purging the yellow charging hose

Friendly format provided to inquire about automotive a/c systems.
Archived Forum

Moderators: bohica2xo, Tim, JohnHere

Post Reply
User avatar
msrichmond
Posts: 50
Read the full article
Joined: Fri May 17, 2024 8:49 am
Location: Portland, Oregon

purging the yellow charging hose

Post by msrichmond »

In the videos I have seen, purging the yellow line of hose is done by either loosening the fitting on the end of the manifold gauge set or pressing a schrader valve on the gauge set itself.

In my case, I hear air coming out, but I never see the puff of white refrigerant that the videos show. If the tap is working properly, how long should it take to purge the line via the valve on the MGS?

I weighed the can after this operation and I was down a couple of ounces, but never saw a 'poof'.
User avatar
Cusser
Preferred Member
Posts: 948
Joined: Sun Apr 24, 2016 6:29 am

Re: purging the yellow charging hose

Post by Cusser »

msrichmond wrote: Sat Jul 06, 2024 4:46 pm In my case, I hear air coming out, but I never see the puff of white refrigerant that the videos show. If the tap is working properly, how long should it take to purge the line via the valve on the MGS?
I'd say about 3 full seconds.
tbirdtbird
Preferred Member
Posts: 1448
Joined: Sat May 02, 2020 1:48 pm
Location: Texas

Re: purging the yellow charging hose

Post by tbirdtbird »

Forget all about the “white puff of refrigerant”

YouTube vids can be very deceptive and anyone, no matter the training, can post anything they want

From trying to assemble all your questions and posts I think you have been watching some very misleading vids.

Should anyone wish to learn more auto AC, all they have to do is start reading all the postings and answers on this board and go back in time doing so. There is a wealth of knowledge on this board like nowhere else, from some really top-notch consultants
When considering your next auto A/C purchase, please consider the site that supports you: www.ACKits.com
User avatar
msrichmond
Posts: 50
Joined: Fri May 17, 2024 8:49 am
Location: Portland, Oregon

Re: purging the yellow charging hose

Post by msrichmond »

tbirdtbird wrote: Sun Jul 07, 2024 8:07 am Forget all about the “white puff of refrigerant”

YouTube vids can be very deceptive and anyone, no matter the training, can post anything they want

From trying to assemble all your questions and posts I think you have been watching some very misleading vids.

Should anyone wish to learn more auto AC, all they have to do is start reading all the postings and answers on this board and go back in time doing so. There is a wealth of knowledge on this board like nowhere else, from some really top-notch consultants
I am a 35 year participant in a board like this for classic Fiats, www.mirafiori.com and I've posted advice exactly like this. I have learned a great deal from being here already.

Here are my next steps. I am going to reinstall the expansion valve I took out thinking it might be blocked. It isn't but I did find a torn o-ring. Once I get my evaporator back in, I'm going to pull a vacuum again. When I try charging this time, I am going to use a Robinaire side tap to bypass the infernal self-sealing valves and tap on the small cans I have. I'll start with the engine off and use a full can on the blue side with gas, not liquid. If I can't get that can to nearly empty into the system, I will give up and take the car to a professional. If I can get some actual quantity in, I'll rotate the compressor by hand as some vendors advise, start the car and cross my fingers. It is headed to the high 90s in Portland today, so if I can get past this roadblock I should know pretty quickly whether or not I have AC or not.
tbirdtbird
Preferred Member
Posts: 1448
Joined: Sat May 02, 2020 1:48 pm
Location: Texas

Re: purging the yellow charging hose

Post by tbirdtbird »

Good luck to you!
When considering your next auto A/C purchase, please consider the site that supports you: www.ACKits.com
User avatar
msrichmond
Posts: 50
Joined: Fri May 17, 2024 8:49 am
Location: Portland, Oregon

Re: purging the yellow charging hose

Post by msrichmond »

I am certain that refrigerant is getting into the blue hose. I don't think it's getting out.

Here is a photo of my MGS hanging on the wall after I closed the blue valve after losing about two ounces to purging. The pressure is all in the hose still, and in fact, my high side vacuum is still showing.

I'm headed to AutoZone to rent a different MGS. If that does not work then I would suspect the schrader valves on my service ports.
Attachments
MGS.jpg
MGS.jpg (221.77 KiB) Viewed 2390 times
tbirdtbird
Preferred Member
Posts: 1448
Joined: Sat May 02, 2020 1:48 pm
Location: Texas

Re: purging the yellow charging hose

Post by tbirdtbird »

I would be more suspect of the couplings on the MSG.
The cheapo sets are famous for have the wrong tolerances machined into the parts. Then what happens is that the shraders on the car do not get properly depressed.
I myself have had this problem and I should have gotten my MSG from Tim when my old one finally died.

Be warned that rental stuff often has been abused especially by ppl who have no idea what they are doing.
Everyone says, hey how bad can AC be, anyway, well just shove in some Freon and be on our way!!!

If only it were that simple!
When considering your next auto A/C purchase, please consider the site that supports you: www.ACKits.com
User avatar
msrichmond
Posts: 50
Joined: Fri May 17, 2024 8:49 am
Location: Portland, Oregon

Re: purging the yellow charging hose

Post by msrichmond »

tbirdtbird wrote: Sun Jul 07, 2024 3:01 pm I would be more suspect of the couplings on the MSG.
The cheapo sets are famous for have the wrong tolerances machined into the parts. Then what happens is that the shraders on the car do not get properly depressed.
I myself have had this problem and I should have gotten my MSG from Tim when my old one finally died.

Be warned that rental stuff often has been abused especially by ppl who have no idea what they are doing.
Everyone says, hey how bad can AC be, anyway, well just shove in some Freon and be on our way!!!

If only it were that simple!
Guilty. I bought another one from Harbor Freight. $69 with two cans of R134a thrown in for free. It worked.

The one I bought was sold by Rock Auto (I had a gift card from my family). It was not cheap - a Four Seasons 59199. Unfortunately I bought it November and their warranty is 120 days.
Post Reply