"Cheap" Harbor Freight elec refrigerant leak detector test - Page 3 - PeachParts Mercedes-Benz Forum

leathermang · #31 07-26-2016, 10:29 AM

While your compressor may have actually split ...
some compressor types have a blow off valve in the body which will react to extreme over pressure...

funola · #32 08-01-2016, 10:47 AM

Quote:

Originally Posted by funola

Got my $10 paypal refund from Banggood. I am impressed! The digital gauge arrived and is being tested for leaks. Hopefully this one will not leak.
The reading is in MPa, 1.014 MPa = 147.068 psi

This pressure gauge/ tester holds pressure for a week so I would trust it. My 85 300D with R152 has been slowly losing cooling performance. The HF elec leak detector did not find any major off the scale leaks, minor triggers are not definitive. Did not find any leaks with dye or soap bubbles either in the accessible places. So, I finally hooked up my pressure tester to the car (leaving the R152) pressurized it with Argon to 150 psi (limit of the digital gauge). I do have a slow leak that averages 0.06 psi /minute, that's 43 psi in 12 hours. Again, did not find any major leaks with the detector, bubbles or dye.
My next step will be to remove the TXV and make adapters to the evaporator and pressure test it alone. If the evap turns out to be leaking, I'll have to decide what to do next. I really don't want to remove and replace the evaporator, not a job I'm looking forward to plus the fact that a replacement evaporator is difficult to get. It is nla from Mercedes and no one seems to have an aftermarket one.

Maybe I'll sell it and buy a Prius with nice cold AC that runs on an electric compressor at 160V and gets twice the fuel economy of the Mercedes.

leathermang · #33 08-01-2016, 10:53 AM

No one blames you for not wanting to remove the evaporator.... a nightmare from what many describe...

Randy · #34 08-02-2016, 10:47 AM

I found my evaporator has a pinhole using one of these, it picked it up in the outlet vent very quickly. Far as I am concerned it is worth the cost if it helps you out one or a few times.

Demothen · #35 08-02-2016, 11:14 AM

Quote:

Originally Posted by Randy

I found my evaporator has a pinhole using one of these, it picked it up in the outlet vent very quickly. Far as I am concerned it is worth the cost if it helps you out one or a few times.

Were you able to have the pinhole repaired, or did you just replace the evaporator?

barry12345 · #36 08-02-2016, 11:29 AM

I do not know the harbor freight price. Around twenty dollars from ebay delivered from China when I picked up mine. There are of course better and more sensitive models but they cost. A lot of refrigeration repair equipment is quite expensive for what it is.

funola · #37 08-05-2016, 03:24 PM

I have been getting to know the HF refrigerant sniffer by using it a lot. It works well for bigger leaks, but for very slow leaks like through a hose, I am not sure if it is conclusive. It alarms when placed close to a certain spot on the hose, but does not show bubbles with Mega Bubbles. The only test I'd trust so far is my digital pressure test set and underwater test where the part being tested is submerged under water. I have finished making adapters from a TXV to isolate the evaporator so I can pressure test it. But I am missing one fitting. It is the #10 beadlock with male nut (on the big hose). Should arrive next week. Right now to pressure test the evap, I have to have that big hose in the circuit. It failed the vacuum test and is undergoing a 150 psi pressure test with R12 tracer. I am hoping the leak is in the hose, not the evap. Until I get the fitting, I won't know for sure.

funola · #38 08-09-2016, 05:13 PM

My digital pressure tester has proved to be very useful. It has determined my evaporator is not leaking. If I believed the HF detector, I'd have a bad evaporator. I will be returning it for a refund It's worst characteristics is that it goes off when the tip is in close proximity to almost anything (like almost touching), refrig. hose, fittings, plastics, metal. It does not do it all the time, which leaves you wondering what to make of it.