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I’ve had a search around the forum and can’t find an answer sadly.
The AC in our JB74 SZ4 appears to have packed in and I’m struggling to get the the bottom of why.
Here’s what I know so far:
- AC rad fan runs
- Compressor clutch engages and disengages as far as I can tell.
- According to the local Suzuki dealers, AC gas levels are as they should be.
- High side piping is hot and the low side is cool
- Cabin filter isn’t blocked
My theory is that the AC compressor has gone, as it’s very noisy. It has always been on, as I don’t believe in turning AC off and the other half has been educated about it (NO IT DOESNT MAKE IT COLD 🙄)
Have any of you come across a similar issue with the JB74 AC system?
The A/C compressor has to be working for the high side lines to be hot and the low side lines cool, refrigerant has to be circulating, if it wasn't, there would be no heat transfer, and that is what is making the high side lines hot.
I am not certain how the dealership determined that the "gas levels were as they should be" or even what that phrase means, is it quantity (measured in lbs/ozs) or pressure (measured in psi), and I want to point out that pressure measurements are impacted by local conditions, such as the temperature both inside & outside of the vehicle.
Also most dealerships in my corner of the world (the Caribbean, where we are heavily dependent on air conditioning) don't have techs with the required experience to deal with air conditioning issues.
Given the fact that there is a temperature differential between the lines the system has to be moving heat from somewhere and if it's not the cabin of the vehicle, I would question whether or not the air flow in the cabin is being routed through the evaporator or around it - there are "blend doors" in the HVAC system that may be incorrectly set.
Perhaps have the system evaluated by an a/c specialist.
My assumption is that they have connected it and measured pressure/refrigerant quality?
I forgot to mention there is not condensate coming from the drain, which leads me to believe that there is some issue with either the compressor or the evaporator. I have a can of evaporator cleaner to see if that makes a difference, however I’ve not got around to getting it done yet.
AC is not something I’ve ever had a problem with before, mainly because old Defenders generally don’t have it!!
As yours is an SZ4 it has the mechanical Aircon. On the old Gen3 which all have the mechanical Aircon it is possible to kick the actuator cable off the end of the air flow paddles, this means the airflow can be blocked.
I have just looked under my LCV (which is an SZ4 in disguise) and it has the mechanically adjusted paddles visible on the drivers side by looking up. Check that they operate when the controls are rotated.
Martin
Martin
2003 M13 early KAP build.
3" Trailmaster lift with 1.5 Spacers on front
Customised winch bumper and roll cage
235/85R16 Maxxis Bighorns on 16" Rims, 4:1 Rocklobster, Rear ARB locker and on-board air
Corrected arms all-round, rear disks, Recaro seats and harnesses
I’m really at a loss, I may take it to get regassed, that’s the thing I can think of now, prior to replacing the compressor!
The term "regassing" as related to an automotive air conditioner, generally relates to adding more refrigerant to bring it up to the correct level/quantity, which is why I was asking about this earlier, the dealership supposedly did this, although, we don't know how.
What's puzzling me here is why was there no definite diagnosis from the dealership.
