Automotive Air Conditioning Information Forum (Archives)

torque395 on Tue August 03, 2010 1:40 AM

Year: 1996
Make: Chevrolet
Model: Suburban 2500
Engine Size: 6.5L TD
Refrigerant Type: R-134a
Ambient Temp: 90
Pressure Low: 0
Pressure High: 0
Country of Origin: United States

I have been pondering the though of flushing my AC system with gasoline or lacquer thinner or perhaps denatured alcohol or something of the sort. I was thinking gasoline because I could use an electric fuel pump to circulate the gasoline through the system to throughly flush the system out, even in reverse and attaching a filter to it to capture anything it might flush out. And its cheap (compared to anything else) Then blowing it out with dry air or having someone blow nitrogen through it to dry it out. Gas should evaporate with just as little residue as anything else so I dont see any harm in that.

I know not to flush the compressor, or the accumulator/drier or the o-tube or TXV and to replace the said parts with new parts when going back together (except the compressor unless needed).

Any thoughts on this ? I dont do much AC work so I cant justify buying a flushing machine or anything and I dont really want to pay someone else out the backside to do it for me. I question the quality of work I get at a shop anyways, no one does anything as good on someone elses vehicle as they would for their own.

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1996 Chevy Suburban 2500 4x2 6.5L Turbo

HECAT on Tue August 03, 2010 6:23 AM

Just remember that chemistry experiments can cause unexpected reactions. Are these chemicals evaporative? Yes, but that is not all to be considered. What about material compatibility? Will any seals and hoses used be damaged by these products? Are these products suitable (miscible, compatible) with the PAG and POE oils, or will they react with the oils and turn them into goo? Blowing out these products will create a highly flammable and potentially explosive aerosolized mist cloud. So does it really all dry out? A/C cleaning products and the process will always leave trace residues, it is about limiting the residues and being sure the residues are compatible so that they will not degrade the fresh oil or cause problems (chemical, acidic, corrosive reactions) over time. Regardless of the chemical chosen, not having a method (equipment, tools) to properly apply the chemical into the multiple parallel paths of these system components is not going to properly clean them. No matter how good the chemical, a soak an blow will not get it done. Good luck with your experiment.

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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: Tue August 03, 2010 at 6:27 AM by HECAT

Cussboy on Tue August 03, 2010 6:44 AM

Don't use gasoline, too dangerous.

iceman2555 on Tue August 03, 2010 11:18 PM

Quote
TextAny thoughts on this ? I dont do much AC work so I cant justify buying a flushing machine or anything and I dont really want to pay someone else out the backside to do it for me. I question the quality of work I get at a shop anyways, no one does anything as good on someone elses vehicle as they would for their own.

I question the quality of the repairs of someone who would consider the use of gas as a flush agent. But then, just when I thought I had heard it all.
Pay attention to HECAT's post...he knows his stuff about flush chemicals and procedures. This is truly an experiment and it is felt a path that will lead to a very serious issue with system contamination.
There are very few shortcuts that lead to a successful AC repair....and dollars spent to accomplish the repair properly are dollars well invested. Locate a reliable shop in your area.....a trust worthy shop and let them repair your vehicle....or purchase the correct parts and tools to facilitate the repair in a proper manner.
Forget the gas, alcohol and other chemicals that were not designed or formulated for an automotive AC system...there is a specific reason the OE's and all compressor manufacturers no not use or suggest to use some of these chemicals....most do not work....and most can result in serious system contamination.
If these chemicals produced the perceived results....then HECAT as wasted many dollars in his R&D for a good flush chemical. Heck, Karl...forget all that stuff...run down to RaceTrac and buy your chemicals...or over to Walgreens and get some of that magic flush in the bottle...yep...the one in the first aid section.....small bottle.....low cost.....no special equipment required...heck Karl...ya gonna be out of business very soon....!!!!!!!!
Gas and denatured alcohol...two of the most flammable substances around....and just think....blowing this stuff out of the parts...lots of air.....lots of highly flammable vapors.....this might make the late nite news....or at least a good utube video.......

Do the job right...do all that is necessary and hopefully you will only have to do it once. Forget the shortcuts and cost cutting measures.....do it or get it done correctly.

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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

NightOwl on Thu August 05, 2010 12:57 AM

Hey partner not that it really needs to be said again you are an adult but listen to the guys who already posted.

Gasoline + pressure + heat = explosion or fire (Basic Chemistry)

the problem is worse with alcohol and with that you won't even see the flames just feel the burn.


Then you'll end up in one of my colleagues ER's where they'll try and maybe fail to save your life if you manage to breath it.

Sincerely NightOwl

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Courage is not the absence of fear. Courage is being afraid and doing your duty anyway.

chris142 on Thu August 05, 2010 9:00 PM

Wow. Ya stick with fast evaporating AC flush.

77shovelhead on Fri August 06, 2010 1:48 AM

torque395,

I thought blowing the system out, without flushing, with compressed oxygen was a good idea.

Thanks to the guys here who reminded me about the oxygen+oil=BOOOOOOM.

Is there a top 10 most dumb ass award. If so where did I place in it?



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Quality is never an accident it is always the result of intelligent effort.

iceman2555 on Fri August 06, 2010 5:26 PM

Simply 'blowing out' a system with air, nitrogen or whatever gas is chosen is not an acceptable method to 'clean' or 'flush'. The system should be cleaned utilizing a good liquid flush. Chemicals that exhibit low boiling/vaporization points are not the best flush chemicals to use either.

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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