I have a substantial leak in my 2001 Honda Civic. I though it was the service port valves, since when I undid the service port plastic caps, some gas hissed out of them. I ended up replacing a pipe, because new valves were still hissing in the pipes. I suspect corrosion did them in. With the new pipe, there is no more hissing.
Pulling a vacuum showed a gradual leak to ambient pressure in about 30 minutes. That is too large a leak. I know conventional leak detection is pumping refrigerant into the lines with perhaps a dye leak detector or chemical sniffer. I have found neither of those methods as accurate or successful as I’d like them to be. I also am uncomfortable with using expensive and environmentally harmful Chemicals as a leak detection tool. R134a prices have also shot up. It was $17 for a small can.
Vacuum isn’t so great for determining where the leaks are - pressure is. I don’t own an air compressor, but I thought, what about using my simple and effective bicycle pump? I use that manual push pump for inflating my car tires to 40psi. Perhaps I can pressurize the AC lines and use the soap and bubble method to fine leaks.
I have already sourced a shrader valve to NPT 1/4” on Amazon. It’s only $8. I can use an adapter from NPT to get to gauge set threads. Then it’s just a matter of pumping air in until I get 40 or so psi, and spray all over the system to find leaks.
Anyone ever heard of this? I will post pictures on Friday, when I plan to do this.