Sealers are "nice" to use...but can also damage the A/C system by plugging
up small holes/orifices in the system (won't cool properly). You'll need to
move the dash out of the way and then remove the A/C box (behind the dash)
to get at the evaporator.
>From what you described...it definitely sounds like the evaporator. One
other item you can check...listen to the A/C system while you start it up
(keep the fan on low or medium and the stereo OFF). If you hear a slight
"hissing" noise, that's defintely signs of a leak (low on refrigerant). The
smell is, more than likely, from leaves/dirt/dust/bugs on the base of the
evaporator (yeah...they smell after a while).
If you're going to charge up the system again...you may want to have it
professionally evacuated to remove some of the excess sealer/oil that you've
put in there. However, it may be a useless idea as you already know that
the system is leaking - fix it and be done with the problem (plus...it'll
smell much better). :)
- Bernd
-----Original Message-----
From: owner-dakota-truck@bent.twistedbits.net
[mailto:owner-dakota-truck@bent.twistedbits.net] On Behalf Of Peter Grace
Sent: Thursday, June 16, 2005 3:29 PM
To: dakota-truck-moderator@bent.twistedbits.net
Subject: Re: DML: air conditioner clutch intermittent
My replies are inline:
Bernd D. Ratsch wrote:
>
> Sounds like you have a leak somewhere. Look around at all the lines
> (and at the compressor and condensor) for any traces of an oil film
> (at all the sealing areas). If you don't see any, the common problem
> is the evaporator
> - time to yank the dash and replace it.
I definitely have had a leak for some time.. I'm thinking the leak may
actually have been sealed by this last can of sealer. Evaporator, huh?
How hard is it to replace in a 1997 V6? How much does a new one cost?
> Pressure on the low-side will be high (100-120) when the compressor isn't
on
> (normal)...when it turns on, you should be getting down to the lower side
of
> the pressure gauge (anywhere from 0-20 depending on humidity/temperature)
> and the high-side should be around 200-300 (depending on system/vehicle).
I
> don't trust those "Red/Yellow/Green" gauges as they don't show you exact
> pressures and you can't check the high and low sides at the same time -
> makes for a much easier diagnosis when you can see both sides.
Yeah, the gauge I have is pretty crappy. I'm by no means an automotive
expert, so I don't know if I would go all-out for a dual
highside/lowside gauge. The one I have gets the job done dirty-like, my
guess is if I want actual numbers I really ought to pay the diagnostic
charge!
>
> The compressors rarely fail (have had to replace them but only on higher
> mileage vehicles - 80-90K+ miles) and only on occasion when the compressor
> actually failed (but it is a possibility)...my bet is still the evaporator
> though.
148,905 miles for me! As long as she still turns over, I'll continue to
ride her. I don't think it's the compressor either, because it does
seem to be following a pattern (more on that below.)
>
> Do NOT keep putting those "fix all" refrigerants into the system as 2001+
DC
> vehicle already come with dye in the system - no need to add any. Adding
> the "R134a with Sealer/Dye/Conditioner/Oil" will hurt the system more than
> you think. The drier/accumulator will plug up prematurely, the evaporator
> lines and condensor lines will plug up, and the internals on the
compressor
> can plug up as well. Having too much oil in the system will also degrade
> A/C performance.
I'm probably going to switch to adding just the straight R134a they sell
at advance auto parts until I can drum up the cash to get whatever leak
is fixed. I wonder if the evaporator is where the leak is?
The complete symptom list is (besides a leak) -- I'll be driving down
the road and the AC will be cranked and putting out ice cold air. Then
at (more or less) exactly the same spot on my normal commute, I smell
a really musty/dank type odor and the air out of the vent turns humid
and hot. If I turn the AC off for like 10 mins (put the switch in OFF)
and turn it on, the AC will (sometimes) start working again for another
couple mins then get hot again. I'm guessing the musty odor is a sign
that something's shutoff and all that humidity it was trying to purge is
somehow coming back into the cabin?
Any pointers would be appreciated!
Pete
This archive was generated by hypermail 2b29 : Fri Jul 01 2005 - 09:48:06 EDT