Automotive Air Conditioning Information Forum

Hi,

Wanted to say this a great site and have learned an enormous amount.

Background…

I have all tools, gauges, flush kit, filtered dry shop air. I will source nitrogen from a welding company if needed. My son & I purchased the above car with 140,000 miles. The condenser had a hole and all refrigerant has been lost. I have no idea when the system last functioned. It has a Denso compressor. Which turns freely. All the lines appear original.

I debated just replacing the condenser, orifice, o rings and dryer. Then flushing system. But everything has so much age, I have decided to replace everything including all lines and evaporator. I plan to keep the car for the next 5 to 10 years.

This is a dumb question but do I need to flush the new lines, evaporator, condenser with anything? Are they good to install from box?

Should I replace the high side and low side switches? I was planning on it. Any reason not too?

Thanks
Patrick

Good project. Corvettes are tough to cool, as you have learned from your lurking.
You're going to do all that work and NOT change out a comp with 140K on it? A 27 YO comp that prolly has a dried up shaft seal? Get a price for all your stuff from Tim here at AMA (ackits.com). His prices are verrry competitive. In my mind a comp with more than 100K is suspect. There are numerous posts here where the poster has changed out everything but the comp and then been very disappointed. In fact we just had a LeSabre in that same boat.
I typically do not flush new parts. When someone flushes anything, it can be difficult to properly dry out the flush solvent. Of course, these are my opinions and the way we do things here.
I am on the fence about your switches.
Which refrigerant?
Lets let some other consultants chime in here.

I wouldn't Crack open an instrument panel and HVAC module unless I really needed to. Mostly the IP, hard to get it back together properly and not have a mystery squeak or rattle.

No need to flush new parts, also no need to replace pressure switches that are good, probably no harm either.

If you are of the mindset to get a new system, I'd suggest a new compressor, those Denso 10PA compressors were ok, they wear off their piston coatings with use, if you want another 10 years, best to replace now when the system will be clean. Buy new Denso not rebuilt. Buy once, cry once. Those rebuilt units will make you cry every 9 months

I don't flush new parts, either. When you open the boxes, just make sure all the ports and/or tube ends have plastic caps on them. If not, I return any components without the caps.

The specifications for your Corvette are 32 ounces net weight of R-134a, and 8 fluid ounces of PAG-46, or whatever the under-hood decal says.

Thanks for the replies. I’ll replace the Denso compressor with new.

I hadn’t thought about buying the parts here. But I will price it out. I think I’ll leave the switches for now.



I was making my parts list and had 2 more questions.

I noticed an option for the expansion valve as the stock ac delco and a “variable”. I was going to order stock, would the variable be more effective?


Where can I source the “putty” to help seal the box the condenser is in from the engine compartment and what if anything should I use to seal the box to the fire wall? Silicone?

I plan to order everything Monday!

Thanks!!

Avoid the variable orifice. They do not work.
You might try sticky backed foam tape for your sealing. Hardware stores or the 2 big box (blue one,orange one) would prolly have it.
Clean off the surfaces with lacquer thinner for better adhesion. Mineral spirits is oily and leaves a residue

Thanks going with original GM.

case2001 wrote: ↑Sun Jul 17, 2022 5:23 pm Thanks going with original GM.

Good decision. Over the past few years, some aftermarket TXV's have proven to be defective, requiring the job to be done over. Ask me how I know

Ok. All parts ordered. Should be arriving next week.

I’m going to begin dissembling the box that contains the evaporator so when the parts arrive I will be ready to assemble.

I will post updates as I go along.

Is there any reason to keep the old compressor?

Thanks

case2001 wrote: ↑Wed Jul 20, 2022 6:07 pm Is there any reason to keep the old compressor?

I always hold onto all the replaced components, including the compressor, for a little while in case I should need something off of them. Once I'm satisfied that the system is running well, I discard the old parts.