High Side R134a Schrader Valve Leaking
 

I charged up my AC for a weekend jaunt and found that the schrader valve on the high side is leaking pretty good. I can't even put the cap back on it's so much.

As I see it, I have two choices:
1. Take the car to a place and have them remove the existing refrigerant. Then purchase the removal tool and hopefully find a correct replacement schrader valve and replace the valve myself. Then recharge the system.

2. Take the car to a place that has that special tool to replace the schrader valve even on a live system.

I like the idea of option 2 better, but don't know if I can find a place to do this.

Is this a pretty common thing? What are peoples' experiences?

BTW - this is the stock compressor on my '87 that a PO had converted to R134a.

Matt

Valve.
 

No biggie.

Go to any PEP Boys, buy a valve removal tool.($10).

Remove the refrigerant (if any)/replace the valves/pull a vacuum/ recharge.

I just replaced the A/C in our '86.

pm me as needed.

Gerry

Work with Gerry. You can buy kits that have an array of schrader valves.

would it make sense to start by using the removal tool to try and tighten the valve (and potentially eliminate the leak) before removing it and evacuating the system? Or does the leak automatically equate to a compromised system?

Absolutely and a good idea (won't work if valve is bent from over-tightening fittings on a manifold service set, butt definitely worth a try).

Not if there is still pressure in the system that would keep outside air out; if all refrigerant gas has leaked out, then air, moister, etc., would have entered and a vac needed. Given the OP's description of the leak, probably a full vacuum do-over would be needed now.

NO
goto the local HVAC supply house and just buy the tool. I have several of them.

here is one. I prefer the one with the 90 shut off valve.
for $70 you will probably pay someone that much to recover the refrigerant.

this tool is great for doing super heat/ sub-cooling

Just get the tool from Pep Boys and tighten up the valve. I bet it's loose. If you do not hear a hiss when you are done then you are good to go.

Sometimes I find the needle itself is leaking then it must be replaced and vacuumed.

But before that, open and closing several times could also work to re-seat the needle's seal.

When the valve is leaking, I can take a very small needle nose pliers, grab the needle in the valve, and pull slightly. The act of doing this stops the leak until I let go. That makes me think the valve is probably leaking instead of just loose.

The valve is no longer leaking but I'm sure it's due to the pressure having dropped low enough.

I see there are a bunch of different sizes available for replacement. Does anyone have experience with which size is the correct one?

T77 - the link appears to not have come through. In doing some research on this, there seem to be many different types of valves (standard, JRA, etc.), so I want to see about getting the right tool.

While converting my 87 911 A/C, I used a Slime 4-Way Tool (2004-A) from Home Depot for less than $2. It has a long enough Schrader fitting to reach into the adaptor.

yep they make high pressure schrader valves and yes the tool works for low and high-pressure fittings

I just used it on my 930, although the system was empty.
I replaced both valves before starting the vacuum.

just find an HVAC supply house

Have heard it suggested that Schraders can be damaged by manifold couplings pushing their shafts in too far. I checked "push in" in my system in '14. Forgot exact measure but (my) Schrader had just a hair of end play remaining (after my coupling was turned in fully.) Given different Schrader dimensions and different couplings... it may well be fact that Schrader's can be damaged by turning a coupling in too far.

http://forums.pelicanparts.com/uploa...1470143505.jpg


(Don't recall what story is behind this pic.) Look closely at right-hand Schrader. Would that seal correctly? Would coupling work correctly with it?

http://forums.pelicanparts.com/uploa...1470143581.jpg

no.
the "nail head" looking part can push in all the way down until the "head of the nail" stops on the threaded part of the valve.

the green part is the seal where the valve seals against the body that holds it.
the part on the bottom is where most leaks happen. that is the seal for where it opens and closes.

Hey Harold - THANKS for this. I ran over to Home Depot and got this exact tool, also for under $2. I stuck it onto the valve and turned it at least a half turn. I'll try and charge the system tomorrow, but hopefully that did the trick. If that didn't do the trick then I'm out $2 and I have to move on to R134a recovery, but at least I'll know.

Matt

Does this one work?
https://www.amazon.com/Mastercool-81490-R134A-Remover-Installer/dp/B000KITSMI

Also note that I have read that Schrader's do not always seal totally and that is part of the reason why they have a pretty tightly fitting cap. I had a slight leak in mine, put a cap on it and problem has disappeared.....but there is a tiny puff of refrigerant if you take the cap off.

Seems cheaper to try that than to empty the refrigerant just to replace the valve.

Dennis

yes. there should be a rubber Oring in the cap.
also why when HVAC guys service your system they usually just replace the valves.
I have a nice big bag of them

so where do I go to get some new shrader valves for my 88. are they usa or metric??