AC locked up this summer, do I need to flush - The 1947 - Present Chevrolet & GMC Truck Message Board Network

phlegm · 09-29-2006, 09:34 AM

My compressor locked up this summer, I thought the clutch hub went bad but when I replaced it it ended up being the entire unit. Do I need to do a complete flush of the system before closing it up with a new compressor and charging? I am wondering about any metal that may have been discharged when it locked up.

cdowns · 09-29-2006, 10:39 AM

since it going to be apart and open i'd say do a system flush b-4 recharging

70rs/ss · 09-29-2006, 12:05 PM

Yeah, if there is any chance the aluminum shavings from the pistons locking up got into the system, it is just piece of mind to flush and be sure. They usually push metal around be fore they finally to the death lock.

69rut · 09-29-2006, 02:31 PM

You might want to replace the dryer also. I think they act as filters.

phlegm · 09-29-2006, 03:08 PM

How much $$ can I expect on this? I am thinking of getting the dryer and Compressor and mounting htem myself before taking it to the AC guy to flush. Then shoud I add the coolant and oil myself on a backyard job or have the mech do it since he is standing right there.

Aarons72s · 09-29-2006, 03:36 PM

Compressors usually run about $100 to $200 depending on where you get them. You should be able to get one from any parts house. The dryers usally run about 55 dollars. Hope this helps.

phlegm · 09-29-2006, 03:44 PM

How about a flush? any idea how much those run. I also am a little nervous about charging the system myslef but from what I can gather its not that big a deal with the new coolant, and the guages come on the bottles now from what I see .... or am I an idiot? please be honest I have thick skin lol.

jsbgump · 09-29-2006, 03:52 PM

I would flush the a/c system anytime it has a compressor failure

**john** · 09-29-2006, 04:41 PM

What I did was pull the condenser and all the lines and flush them out of the truck. Always use a new dryer when there has been a problem or it has been open to atmosphere for a time. You can buy A/C flush at parts house. With the condenser out you can flush it easily several times to get all the junk out. I guess the dryer should catch all the metal. Mine has been 8 yrs now with no probs.

**clay68c10** · 09-29-2006, 06:17 PM

Any restriction in the system can hold the aluminum debris. At work we replace the dryer and expansion valve, separate the easy to access connections and flush ALL of it. If it were my stuff, I'd try to clean out the e-valve and reuse it. I guess you should clean out the POA valve too. With both of those off the evap, it will be easy to flush it out.
You could call that overly cautious, but at work if it shells again we do it the second time for free...

Aarons72s · 09-29-2006, 08:50 PM

The only hard part is putting a vacum on the system. I think most shops will do it for a nominal fee. Just remember to replace the o rings at every junction you open.

project1971 · 09-29-2006, 09:21 PM

Yes you should flush the system when it shells. You can flush it yourself if you have an air compressor. You also need to replace the orfice valve, just a few dollers but when the compressor shells this is the first place any metal goes. To flush the system get a can or two of brake cleaner, spray the brake cleaner in the high side line from the compressor, and then stick a rubber tip air gun in the line and a rag on the other open in to catch all the crap being blown out. Do this several times until nothing else comes out. I do this on everyone I do and have yet to have one come back, 16 years now. Just remember to keep the air blowing through a little while to get everything out. If compressor shells you need to replace the compressor,dryer, and orfice. You should be able to clean everything else, it in doubt about metal in it, replace it. Hope this helps

BLACK AND BLUE 67-72 · 10-01-2006, 01:18 PM

Yes you must flush the system, especially if you want to have any warranty on the compressor, they require you to flush, install new receiver/drier, orfice tube or POA/ expansion valve anytime you install a new compressor. And usually you have have to have proof that it was flushed, like a bill from an auto repair shop showing a system flush.

phlegm · 10-06-2006, 02:38 PM

is the POA and the orfice valve the same thing?

BLACK AND BLUE 67-72 · 10-06-2006, 05:47 PM

Expansion valve or orfice whichever it has, usually expansion on older trucks.

09-29-2006, 09:34 AM	#1
phlegm Still Green but learning Join Date: Nov 2004 Location: Central NC Posts: 1,895	AC locked up this summer, do I need to flush My compressor locked up this summer, I thought the clutch hub went bad but when I replaced it it ended up being the entire unit. Do I need to do a complete flush of the system before closing it up with a new compressor and charging? I am wondering about any metal that may have been discharged when it locked up. __________________ -- Cory 71 Cheyenne 10 - SWB, 350, "3 on the tree" AC cab 07 Suburban LTZ 4x4 2010 Acura TL 98 Mastercraft "FrankenStar" 225 27253 UPS/USPS IIOY....nope never was

