Automotive Air Conditioning Information Forum (Archives)

nthach on Wed July 21, 2010 1:27 AM

Year: 1991
Make: Lexus
Model: LS400
Country of Origin: United States

Long story short, a local AC shop didn't evac the system sufficiently and some seals failed during the 6 years of time from when I did the original retrofit. I'm in the process of flushing out the condenser and evaporator, as well as replacing every seal along with the receiver/drier and expansion valve since I noticed some freezing up of the suction line from the evaporator.
1) I ordered a shaft seal kit and the body gaskets for the Denso 10PA20C compressor but I did not get a seal protector sleeve. Can I improvise this or pray that I can find this tool locally?
2) I know Hecat will persuade me to get the DIY Pulsator - but that's a topic for another day. I flushed out the condenser and the evaporator with Quest's flush and clean(the aerosol version is very similar to Hecat's brew), then with Klean-Strip Green lacquer thinner(which does not contain methanol). I did final flush the evaporator with CRC Lectra-Motive which is basically chlorinated brake cleaner I can get in California. Is this the wrong way of flushing out the heat exchangers? Is there anything I can get locally to flush out these components before installation?

HECAT on Wed July 21, 2010 7:49 AM

Quote
Originally posted by: nthach
2) I know Hecat will persuade me to get the DIY Pulsator - but that's a topic for another day. I flushed out the condenser and the evaporator with Quest's flush and clean(the aerosol version is very similar to Hecat's brew), then with Klean-Strip Green lacquer thinner(which does not contain methanol). I did final flush the evaporator with CRC Lectra-Motive which is basically chlorinated brake cleaner I can get in California. Is this the wrong way of flushing out the heat exchangers? Is there anything I can get locally to flush out these components before installation?

1. Even with the proper seal install sleeve it is always wise to purchase 2 shaft seals.

2. I am not here to persuade anyone to purchase proper tooling, the information, product, and support is available here; it's your choice. You can purchase the specialty tools to do specific jobs, or buy a new component; both from this forum sponsor. I sold all my tooling to rebuild compressors; it would my choice to purchase a replacement compressor, rather that change the seals. Liquid flushing of today's components requires special tooling to produce volume flooding and velocity action; a "poof" will not get it done.

Spray can, lacquer thinner, and brake cleaner; is this the wrong way? In my opinion, most probably a yes; but I have no idea how these chemicals were applied. Did they wash all the oils out? Will these chemicals completely dry out, leaving only lab detectable trace residue? Will remaining residues of these chemicals adversely effect the repaired system more than others (chlorinated)? Could there now be an excessive oil/solvent mix remaining in the component(s)?

Yes, there should be suitable chemicals available locally, and I am not saying (without deeper research) that one of the chemicals you have chosen would not work, but you would needs a few gallons. Once a suitable flushing agent is chosen, the next step is proper application; a "poof" will not get it done.

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


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

FLUSHING TECHNICAL PAPER vs2.pdf 

nthach on Wed July 21, 2010 2:10 PM

The system has no debris - the lines and the heat exchangers looked clean and free of major debris. I'm flushing the system to get rid of excess oil. Thanks for your advice, I'm going to order another seal as a backup.

HECAT on Wed July 21, 2010 4:13 PM

Just make sure you give it the extra effort to make sure the components are completely DRY.

FYI: I looked at the Quest aerosol MSDS and it does have some chemical similarity to the HECAT flush. But, it uses a very high concentration of the d'limonine, that the HECAT flush contains a very small amount of. There is a reason we use a very small amount of this very aggressive solvent, it has to do with its oily residues. Too much of a good thing, in my opinion. Based upon the chemical composition regardless of the concentrations, I did also find some impossibilities (BS) in the Quest MSDS.

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

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

FLUSHING TECHNICAL PAPER vs2.pdf 

nthach on Wed July 21, 2010 4:30 PM

Quote
Originally posted by: HECAT
Just make sure you give it the extra effort to make sure the components are completely DRY.



FYI: I looked at the Quest aerosol MSDS and it does have some chemical similarity to the HECAT flush. But, it uses a very high concentration of the d'limonine, that the HECAT flush contains a very small amount of. There is a reason we use a very small amount of this very aggressive solvent, it has to do with its oily residues. Too much of a good thing, in my opinion. Based upon the chemical composition regardless of the concentrations, I did also find some impossibilities (BS) in the Quest MSDS.

I'm doing multiple hits with compressed air - I wish I had the luxury of a shop-spec compressor but I can always give my old job a visit to blow things dry in the detail shop. I'm making do with a 1.7HP 20 gallon Husky oilless which makes the job slower and unbearably NOISY. My plan is several blow cycles ending when the compressor is pumping up. I'll repeat this until I cannot smell much of the solvent. I can still smell and blow out some perc from the evaporator and the fruity smell of the "green" lacquer thinner from the condenser. I have hit both already a few times.

I'm thinking about buying the DIY Pulsator for the future when I have a AC job on one of the family cars.