I think my a/c compressor needs replaced

[thedrewski2016]

hey guys, i'm at the end of my knowledge & search abilities here. my clutch won't engage. i knew enough to check fuses & relays. fuses test good, swapped relay with my fog lights, still no clutch & fogs still work. with the help of users here i started going further. i got to no power on my compressor harness, but never checked it for ground. ford tsb 19091 issue....but got that line repaired & clutch kicked in briefly, by that i mean i had that frigid air fords are known for a few moments i ran it. tried it the next day after work, nada....plain nearly hot air. this evening i checked the harness again, both ground & hot are working with a light tool (red/green led test tool) not a volt meter to check the actual voltage going. but some is. i know this isn't very detailed but that's as far as i can tell. i rented vacuum pump from autozone & it held a vacuum for about 45 minutes while i did some weed eating (i have a.d.d. & seem to have to multitask everything). other things i had checked, blend actuator works fine visually checked as well as vent/recirculate door (checked behind glove box [also found my glove box DOES have a light, & replaced it also] to see them move). i have jumpered individually & separately both high & low pressure switches, still no clutch (even though it spins freely)

vehicle info : 2005 mountaineer premier /w rear climate & the eatc (no knobs, digital buttons), before pulling a vacuum i had a static pressure of 51 on a 84ish degree F day.

any help would be greatly appreciated before i cave & take it to a garage. you all wonderful people have helped me come this far (& prevented a potential no crank issue as my red wire was rubbed a bit too by that oil drip pan, smdh ford) so i'm hoping you all can help me the rest of the way. i'm no mechanic (comp sci major) but i can follow instruction pretty well i think.

so, what do you all think?

ps - if this needs in the hvac section, sorry mods, please move it.

 

[Joe in NY]

51 psi on an 84* day means that system was near empty, just gas and no liquid anywhere. So you have a leak somewhere. Also did you try recharging after you pulled a vacuum? If it isn't holding vacuum then that means you are pulling moisture in and that wont help the system. Might need to have a shop leak search it. But first look for oily spots on the condenser, lines, receiver, and bottom of compressor.

 

[thedrewski2016]

Thanks Joe, I started to after the vacuum held for about 30 minutes while I was weedeating. I added one 12oz can. But my clutch on the compressor still never kicked in. So then I jumped my low pressure switch, still nothing, then the high also, still never engaged, while I added a 2nd can. What am I missing?

Added another can, still no clutch engaging. Lowside is now 95psi....suggestions?

 

[Big Z]

Try tapping the hub face of your a/c clutch with a long screwdriver while the engine is on and the a/c switch is on (careful..just a quick tap).
If the compressor is getting power (it is now, right?) and the air gap on the clutch is too large for the magnet to overcome, it can cause failure to engage. If you tap it and it engages, you pretty much know you have a compressor clutch issue. Sometimes there are spacers (thin washers) behind the hub face. Remove 1 spacer and you may be back in business on the cheap.

 

[thedrewski2016]

Thanks Big, forgot to meantion ife tried that with he handle side of a tack hammer. But I double checked with my large flathead....no dice. Engine running, 60° a/c on fan maxed.....didn't engage. I feel like maybe when I was diagnosing that 19091 issue & it kicked on, might it have killed the magnet? I do for sure have power don't on the harner now, enough to power a test light. I found a new 9v I'm going to test it with that in a few. I'll edit with results.
Edit - I see no air gap also....but it does still sosp freely as of last time under the hood. Day before yesterday .

 

[Big Z]

Have you tried running a hot wire directly from the battery to the compressor clutch? You should be able to do that with the engine off.

 

[ptf18]

Thanks Joe, I started to after the vacuum held for about 30 minutes while I was weedeating. I added one 12oz can. But my clutch on the compressor still never kicked in. So then I jumped my low pressure switch, still nothing, then the high also, still never engaged, while I added a 2nd can. What am I missing?

Added another can, still no clutch engaging. Lowside is now 95psi....suggestions?

The system (Im not certain) only "holds" 2ish pounds of Freon. I wouldn't think you could have put in a 2nd container (12oz) of Additional Freon without the compressor running (clutch engaged). If you had vacuum (30ish Hg)before you refilled the system, I could see that you would have got one can of Freon into the system but then the system would be close to "static" pressure (maybe 60psi???) . Even though the 2nd can is "pressurized" higher than the "static" pressure of the partially filled system, I wouldn't thonk you would have got much of the 2nd container into the system.

Regardless. What is your current "static" pressure? I see that you mention "Lowside is now 95psi"..... that should also be the same on the High side....although it will be hard to read on the gauge.... whats the High side?

 

[Big Z]

Temperature can change the static pressure easily and even dramatically. It's not a very useful measurement besides finding a very low charge (like the 50psi on an 85 degree day where it should be ~95psi). Low and high side static pressures will surely have equalized. A flow restriction will just cause the equalization to happen more slowly..still, minutes rather than the days that this hasn't had the compressor engaging. Compressor doesn't need to run to get a full charge, and it can actually be done pretty quickly on cars by feeding liquid.

 

[thedrewski2016]

Sorry guys, been busy with family court. The "mom" is still trying to act like she's putting up a fight. I'd like to thank you guys again for all the help so far. Anywho.

When I said lowsidewas 95 I should've been clearer. It was a static pressure. Sofar I have out about 2.5 cans since evacuating & testing vacuum. I do have rear air which the sticker says I'll need 4.67 (12oz) cans. Is that correct?

Also, no I haven't tested direct 12v to clutch yet but intend to this evening. Gave her a bath yesterday to get back into it. Also need to upgrade my factory sub & am with this mbQuart pair I've had since March .

Thanks again people, I really appreciate all the help & knowledge shared here.

 

[Big Z]

Is there enough room for you to get an ohm reading across the coil wires?

 

[thedrewski2016]

I have no meter but I could acquire one. You mean from the terminals on the clutch magnet, not the harness that powers it correct?

 

[Big Z]

Yeah. There should be some resistance.

 

[TechGuru]

Everyone should at least have one of these meters...

7 Function Digital Multimeter

 

[thedrewski2016]

I wish our harbor freight was open already, but theure still finishing the building. Anyway, picked up a meter from Walmart today, will post results soon as I can get them after work.