keep in mind that this vehicle is 16 years old. During this time, how many times has it been serviced ? Did the servicing technician add any lubricant to the system when it was serviced? The majority of tech's in the field today will add 1 to 2 oz of lubricant during a 'service' procedure'. Could this extra lubricant present a possible problem for the new compressor install ? You state in your caption about the major cause of compressor failures is knowing how much refrigerant is in the system.....I believe it is just important to know how much lubricant is in the system also. If a system is over charged with lubricant (excessively), then the system can not be properly charged with refrigerant.

I also know that over the years, the repair shop years, that we serviced many vehicles and not all were 'flushed'. Some of these repairs were successful and others were not. It appears that the success rate was greater when the systems were serviced completely.
From the evaluations that I complete each year, the majority of compressor failures are directly related to lubricant type failures. Often debris is located in the suction side filter screens or the suction side of the compressor. This material would have originated from the previous failure.

I stand beside my statement that flushing is a important part of any AC repair...esp a new compressor.

Evaluation of replacement compressor failures, those I complete for my company and those that are completed for various other suppliers and some are OE units, does not stand the test indicated with the statement of 'an additional 10 years' of service. I feel this statement of your personal repair procedures is being disingenuous to the installer that only wishes to complete the repair once. Your expertise is respected on this forum and we are all entitled to our beliefs. Product repair history indicates that a properly prepared/clean system remain operational much longer than a system that has not been serviced properly.

We are beginning to see changes in the OE market that at one time would simply install a new compressor (warranty period) and not flush, no new orifice or accumulator...and flush....what the heck is a repairs (warranty) that encompass a complete system replacement.

Our operational test stands are flushed and cleaned after each compressor test. It is understood that some of the test compressors may fail...and some are quite exciting when they fail...but others make it thru the primary 500 hr test sequence intact....and truly operational. However, when we analysis the lubricant, one would be amazed at the undissolved solids suspended in the lubricant. And remember this is from a compressor that operational at the conclusion of the test sequence.

Thank you for all the very informative information supplied in the past....I simply feel that flushing and cleaning the system is a major part of the repair procedure.

Merry Christmas and Happy Holidays to everyone!!!!

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

58mark on Fri December 14, 2012 10:57 PM User is offline

So from what you said about the condensers being almost impossible to flush, you think I should just pop for a new one? They aren't terribly expensive (75 to $150 depending on brand)

So all that's left to flush after that is the evaporator and the lines.... that doesn't sound too bad.

iceman2555 on Sat December 15, 2012 3:47 PM User is offlineView users profile

It it were my car.....and the cost factor....yes, I would replace the condenser. The replacement condenser should be a parallel flow hi efficiency unit. beware that some companies offer a 'replacement' 6mm piccolo type condenser. DO NOT USE THIS UNIT. It lacks the cooling efficiency of the PFHE unit.
Flushing the evap is a simple task. Even if the correct equipment is not available....check some of the retailers in your area, they may have a flush gun for rental or a loaner. Obtain a suitable flush, a recommendation for your use would be DuraFlush II. Several jobber groups offer this product...a go it is a good cleaner and evaporates very well. Stay away from the oil based flushes.....can cause problems. Be sure to blow FILTERED air thru the evap for about 10 minutes to insure proper evaporation of the flush. DO NOT USE BREAK CLEAN OR MINERAL SPIRITS. Your hose assembly does not have mufflers/filters so a good soak/flush should be sufficient to clean these units.
A major part of your repair should be to have the system evacuated and recharged by a shop with the correct equipment. The use cans and pressures may result in a undercharged system and this will lead to premature failure of your replacement.
Good if you have any questions. We are here to assist as much as possible.

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

Z2TT on Mon December 24, 2012 1:34 PM User is offline

Think of Flushing this way :

You spend money flushing an old condenser.... which is probably about to begin leaking soon.... you will spend more replacing it anyway if it does leak.

If all debris are not flushed out of the condenser, it could cause a comeback.

If a new condenser is not Stupidly expensive.... put it in.... if you have a Serpentine Flow, Upgrade to Parallel Flow by all means.

Some condensers have small passages that are hard to flush through, and all debris may not be flushed out.

For Compressor..... Denso have always been very good quality.... 1st Choice. But what is more important is to make sure the System will not fail again with the new compressor...... remove the reason why it failed in the first place.

- Flush all oil out and start fresh. Add specified amount of oil (Remember new compressors come with oil, so remember to keep that in mind)
- New TXV or O-Tube if Suspected bad... if easy to change just do it
- New Drier, and Good Vac.
- Leak Test.
- Charge.
- Performance Test and note Pressures.

58mark on Fri March 15, 2013 5:56 PM User is offline

Here's an update... 10 weeks after getting the parts (including the new condenser) getting around to doing this job, i talked to my AC guy about doing the flush. He suggested instead of me installing everything and then having to unhook it all to do the flush, he is giving me a good price for him to install the drier, compressor, oriface tube and condeser i already bought, and he'll flush it, install new o rings, and charge it for $275. I don't think you can beat that price for a installation, flush, and charge.

So with the new parts i bought, i'll be out about $650 on the job, but i think i bought quality parts so hopefully this will last the lifetime of the car.

mk378 on Fri March 15, 2013 6:52 PM User is offline

There is no need to flush new parts. It sounds like the only part you're re-using is the evaporator. I suggest you DIY assemble everything and conduct a static (compressor NOT running) pressure test to confirm there are no leaks. Then go to the shop to disconnect and flush the evaporator, reconnect, evacuate and charge.

Edited: Fri March 15, 2013 at 6:54 PM by mk378

58mark on Fri March 15, 2013 7:00 PM User is offline

They are not flushing the new parts.

I was goibg to do what you were suggesting, but for the price be quoted me for labor, i'm just going to let him do everything.

58mark on Sat March 16, 2013 7:56 PM User is offline

Got it back from the shop. Ice cold air, i'm very happy despite it cost me $700 parts and labor, but the car should last for years and this is Texas, so it's worth it

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