Common place for tiny A/C leak in 1995 K1500?

sneakingfart · Jul 20, 2024

95Noobie said:
The parts store had a little bitty screwdriver tool to remove the valves but it looked just like the tool I had at home to remove bike tube valves. I have some new valves so I'll see if I can swap them out and clean good after. It would seem to make sense to do that before adding dye since the system is empty now.

Since the system is empty, I agree with just replacing the valves. They are cheap. Do both the low and high pressure side. If I recall correctly, the high pressure side is not the regular bike valve like the low pressure side, but you can buy it on RockAuto for around $10. But I am going to bet that is not your problem.

If this was my truck, I would replace the condenser and compressor right off the bat, especially if your compressor is original (and 29 years old). Do the orifice tube as well, it's like $3 and very easy to replace. The condenser is very easy as well, you just have to remove the grille. Replace every o-ring that is easily accessible. Ideally all of them, but some are hard to reach. Just buy an AC o-ring assortment on Amazon, and some Nylog lube. The manifold that connects to the AC compressor uses copper crush washers, replace those as well, don't reuse them like I tried (and failed) to do. I also replaced the low pressure and high pressure switches, and o-rings. I did confirm a leak at the condenser using dye, and my compressor was oily. No leaks so far, about 6 months in.

sneakingfart · Jul 20, 2024

95Noobie said:
agreed so my first step is going to be to try to inspect in the charge port or even below the schrader valve to see if there is even dye in the system yet.

Rather than putting in dye separately, I just refilled with r134a that had dye already in it. That way I know that there is dye in the system, and should I suspect another leak, I can wait until dark and look for it, rather than spending money refilling the system and then looking for it.

Also, AC work is incredibly easy. I am not a mechanic (not even close), and I did it all myself. Rather than paying an AC shop, pick up a set of inexpensive gauges and a vacuum pump (both of mine are from Harbor Freight), spend about 20 mins watching a YouTube video, and do it all yourself. The only difficult thing on this truck is if you need to replace the evaporator. The dash has to come out. But that is not a common source of leak.

GoToGuy · Jul 21, 2024

Schrader valve. Are high pressure, most have Teflon seal. Not just any air pressure valve.
Good tip: Any time you service through a schrader valve, after disconnect, check to ensure the valve has shut and is not leaking. Use whatever method works for you, liquid soap, Windex, leak check, spit ( when your a thousand feet from the shop). When you start checking sometimes it's surprising how many have really sloooooow leak. :waytogo:

95Noobie · Jul 25, 2024

I recharged with R134-a preloaded with dye. Compressor started up and A/C is blowing cold. Confirmed with the shop that they did put dye in (and now I put more in) and they could not find a leak. I'll run it a bit more and see if I can find it. I have a nice UV pen light now too. I can't detect any hiss when opening the high and low side access caps. I put soapy water in the access ports filling them up and can't see any persisting bubbles. I was going to see about going to parts store today to get replacement valves and replace anyway.

I replaced my a/c climate control panel with an aftermarket one. The button for recirculation mode doesn't light up anymore. How can I tell if it is going into recirc mode, in other cars the speed of the fan or volume of the air flow picks up when it is on recirc mode? The blend doors between dash, front, lower vents is working as I cycle through them. The A/C on/off button is working properly as is its indicator light.

I'm going to order a replacement a/C control panel and swap them out even if it is just because it bugs me that the light doesn't work on the recirc button..

someotherguy · Jul 25, 2024

The recirculate flap is in between the firewall and the blower motor housing; you can see it if you poke your head underneath the dash, or stick a mirror on the floor to look up. It should move upwards to seal against the fresh air intake in the cowl when you activate recirculate mode. In the down position where you can see it resting against the grille-like area of the lower portion of the box, it's allowing fresh air in from the cowl.

This isn't the greatest pic as it's a broken box from crash damage, but you can see the flap, this is the side of the box facing the firewall, with the blower motor housing behind it. The grille area faces the floor. It was during a rebuild of this truck that I discovered why it always got cold air inside the passenger floor in the winter, regardless of the heat setting.

You must be registered for see images attach

Richard

1998_K1500_Sub · Jul 28, 2024

95Noobie said:
How can I tell if it is going into recirc mode

The blower fan noise is very noticeable when the recirc is functioning. And @someotherguy showed you where to find the door, so you can check visually.

scott2093 · Jul 28, 2024

95Noobie said:
The button for recirculation mode doesn't light up anymore.

Light bulbs in there?

95Noobie · Aug 1, 2024

1998_K1500_Sub said:
The blower fan noise is very noticeable when the recirc is functioning. And @someotherguy showed you where to find the door, so you can check visually.

turns out the chinese panel was bad even though it was brand new.

One helpful tip. On ebay you can buy a transition/transfer cable from the original 1995 plugs to the newer body style plugs that connect to the climate control panel. That adapter was very handy as it gave extra length of wire to work with while taking the old control panel out and also allowed me to use the very common and affordable newer control panels. Well, those newer panels are also chincy and prone to fail, but at least now that I have the adapter cable it was very easy to swap a new a/c control panel in and the recirc button works as does the recirc door. I can send links if desired.

1998_K1500_Sub · Aug 1, 2024

95Noobie said:
One helpful tip. On ebay you can buy a transition/transfer cable from the original 1995 plugs to the newer body style plugs that connect to the climate control panel.

Please post a picture and perhaps the item description, e.g., from the eBay listing
:waytogo:

This may further help others, years from now.

95Noobie · Aug 1, 2024

1998_K1500_Sub said:
Please post a picture and perhaps the item description, e.g., from the eBay listing

This may further help others, years from now.

Good idea.

This is the item description from ebay, you can use these search terms and find others for sale on ebay.

New 16233143 Heater Climate Temperature Control Adapter Wire For Chevy Silverado

Ebay link for the above item

That adapter will allow this below module to work on the 1995/older style chevy trucks. You just have to get the one that matches your set up. Note on the first one it does not have the button for rear defrost.

Amazon climate control board

This one has the button for rear defrost.

control board with rear defrost

Common place for tiny A/C leak in 1995 K1500?

sneakingfart

OBS Enthusiast

sneakingfart

OBS Enthusiast

GoToGuy

I'm Awesome

95Noobie

I'm Awesome

someotherguy

Even more awesome in person

1998_K1500_Sub

Nitro Junkie

scott2093

I'm Awesome

95Noobie

I'm Awesome

1998_K1500_Sub

Nitro Junkie

95Noobie

I'm Awesome

Similar threads

Latest posts

Staff online

Members online

Forum statistics

Share this page