[Vwdiesel] 2000 TDI a/c question - and a brief description of

[Bryan Belman]

OK, got the brass manifold gauge set for less then $50 off Amazon.

I see the vacuum pumps to evacuate the system.  when do you need to do this?  How would you know you need to empty the system?
Would you only do this prior to taking the system apart, of course or when replacing seals?

just wondering?

 Bryan Belman, Pt. Pleasant, NJ
04 Jetta Wagon TDI PD, 100hp, 5sp -- running :)
92 Jetta 1.6 Eco-Turbo Diesel -- running :}
82 Diesel Westy 1.9NA -- running :)
70 Type 1 stock Beetle -- Not running :( 




________________________________
From: Val Christian <val at mongo.mongobird.com>
To: Bryan Belman <dieselwesty at yahoo.com>
Sent: Mon, June 7, 2010 12:12:12 PM
Subject: Re: [Vwdiesel] 2000 TDI a/c question - and a brief description of

They won't "rent" them.  But again, they are only $40 or $50.  Good luck 
with the project.

Val


> 
> Great stuff, thanks.=A0 I will see if I can rent the guages from Autozone l=
> ike I did with the 32mm socket for my wheel bearing job.
> I can do this, I hope.
> 
> =A0Bryan Belman, Pt. Pleasant, NJ
> 04 Jetta Wagon TDI PD, 100hp, 5sp -- running :)
> 92 Jetta 1.6 Eco-Turbo Diesel -- running :}
> 82 Diesel Westy 1.9NA -- running :)
> 70 Type 1 stock Beetle -- Not running :( =
> 
> 
> 
> 
> 
> ________________________________
> From: Val Christian <val at mongo.mongobird.com>
> To: Bryan Belman <dieselwesty at yahoo.com>; vwdiesel at vwfans.com
> Sent: Mon, June 7, 2010 10:37:25 AM
> Subject: Re: [Vwdiesel] 2000 TDI a/c question - and a brief description of
> 
> My comments:
> 
> Don't mess with adapting other guages...you can find a set for 134a for abo=
> ut $50.=A0 Worth it, because over the next couple of years you will benefit=
>  more than that by having them.
> 
> Pressures are measured with the AC running, and it will cycle on and off.=
> =A0 You measure while the compressor is engaged, and have to do some human =
> peak and average reading analysis.
> 
> As a general rule, I would get concerned if the high side gets over 240 and=
>  the low side over 35 or 40.=A0 There are exact numbers, but they are depen=
> dent upon environmentals, and even then, there are wide tolerances.=A0 A sy=
> stem can be a little less than ideal, and still work great.
> 
> Your 12oz can...has to evap (which will cool it) and the gas should go into=
>  the low side, while simultaneously monitoring the high side.=A0 Intermitte=
> ntly stop feeding the gas in, and see where the low side is stabilizing.=A0=
>  Shoot for 20 to 30# max, if you can.
> 
> Higher ambients, mean higher pressures.
> 
> The acid test for emptying a freon can is the weight.=A0 Everything else is=
>  an
> assumption with less data.=A0 But if the can is at ambient, and the valve
> is open to the low side while the compressor is on, then the can is probabl=
> y empty.
> 
> I had a friend, just before he got his PhD (education doesn't always help)
> run his caravan over to show me how he recharged it.=A0 He said he put 6 ca=
> ns in.
> He had over 600PSI on the high side, and couldn't understand the look of pa=
> nic on my face.=A0 He had kept adding freon until it stopped getting colder=
> .=A0 It's a wonder he didn't burst hoses driving the 10 miles to my house.
> 
> So get a set of guages...the ones with the red and blue knobs, and hoses.=
> =A0 You can still use a short hose for the low side, with a can of freon.=
> =A0 At some time you will buy a 30# 134a cylinder, and it will take care of=
>  your needs for a long time.=A0 But get the guages.
> 
> Oh, the reason you don't put liquid, jsut gas, into the low side, is that y=
> ou don't want to hydraulic lock the compressor.=A0 =
> 
> 
> Also, on speed, you can do the entire job at idle, but I sometimes rev to 2=
> 500 to see where the pressures stabilize at, becase I figure that's where i=
> t will be running, when I'm going down the road (at least in the IDI).=A0 I=
> 'm not an expert, but I've done this for 30 years.=A0 And the guys who real=
> ly know AC haven't laughed at me...at least to my face.=A0 grin.
> 
> 
> > =
> 
> > With all the great e-mails these past few days, I need to do something ab=
> ou=3D
> > t the=3DA0AC in my 92 Eco Jetta.=3DA0 I have a can of 134a and I know whe=
> re to =3D
> > put it in thanks to=3DA0Nick showing me when I stopped to see him on=3DA0=
> our wa=3D
> > y back up the=3DA0coast from FL.
> > =
> 
> > But, to learn more about the system, I want to do the measurments of PSI =
