RE: [DMCForum] Here it comes again... the R134 conversion
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

RE: [DMCForum] Here it comes again... the R134 conversion



Excellent. This is what I needed. A good starting off point. I will report
back when I start this project.

> -----Original Message-----
> From: Dave Stragand [mailto:dave.stragand@xxxxxxxxxxxxxxx]
> Sent: Monday, March 15, 2004 2:58 PM
> To: DMCForum@xxxxxxxxxxxxxxx
> Subject: Re: [DMCForum] Here it comes again... the R134 conversion
>
> Not hard if you follow the instructions, and use the proper tools as
> specified in the email.  I've done similar conversions on many cars
> without issues.  The best bet is just to pick up an R134a conversion kit
> at Pep Boys -- it has the hose, 2 cans of R134, and the necessary
> fittings.
>   ----- Original Message -----
>   From: Travis Goodwin
>   To: 'DMCForum@xxxxxxxxxxxxxxx'
>   Sent: Monday, March 15, 2004 1:59 PM
>   Subject: RE: [DMCForum] Here it comes again... the R134 conversion
>
>
>   I can do just about anything on the car but I have never touched an AC
>   system. How would you rate this conversion as far as difficulty?
>
>   > -----Original Message-----
>   > From: Dave Stragand [mailto:dave.stragand@xxxxxxxxxxxxxxx]
>   > Sent: Monday, March 15, 2004 1:18 PM
>   > To: DMCForum@xxxxxxxxxxxxxxx
>   > Subject: Re: [DMCForum] Here it comes again... the R134 conversion
>   >
>   > >From my FAQ:
>   >
>   > This is a fairly complete checklist for the conversion based on
>   > Sanden/Sankyo's own instructions, material gathered from the web, and
> the
>   > wisdom of those DMC owners who have already completed this procedure.
>   > 1) If the R-12 vehicle air conditioning system is operational, run it
> at
>   > idle with the A/C blower on high speed for five (5) minutes to
> optimize
>   > the amount of oil in the compressor.
>   >
>   > 2) Recover all R-12 refrigerant from the vehicle's A/C system.
> Evacuate
>   > the A/C system for at least thirty (30) minutes to a vacuum of 29 in.
> Hg,
>   > using R-12 equipment, to remove as much R-12 as possible from the
> residual
>   > mineral oil.  Don't just dump the old R12 into the air.  If you really
>   > don't want it, at least let a service station vacuum it out.  They
> will
>   > generally take it very happily, as it is quite expensive, and you
> won't be
>   > polluting.
>   >
>   > 3) Remove the compressor from the vehicle, noting the placement of all
>   > shims and washers, and the routing of hoses and wires.
>   >
>   > 4) Remove the compressor oil plug and then drain as much mineral oil
> as
>   > possible from the compressor body.
>   >
>   > 5) Drain mineral oil from the cylinder head suction and discharge
> ports
>   > while turning the shaft with a socket wrench on the clutch armature
>   > retaining nut.
>   >
>   > 6) Remove the existing R-12 receiver-drier or accumulator-drier from
> the
>   > vehicle and discard.  Allow as much oil as possible to drain from the
> A/C
>   > hoses. Blowing them out with an air gun on moderate pressure is okay.
>   > Back-flushing the lines is recommended. Plain old mineral spirits
> swished
>   > around in the compressor and backflushed through the lines will remove
>   > contaminants and old mineral oil. Make DARN, DARN sure that you get
> ALL of
>   > it out of the system, and I do mean ALL of it.  Mineral spirits can be
>   > explosive, but a great many a/c shops still use this technique to
> great
>   > effect. I would recommend drying everything out with clean dry air
> from a
>   > compressor for quite a while (hey, air is free, right?) Commercial a/c
>   > flushing chemicals are also available which will do the same while
> being
>   > safer, but they can be pricey.
>   >
>   > 6) Replace any O-rings on the receiver-drier or accumulator-drier
> joints;
>   > check and replace other O-rings that have been disturbed. You really
>   > should replace them with the new green ones -- they work very well for
>   > both R12 and R134a.  If you are converting to R134, new reports
> suggest
>   > that you do -not- need to change all of the O-rings to different
> materials
>   > as thought earlier. However, I would recommend changing anywhere you
> have
>   > disconnected a joint, just to help seal better. They're cheap anyway,
> and
>   > cheaper than having to do it again because of a leaky seal.
>   >
>   > 7) Replace the accumulator-drier with a new R134a compatible unit
> which
>   > contains XH7 or XH9 desiccant. Make sure that you get one with "XH7"
> or
>   > "XH9" dessicant, not "XH5" -- there should be a sticker on it stating
> as
>   > such.  XH7/9 works just fine with R12 and is necessary with R134's
> Ester
>   > or PAG oils.  As a cross-reference, a 1986 Corvette accumulator-drier
> is
>   > perfect. Factory Air brand part number 33191 dryer is ideal, and runs
>   > about $55 at AutoZone.
>   >
>   > 8) While you have the accumulator-drier removed, now is a good time to
>   > replace the orifice tube.  Always replace it 'just because'.  The type
>   > used on the DMC is just a standard "white" GM orifice tube used for
> many
>   > years on many GM models, and the cost is less than $2. (Any parts
> counter
>   > person should know what you mean when you ask for one). There are some
>   > newer variable orifice tubes claiming to work better with R134a, but I
>   > have not read very much about them, and I'm a little wary of their
> claims.
>   >
>   > 9) Perform any necessary repairs to the compressor or A/C system.
>   >
>   > 10) Using the original refrigerant oil quantity specification, add
> [INSERT
