Jump to content

A/C Compressor


Bushwack

Recommended Posts

Via e-mail, Marck has been very helpful regarding the replacement of an a/c compressor. But I'd like to bring the subject up for discussion on which would be the right compressor (what specs to look for). I know of at least three different compressors that have different specs that are Reatta compatible with price points ranging from $232.00 to over $575.00 (from different manufacturers - all new).

So...cost aside, what would be the specs to look for in a compressor and does anyone have a personal preference?

Link to comment
Share on other sites

HR6 is pretty much an HR6, difference is reliability/garentee. So far I have been through three new compressors on one car this year and the latest needed a clutch plate replacement after 100 miles. First two seemed to have a common factory defect (faulty weld).

Only recommendation would be to use the later (90-up) HR6 even if you have to change the plug.

Link to comment
Share on other sites

My question is for preparation in the event I need to replace the compressor on a new purchase (pictures will follow after a spit-shine). For now, heat works OK. The A/C blows cool (not cold) and I hear a click every few seconds as if its trying to recycle. Really haven't done much more in regards to researching the problem. The 'Service A/C' light is on. Maybe only a re-charge is needed (not R134A). But I would like to prepare for worse case scenario and get schooled on the differences in compressors.

Link to comment
Share on other sites

A compressor does not care what it is pumping, the system is designed to cut out if the pressure gets too low to carry lubricant to the compressor or if the pressure gets too high (about 350 psi).

Used to be lubricants, mineral oil for r12 and ester for r134 were what was incompatible and flushing was required to clean out all of the old lubricant but modern lubricants can be used with either. As long as there is enough lubricant in the system (8-10 oz for a Reatta), it is happy.

Most common problem is seal break down in 20+ year old compressors usually where the shaft goes through the casing though I replace all O rings as a matter of course.

There is apparently a timer involved and I start with an empty system by adding as much from a can as it will take. This usually gets you to 45-55 psi static (want about 100 psi static at 90F). Then I start the engine and add freon when coompressor is running for about 5 cycles, shut the engine down and restart then same until first can is empty and start second.

Usually about halfway through the second can the compressor is long cycling (10-15 seconds on) but is not blowing cold, takes at least another 1/2 can before air at outlet is in the low 50s and rest of third can to get down to the high 30's at speed, that is enough for me.

Sign you are about a can low is a low refigerant warning at 40+ mph that goes off at stop.

This is all with 134a which is what I use today. Do not claim to be a professional but this year has been a real learning experience.

Link to comment
Share on other sites

On my '88 Seville (same compressor as Reatta) I went with Delco which came with a 12 month warranty. At month 14 the compressor crapped out, according to my mechanic it was leaking through the compressor body itself(?).

Having learned a lesson of sorts, went with the Four Seasons brand which came with a 24 month warrantee.

Link to comment
Share on other sites

At one point I would use nothing but Delco. Any more I don't know what is quality and what isn't. No wonder shops charge $800 to replace a compressor, they must figure on a certain number of returns and when a new compressor comes apart inside, a complete flush is needed to remove all of the pieces - is an all day job on a cool engine.

Link to comment
Share on other sites

At one point I would use nothing but Delco. Any more I don't know what is quality and what isn't. No wonder shops charge $800 to replace a compressor, they must figure on a certain number of returns and when a new compressor comes apart inside, a complete flush is needed to remove all of the pieces - is an all day job on a cool engine.

Quotes have ranged from $875 - $1,100.

Back to specs on a compressor, I thought a compressors' power requirements might be determined on the interior volume of a car. If I was building a 2,000 sq. ft. 1 story home, I know that I would need a 5 ton compressor to cool the house. But there are variants of a 5 ton compressor. I would think the same compressor specs for a Reatta can't be used for a LaCrosse.

