1991 A/C Evaporator Tube

[KOOLC4]

Started my car up today and was backing out of my garage then a loud pop and hissing from the passenger side under the hood. Shut it down and checked things out. The coolant temp switch on the evaporator tube for the A/C condenser had broken off at where the threaded fitting/valve comes up. Couple of questions for you guys. Is there anywhere I can find a replacement tube? It is discontinued, of course, and only one listed that I can find is on EBay, White Racing Products, and the picture is not what mine looks like, no fittings for switches. They don't answer their phone so I am suspect already of doing any business with them. Any help please would be appreciated. Thanks, Keith

[32valvesftw]

I have no idea about finding a new tube, but maybe you can get the switch out with a sharp chisel and thread a new one in.

[KOOLC4]

The threaded part broke off inside the switch and it backed right out. It contains a valve that looks like a tire valve on a wheel. In other words it broke at the pipe level so the valve needs to be somehow attached back on the pipe such as soldered/welded or maybe some type of JB Weld?

[WVZR-1]

I'd call locally to older established AC repair facilities and ask about "aluminum brazing" - being an R12 system I believe TIG isn't an option. There's very likely differing opinions but ....

I wouldn't remove the line until I found a shop that says they can repair and I'd be inclined to let them do the removal for the repair. It's entirely likely that they might want to splice a section.

[-=Jeff=-]

Can you post a picture of the line you need?

[KOOLC4]

Thanks for the replies. It's the bottom pipe/ hose, #15 in the diagram.

[-=Jeff=-]

That is the high pressure hard line.. I would think the L98 for 90-91 should be the same..

So is the fitting completely gone? or the inside threads are gone where the schraeder valve was?

[WVZR-1]

That is the high pressure hard line.. I would think the L98 for 90-91 should be the same..

So is the fitting completely gone? or the inside threads are gone where the schraeder valve was?


Actually NOT - it's '90 & '91 LT5 only

[-=Jeff=-]

huh.. wonder why?

I cannot get to mine to look at it.. a picture of the actual broken line would help

[KOOLC4]

The threaded portion of the pipe with the valve in it broke at the base and was inside the switch/sensor. Here is a picture.

[-=Jeff=-]

ok.. I see what happened now..

Since the system has to get recharged. wonder if if that could be TIG welded back on..

[KOOLC4]

I was thinking that may be an option as well. The valve screws out just like a tire valve so the heat can be kept from damaging it but the wall is pretty thin. What a weird thing to have happen. Must have been subjected to some side loading on the attached switch in it's lifetime. The car only has 19k miles but it had been updated to modern refrigerant a few years ago.

[WVZR-1]

ok.. I see what happened now..

Since the system has to get recharged. wonder if if that could be TIG welded back on..

I mentioned brazing and I recall years ago that it was mentioned by a good friend that you don't TIG R12 aluminum tubes - I did find a similar reference today but didn't note it. Many years ago we had an AC specialty shop and that's where I'd have sent the fellow. They did many specialty projects for myself and others late 70's and early 80's.

I mentioned splice also and it's possible an AC shop would want to eliminate the port as it is now and do their own.

Use the "phone" - then drive the car to the shop - show them what's needed!

OP mentions a refrigerant change so I'd say the technician is maybe a contributor to the issue!

[KOOLC4]

I would tend to agree with the tech contribution especially if this port with the Schrader valve is used for the changeover.

Thanks for the great input. I will let you guys know how this turns out.