> on=3D
> >=A0 the high=3DA0side and low side before and after.
> > I do not=3DA0think this gauge needed would be anything special for Automo=
> tive=3D
> >=A0 AC, so as long as I can get my diesel compression tester to properly c=
> onne=3D
> > ct to the high side nipple, that should work, yes.
> > =
> 
> > For the lost side, I can use my normal gas engine psi tester, the one I u=
> se=3D
> >=A0 for beetle motors and stuff.
> > =
> 
> > My Questions.
> > Do I take the PSI readings with the car cold or warmed up and running?
> > =
> 
> > How much do I rev. the motor when putting in the 134a, about 2K
> > =
> 
> > How will I know the can is empty, will there be condinsation on the outsi=
> de=3D
> >=A0 to show or something like a propane bottle?
> > =
> 
> > thanks
> > =
> 
> > =3DA0Bryan Belman, Pt. Pleasant, NJ
> > 04 Jetta Wagon TDI PD, 100hp, 5sp -- running :)
> > 92 Jetta 1.6 Eco-Turbo Diesel -- running :}
> > 82 Diesel Westy 1.9NA -- running :)
> > 70 Type 1 stock Beetle -- Not running :( =3D
> > =
> 
> > =
> 
> > =
> 
> > =
> 
> > =
> 
> > ________________________________
> > From: Val Christian <val at mongo.mongobird.com>
> > To: vwdiesel at vwfans.com
> > Sent: Mon, June 7, 2010 9:33:43 AM
> > Subject: Re: [Vwdiesel] 2000 TDI a/c question - and a brief description of
> > =
> 
> > =
> 
> > Don't measure AC performance by how far people move away from you when yo=
> u =3D
> > arrive.
> > =
> 
> > Put a thermometer in the air stream, on MAX AC, recirculating air.=3DA0 A=
> fter=3D
> >=A0 things stabilize, the air coming out should be below 40F.=3DA0 On my 2=
> 003, i=3D
> > t is usually 34F or 33F.=3DA0 =3D
> > =
> 
> > =
> 
> > If it's 50F or 55F, and the outside air is less than 90F, you definitely =
> ha=3D
> > ve a performance problem.
> > =
> 
> > If it's running 35F and you're just getting very little air, then you may=
>  h=3D
> > ave a diverter not positioning itself, or a vacuum motor type problem.
> > =
> 
> > Val
> > =
> 
> > =
> 
> > =
> 
> > > =3D
> > =
> 
> > > That's why VW Diesel owners are smarter:=3DA0 not only can they fix the=
>  =3D
> > =
> 
> > > system, they can give great, well-written descriptions of the system.=
> =3DA0 =3D
> > =
> 
> > > As far as being better looking as well, that's just a point of fact.
> > > =3D
> > =
> 
> > > I appreciate the explanations from all.=3DA0 Combined with my rough =3D
> > =
> 
> > > knowledge of the system and some half-remembered chemistry class =3D
> > =
> 
> > > knowledge (I ran a supercritical fluid extractor in grad. school--forgo=
> t =3D
> > =
> 
> > > about that), I think I have it.=3DA0 Took me a few days to assimilate i=
> t =3D
> > =
> 
> > > all, though.
> > > =3D
> > =
> 
> > > I always do worry about the big, catastrophically expensive parts like =
> =3D
> > =
> 
> > > compressors in a car with 267,000 miles, but I'll hope for the best.=3D=
> A0 =3D
> > =
> 
> > > Hope is cheaper.
> > > =3D
> > =
> 
> > > What seems to happen is that the airflow through the vents is reduced.=
> =3DA0 =3D
> > =
> 
> > > I normally run the system on fan speeds 1-2.=3DA0 When the problem real=
> ly =3D
> > =
> 
> > > hit, I'd been driving almost an hour on recirculate and when I cranked =
> =3D
> > =
> 
> > > the fan to speed 4, all I got was a lot of noise and very little (but =
> =3D
> > =
> 
> > > cold) airflow.=3DA0 Turning off the recirculate helped.=3DA0 That was b=
> efore =3D
> > the =3D
> > =
> 
> > > added can of 134a, and I've not had to drive a lot since.=3DA0 Tomorrow=
> , =3D
> > =
> 
> > > however, I'll have to make the same trip in even hotter weather.=3DA0 I=
> 'll =3D
> > =
> 
> > > let y'all know.=3DA0 I'll also put on an extra layer of anti-perspirant=
> , =3D
> > =
> 
> > > just in case.
> > > =3D
> > =
> 
> > > =3D
> > =
> 
> > > -Shalyn
> > > =3D
> > =
> 
> > > _______________________________________________
> > > Vwdiesel mailing list
> > > Vwdiesel at vwfans.com
> > > http://www.audifans.com/mailman/listinfo/vwdiesel
> > > =3D
> > =
> 
> > =
> 
> > _______________________________________________
> > Vwdiesel mailing list
> > Vwdiesel at vwfans.com
> > http://www.audifans.com/mailman/listinfo/vwdiesel
> > _______________________________________________
> > Vwdiesel mailing list
> > Vwdiesel at vwfans.com
> > http://www.audifans.com/mailman/listinfo/vwdiesel
> > =
> 
> _______________________________________________
> Vwdiesel mailing list
> Vwdiesel at vwfans.com
> http://www.audifans.com/mailman/listinfo/vwdiesel
>