Link to comment
Share on other sites

Ok I know that this will cause a good deal of argument, but when my 90 only cooled and was not cold, still running R12 I simply used freeze 12. That was a year ago and it is still going strong. I figured that at some point in time I would need to either replace the R12 with R134a and a new compressor or use R12 which is pricy around here or prolong the agony and use freeze12. Mine works fine for the time being. Good luck

Chuck Kerls

Link to comment
Share on other sites

If it works, don't fix it. As to compressor capacity, they are rated in cubic inch displacement like an engine. AFAIR the HR6 is about 10 cid. The system AFAIR is rated around 36,000 BTU (three tons). Dual air as found in minivans uses a single compressor/condenser with seperate evaporators and fans.

Link to comment
Share on other sites

2 years ago the dealer installed a AC Delco comptessor on my 1989 Riviera. It came with a Lifetime guarantee. Last year it became noisy so they replaced it at no charge with a continued Lifetime guarantee. As info the waterpumps also carry a Lifetime guarantee.

Link to comment
Share on other sites

Guest Mc_Reatta

Freeze 12 was designed to be a drop in replacement for R 12 so you shouldn't have any problems with using it.

Eventually the seals will wear out in your compressor and you will have to replace it. When that happens you can decide what you want to do for a replacement or upgrade.

Think the governing factor for designing the AC in a vehicle is fitting the evaporator into the dash. Once the design specs are determined for that, then the rest of the components fall into place. Compressors and accumulators are not the design critical components. They can handle a wide range of system volumes as does the orifice tube. For best efficiencies the condenser needs to be matched to the evaporator size and the properties of the refrigerant.

That is why when a system is converted from R 12 to 134, the same compressor, orifice tube, and accumulator are used since there is no need to. The evaporator can't be changed since there is no ability to fit another size into the dash. The condenser should be changed to one that is about 10% larger but unless you are willing to find a suitable replacement and custom install it, you just have to use the original one and suffer the efficiency loss from having an optimum sized one.

Just stick with the standard HR6. With the current state of lack of quality control provided by the manufacturers, there is not much point in going with any particular name brand. As others have suggested go with someone that that at least will offer a good warranty and stand behind it. Then you may suffer like Padgett did and have to replace one 3 times to get it to stick but at least he only paid for the compressor once. We are all at the mercy at the ability of the manufacturer to produce a quality product, but there is little insight into where the vendor you purchase one from actually has it manufactured for them.

The toughest decision you need to make is what refrigerant you want to use. That and whether you catch the compressor before it spews black death into the system will dictate the oil to use and what steps need to be performed to do a proper change over.

At the present time and into the future, I would be less inclined to switch from R12 to R 134. Either stick with R 12 or decide on something like environsafe as an alternative to 134.

Link to comment
Share on other sites

An HR-6 is an HR-6. Only differences are in pulley size, clutch electrical connector, and port orientation.

I've had GREAT luck with the Chinese compressors I pick up for around $200.

I also had the great fortune of picking up a Delco for $95 recently for Carol's Deville.

Only problems I've ever had (sorry Padget) were with remans.

Link to comment
Share on other sites

Guest Mc_Reatta

The standard Enviro-Safe does not need a vacuum pulled, and it does not become caustic if moisture is present. In fact if a vacuum is pulled on a system, it is to be released prior to charging. Their newer industrial version can be charged into an evacuated system but doesn't have to be.

Link to comment
Share on other sites

Guest Richard D

Even though Padgett had a run of bad HR6's from Tech Choice, I got lucky. Replaced mine abour 18 monthes ago, kept it R-12 with estercool oil and have had no problems. Plus down here when engine is running so is the A/C. I received a new HR6, accumulator and orfice tube for $165.00 with one year warranty. Go to resources and look them up, for price break mention Reatta forum.

Link to comment
Share on other sites

Guest Richard D
Might mention the bad ones were for an 88 with the blade terminals.

In fact if you do call them ask if the HR6 problems have been cleared, they will probably answer you honestly.

Link to comment
Share on other sites

Guest Richard D

It is a sticky near the top of the forum, It lists various suppliers of Reattae parts and services. Many are Reatta owners and on the forum.

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...