a/c guru's, apply here...

[feral4mr2]

cruising down the hi-way enjoying the a/c on a hot day, i feel the a/c compressor 'cycle' i guess you would call it. eg. feel like it's engaging, then disengaging and engaging again.

the air out the vents goes warm (ambient temp), though the a/c compressor still triggers on/off with the a/c button. can hear and see the compressor engageing.

the system is filled with the green dye stuff that i cannot see has leaked anywhere from any of the joins in the a/c system/pipes.

now before i go off and spend a fortune at a auto sparky i am asking here incase this symptom is some little electircal gremlin i just cant see? like why it might of switched on/off repeatedly a few times and then not cool anymore. it is my understanding that if all the gas went out of the system the compressor should not be able to engage?

cheers if anyone can help.

[Z2TT]

Hi,

I had a N13 Pulsar that did this, It was a A/C Switch with a bad contact.

Your correct, if there was not enough gas in the system, the A/C Compressor would not engage.

[StuC]

there is a high/low pressure switch whihc tells the compressor to cut in/out to keep the pressure within a certain range. if there is no visble leaks (check with a UV light as that what the dye is for) then check for loose contacts, shorts etc on the compressor power switch/wire istelf. It could also be a faulty sensor, if thats the case the gas will need to be removed to replace or could even possibly be a stuck TX valve (expansion vlave) which is casuing the pressure to build up excessively and kick off.

Start with the possible leak and go from there.

[Dale]

Check the compressor actually stays on and doesn't cut out after a second or two

Put your hands on the lines (with compressor running - even short the compressor clutch wire straight to battery), one of them will be warm/hot, the other ice cold

Check there is gas in the system by pressing one of the valves briefly to see if anything comes out - alternatively if the compressor definitely is running check the looking glass on the drier to see if there is gas passing through it

Sounds like its low on gas if the compressor is definitely engaging - or as Stu said the TX valve could be stuck

[2jzhilux]

did this happen on a hotter day and then ok on cooler days or is it not working at all now
could be overgassed and as outside temp has risen so gas has expanded.

Also could be tx valve sticking

[feral4mr2]

thanks for the replies fella's.

2jz, it was a hot day heading home from site on tuesday, but yea, doesnt cool at all now. how would i check for overgassing?

dale, the compressor clutch stays engaged while the a/c button is on. though i 'think' the compressor sounds a little different to how it did when it was cooling. like it isnt loaded up anymore?

this TX valve doobie. if it is faulty will it still allow the clutch to engage?

thanks again all. i do like cruising in comfort.

[fixeruperer]

only way you can tell its over gassed is with gauges or as soon as you turn the a/c on the a/c clutch triggers on/off/on/off or when it starts to warm up, but it would have done this before

warm day and gas expanding does this aswell but it would hav done it before in hot weather.
is you condenser fan working ?
tx valves can freeze up and not let gas pass through, it would be close to the evaporator in line with hi pressure.

get some gauges on it and see what its doing or if it has any gas, pity your not closer.