Landcruiser 80 aircon

thanks mate

the compressor cuts in fine as soon as you push the button but wont cut off as the a/c cycles itself

If the system is cycling it means the compressor IS switching on and off. All cycling is done by activating a compressor. Something in the observation of the problem is not quite right.

If the compressor keeps running it points to the thermostat control (either a mechanical or electronic one) which is too far away from the air evaporator core in the dash chamber and being to far from sensing core temp, it will continue to run the compressor. That then freezes available water onto the core and although air can get through some section, the rest may be a block of ice which can't impart coolness to the air. So it effectively runs HOTTER and seems like the system isn't working, but it is. Just not as designed.

I would check if the temp sensing position is correct, maybe remove some of the ducting and clean out any crap in which builds up against the core unit.

Make sure the internal blower fan works as it should respective to switch speed position.

My mechanic uses some stuff that glows under UV light. Showed me one time on my Subaru. Couldn't see anything until he pulled out the light wand. Stood out like the proverbial dogs whatis...

That sounds like the same stuff.

I was very suprised when he pulled out the condenser how much dust and crap was sucked into the heat exchange fins.

Cheers

Anthony

Yes, it is a TX valve (Thermostatic expansion). And the condenser is out the front, where the hot refrigerant gas condenses to liquid form. The refigerant then vaporises at the TX valve at the inlet to the EVAPORATOR which is the under-dash "coil" and returns to the low pressure side of the compressor.

Thanks Zippo


Wouldn't it be great if I could go back and edit the correct term in.

Given it is on the low pressure side this is probably the reason it lasted for a while after regassing.

I know once they found the leak in the evaporator and replaced it - no more issues. It was only persistence on the part of the shop I sent it to that found the leak. Toyota just kept putting gas in.

Cheers

Anthony

Anthony, sorry if that sounded patronising - it was simply meant to clarify things. And yes, an edit button (as found on many forums) would certainly be a welcome addition for most of us - myself included.

No! Not at all Zippo.

Just saying it would be good if I could edit the correct term into my response so that it made sense.

Unfortunately it will always be incorrect - so if someone only reads my response they get incorrect info.

Glad someone could clarify it - that's why I put the (?) because I wasn't certain of the term.

Does my theory of losing the gas slowly make sense? If it was on the high pressure side, I would expect to lose it much quicker.

When the aircon guy showed me the evaporator and the glove box with his UV light, you could see quite clearly where it leaked. It was only the tiniest of holes.

Cheers

Anthony

What he said.

If the compressor is NOT cycling then the evap is icing up.

Thanks mate

Ill get my mecho to hook his guages back on to it and give it another check sounds like ill have to pull the evaporator out and give it a clean also

Cheers

hi
if the high pressures are reading low
low pressures reading low
system is down on refrigerant
static pressure with both hoses connected is around 100 psi for normal system
The condenser [in front of radiator ] may be suffering from a lot of stone chips and once again highly likely its leaking from this .
MANY AIR CON LEAKS DONOT HAPPEN ALL THE TIME
SOME LEAK ONLY UNDER CERTAIN CONDITIONS

Be prepared for tx valve ,evap , condenser and hoses ,receiver drier , many orings
lube all joints with fridge oil
The evap to suction hose connection may be frozen together [this happens from age and the constant temp cycling ]
Remove compressor and have flushed & reoiled at local aircon shop

If the compressor is Nippon these are able to be reconditioned by NDenso aust
These are fairly reliable

swampy