mountainman Posted June 14, 2012 Share Posted June 14, 2012 Ok comanche friends. My first thread is a tech question. :wrench: Is the AC compressor supposed to cycle on an off with the setting on max AC? As in, is that the factory setups programming? Or should it just stay on constant like all newer cars do? The system is mostly all new parts, all sealed up tight, and vacuumed it down for an hour, and then no leaks after 1 hour of sitting. filled with R12 and have 30 on the low side and 250ish on high side at idle. Whole thing seems to work as it should, just that when its idling and your standing there watching the gauges.... it runs maybe 30 seconds.. then comp kicks off.... then 30 seconds.. comp kicks on. Perfectly timed cycles over and over. Seems like thats what they meant it to do. BUT if the comanche AC gurus say, NO it should be on 100% of the time... then i need to figure out what the deal is. Thanks for any info/help. Dave Link to comment Share on other sites More sharing options...
HOrnbrod Posted June 14, 2012 Share Posted June 14, 2012 Don't know what year your rig is, but they changed compressors in 1991. My 91 cycles as you described. Link to comment Share on other sites More sharing options...
mountainman Posted June 14, 2012 Author Share Posted June 14, 2012 Mine is a 91 pioneer/4.0 HO. :) Its HOT in vegas so I'm just making sure its at 100% operation level. I build and restore cars for a living and am extremely detailed. Right now its blowing 38-40 out of the vents and i want it as cold as i can get it. :) My neighbor is an AC guy and so when he was over and i was working on it... he mentioned.. "I never seen a system that cycles like that". Should be on 100% and i was like.... well its my first jeep so ill ask the forum guys. lol Link to comment Share on other sites More sharing options...
cruiser54 Posted June 14, 2012 Share Posted June 14, 2012 Should not be on 100% or it will freeze up and blow hot air. 38-40 out the vents is as good as it gets. Run it. Link to comment Share on other sites More sharing options...
Harley Posted June 15, 2012 Share Posted June 15, 2012 Wow, somebody else from Vegas :thumbsup: I think we may be the only two here. It isn't that bad here. I have yet to fix my AC. roll the windows down and you'll be just fine! lol Link to comment Share on other sites More sharing options...
mountainman Posted June 15, 2012 Author Share Posted June 15, 2012 :eek: another vegas manche! Dude if you need help let me know. i can help you get your AC goin pronto. I build cars for a living. Ill be lifting mine soon and have a list of stuff for it. So we could go wheelin and have a manche pic session. hehehe. Pm me anytime. :cheers: Link to comment Share on other sites More sharing options...
aaronbtxnc Posted June 15, 2012 Share Posted June 15, 2012 :drool: Did you ask a question, because I keep getting distracted trying to read this thread Link to comment Share on other sites More sharing options...
Harley Posted June 15, 2012 Share Posted June 15, 2012 :drool: Did you ask a question, because I keep getting distracted trying to read this thread It's a Vegas thing. Link to comment Share on other sites More sharing options...
ParadiseMJ Posted June 16, 2012 Share Posted June 16, 2012 You're very photgenic. Is there a picture of you WITH your Jeep?? Link to comment Share on other sites More sharing options...
danbyrambler Posted June 16, 2012 Share Posted June 16, 2012 Should not be short cycling - hard on compressor & clutch - 40 deg indicates the compressors doing its job - new compressor? If so, correct type/amount oil for r12? When everything's new can be tough to run down - Jumpered the high & low pressure switches? - could be faulty cut out switch - continue to do it if you increase rpm to around 2K? - New expansion valve? - Got a FSM for the thermistor values? Tried using temp control to raise output temp a little? Still do it if blower motor is set to next to high? :hmm: Link to comment Share on other sites More sharing options...
Eagle Posted June 16, 2012 Share Posted June 16, 2012 Right now its blowing 38-40 out of the vents and i want it as cold as i can get it. You're there. According to the factory service manual (FSM), at 90 degrees ambient temperature, the output at the dash center vent should be 37 to 48 degrees F. At 100 degrees ambient, the output should be 43 to 55 degrees F. My neighbor is an AC guy and so when he was over and i was working on it... he mentioned.. "I never seen a system that cycles like that". He's an A/C guy and he's never seen a system that cycles? I'm a car guy and I've never seen one that doesn't. It has to or it won't work. Back in the late 60s to early 70s, AMC cars (and I think GM as well, don't know much about Fords) had an adjustable cycle on the compressor. The max was a setting called "Desert." It was called that because it could only be used in hot, dry conditions, with virtually no humidity. Where I lived we had humidity. If we turned that dial all the way up to "Desert," we'd see fog blowing out the dash vents ... for about 5 minutes, right up until the evaperator froze up with a solid coating of ice on it. We have an '88 XJ, an '87 MJ, and '88 MJ, and two 2000 XJs and one 2001 XJ with A/C. They all cycle, even on MAX. Link to comment Share on other sites More sharing options...
Comanche County Posted June 17, 2012 Share Posted June 17, 2012 Every Jeep I've had with A/C cycled like that. Its all good as stated above. Link to comment Share on other sites More sharing options...
mountainman Posted June 17, 2012 Author Share Posted June 17, 2012 Thanks guys for the replies/info. Been driving it every day all over and its good. cold as a meat locker. Expansion valve hums a bit when compressor kicks in but that just seems to be an old age thing...lol. Works perfect otherwise. Link to comment Share on other sites More sharing options...
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