>   > QUANTITY HERE] ounces of Ester oil to the compressor. Ester oil is
>   > preferable to PAG in a retrofit, as it will mix fairly well with any
>   > remaining mineral oil.  It was originally thought this was not the
> case,
>   > but consensus nowadays is that they mix satisfactorily.  Ester is also
>   > less corrosive than PAG.  As an additional benefit, R-12 will also
> work
>   > with Ester should you ever wish to convert back.  If you follow these
>   > guidlines, all you would need to do to revert to R-12 is completely
> vacuum
>   > all R134 out of the system and then simply reinstall R-12.
>   >
>   > 11) Replace the compressor oil plug O-ring with an new O-ring.
>   >
>   > 12) Reinstall the compressor oil plug. The plug seat and O-ring must
> be
>   > clean and free of damage. Torque the plug to 11-18 ft lb (15-25 N m,
> 150-
>   > 250 kgf cm).
>   >
>   > 13) Change any seals at the compressor ports to new seals.
>   >
>   > 14) Reinstall the compressor to the A/C system, paying close attention
> to
>   > the placement of shims and washers from step #3.
>   >
>   > 15) Disable the R-12 service fittings to prevent any refrigerant other
>   > than R134a from being used. You do this by permanently installing
> R134a
>   > quick-connect service fittings to the A/C system.
>   >
>   > 16) Vacuum the system for AT LEAST forty-five (45) minutes to a vacuum
> of
>   > 29 in. Hg once the lines are cleaned, the new drier installed, the
> correct
>   > amount of Ester has been poured in the compressor body, and the whole
>   > system is ready to go. Harbor Freight makes a cheapy high-vac pump for
>   > $15. You can hook this up to a spare R134 can adapter hose ($5) to
> make
>   > the correct fitting for attaching to the car. And yes, you MUST
> evacuate
>   > the lines. This is the most common mistake people have in
> retrofitting. If
>   > you don't get that vacuum down in the system, there is no way the air
> is
>   > going to blow very cold.
>   >
>   > 17) Charge the A/C system with R134a. Generally, about 5% (by weight)
> less
>   > than the R-12 charge amount is required. That means just a little over
> 2
>   > pounds for a DMC.
>   >
>   > 18) Check the A/C system operating parameters. The system should
> function
>   > correctly within acceptable limits of temperatures and pressures --
> this
>   > will ensure that the correct amount of R134a has been charged.  I
>   > purchased at a small R134 gauge at Pep Boys for less than $5.  It
> looks
>   > much like a tire pressure gauge.  It tells you the system pressure in
>   > terms of low/good/high/danger. Likewise, they have a small & cheap
> "meat"
>   > thermometer that will tell you vent temps inside the car.
>   >
>   > 19) Replace all R-12 compressor labels with retrofit labels per SAE
> J1660
>   > in order to provide information on the R134a retrofit which has been
>   > performed.  In other words, you really should put a sticker on there
> that
>   > says it's R134a.  The recommended places are on the compressor and the
>   > accumulator.
>   >
>   > Additional notes:
>   >
>   > - In extreme circumstances when expected cooling performance cannot be
>   > achieved and high discharge pressures are experienced, it may be
> necessary
>   > to add more condensing capacity to the A/C system.  I believe PJ Grady
>   > sells a larger capacity condenser for our cars.
>   >
>   > - Sanden has the service manual up for our compressors online at
>   > http://www.sanden.com/support/servicemanual/index.html
>   >
>   > -Dave
>   >
>   >   ----- Original Message -----
>   >   From: Travis Goodwin
>   >   To: 'DMCForum@xxxxxxxxxxxxxxx'
>   >   Sent: Monday, March 15, 2004 12:46 PM
>   >   Subject: [DMCForum] Here it comes again... the R134 conversion
>   >
>   >
>   >   I desperately need to do this before Pigeon Forge. Last summer I was
>   > lucky
>   >   that I didn't have to drive it much since the engine was dismantled.
>   > This
>   >   year is a different story.
>   >
>   >   Bill, I know you're the man when it comes to this. Any advice on
> where
>   > to
>   >   start?
>   >
>   >         Yahoo! Groups Sponsor
>   >               ADVERTISEMENT
>   >
>   >
>   >
>   >
>   >
>   > ----------------------------------------------------------------------
> ----
>   > ----
>   >   Yahoo! Groups Links
>   >
>   >     a.. To visit your group on the web, go to:
>   >     http://groups.yahoo.com/group/DMCForum/
>   >
>   >     b.. To unsubscribe from this group, send an email to:
>   >     DMCForum-unsubscribe@xxxxxxxxxxxxxxx
>   >
>   >     c.. Your use of Yahoo! Groups is subject to the Yahoo! Terms of
>   > Service.
>   >
>   >
>   >
>   > [Non-text portions of this message have been removed]
>   >
>   >
>   >
>   >
>   >
>   > Yahoo! Groups Links
>   >
>   >
>   >
>   >
>
>
> --------------------------------------------------------------------------
> ----
>   Yahoo! Groups Links
>
>     a.. To visit your group on the web, go to:
>     http://groups.yahoo.com/group/DMCForum/
>
>     b.. To unsubscribe from this group, send an email to:
>     DMCForum-unsubscribe@xxxxxxxxxxxxxxx
>
>     c.. Your use of Yahoo! Groups is subject to the Yahoo! Terms of
> Service.
>
>
>
> [Non-text portions of this message have been removed]
>
>
>
>
>
> Yahoo! Groups Links
>
>
>
>

Yahoo! Groups Sponsor
ADVERTISEMENT
click here


Yahoo! Groups Links



Home Back to the Home of PROJECT VIXEN


Copyright 2006 ProjectVixen.com.  All rights reserved.

Opinions expressed in posts reflect the views of their respective authors.
DMCForum Mailing List Archive  DMCNews Mailing List Archive  DMC-UK Mailing List Archive