09-29-2006, 10:39 AM	#2
cdowns Senior Member Join Date: Jan 2003 Location: daytonabeach Posts: 22,956	Re: AC locked up this summer, do I need to flush since it going to be apart and open i'd say do a system flush b-4 recharging __________________ 71c-10 350/2004r/4:11 lowered3/4 longbed/dead by hurricane MEANING OF DEATH::::: SOMEBODY ELSE GETS YOUR STUFF DONT BELIEVE EVERYTHING YOU THINK TAKE MY ADVISE;I DON'T USE IT ANYWAY

09-29-2006, 12:05 PM	#3
70rs/ss Registered User Join Date: Dec 2004 Location: Northern AZ Posts: 7,271	Re: AC locked up this summer, do I need to flush Yeah, if there is any chance the aluminum shavings from the pistons locking up got into the system, it is just piece of mind to flush and be sure. They usually push metal around be fore they finally to the death lock.

09-29-2006, 02:31 PM	#4
69rut Registered User Join Date: Sep 2006 Location: SE Virginia Posts: 158	Re: AC locked up this summer, do I need to flush You might want to replace the dryer also. I think they act as filters. __________________ trailers are for boats

09-29-2006, 03:08 PM	#5
phlegm Still Green but learning Join Date: Nov 2004 Location: Central NC Posts: 1,895	Re: AC locked up this summer, do I need to flush How much $$ can I expect on this? I am thinking of getting the dryer and Compressor and mounting htem myself before taking it to the AC guy to flush. Then shoud I add the coolant and oil myself on a backyard job or have the mech do it since he is standing right there. __________________ -- Cory 71 Cheyenne 10 - SWB, 350, "3 on the tree" AC cab 07 Suburban LTZ 4x4 2010 Acura TL 98 Mastercraft "FrankenStar" 225 27253 UPS/USPS IIOY....nope never was

09-29-2006, 03:36 PM	#6
Aarons72s Registered User Join Date: Apr 2006 Location: oklahoma Posts: 10,670	Re: AC locked up this summer, do I need to flush Compressors usually run about $100 to $200 depending on where you get them. You should be able to get one from any parts house. The dryers usally run about 55 dollars. Hope this helps.

09-29-2006, 03:44 PM	#7
phlegm Still Green but learning Join Date: Nov 2004 Location: Central NC Posts: 1,895	Re: AC locked up this summer, do I need to flush How about a flush? any idea how much those run. I also am a little nervous about charging the system myslef but from what I can gather its not that big a deal with the new coolant, and the guages come on the bottles now from what I see .... or am I an idiot? please be honest I have thick skin lol. __________________ -- Cory 71 Cheyenne 10 - SWB, 350, "3 on the tree" AC cab 07 Suburban LTZ 4x4 2010 Acura TL 98 Mastercraft "FrankenStar" 225 27253 UPS/USPS IIOY....nope never was

09-29-2006, 03:52 PM	#8
jsbgump Gone Fishing Join Date: Aug 2005 Location: Fort Worth, Texas 76135 Posts: 12,361	Re: AC locked up this summer, do I need to flush I would flush the a/c system anytime it has a compressor failure __________________ 68 Chevy Short Fleetside LSX Swap Under Way 3.73 posi 2.5/4 drop Frame of resto has been started 2022 Hyundai Tucson Limited 2019 Chevy Traverse Redline Edition Wifes Ride Build Thread http://67-72chevytrucks.com/vboard/s...=1#post3483616

09-29-2006, 04:41 PM	#9
john member #16 Join Date: Dec 1999 Location: Yuba City Ca. Posts: 3,618	Re: AC locked up this summer, do I need to flush What I did was pull the condenser and all the lines and flush them out of the truck. Always use a new dryer when there has been a problem or it has been open to atmosphere for a time. You can buy A/C flush at parts house. With the condenser out you can flush it easily several times to get all the junk out. I guess the dryer should catch all the metal. Mine has been 8 yrs now with no probs. __________________ john http://67-72chevytrucks.com/vboard/showgroups.php board vendors http://www.flickr.com/photos/1745471...7602865984234/

09-29-2006, 06:17 PM	#10
clay68c10 Senior Member Join Date: Aug 2004 Location: Centennial, CO Posts: 2,979	Re: AC locked up this summer, do I need to flush Any restriction in the system can hold the aluminum debris. At work we replace the dryer and expansion valve, separate the easy to access connections and flush ALL of it. If it were my stuff, I'd try to clean out the e-valve and reuse it. I guess you should clean out the POA valve too. With both of those off the evap, it will be easy to flush it out. You could call that overly cautious, but at work if it shells again we do it the second time for free... __________________ ClusterTruck: 68 C10 Bought in 89, wrecked in 03. Slow low $ rebuild started '17. 6.0 & TKO http://67-72chevytrucks.com/vboard/s...d.php?t=788602 93 K1500 Short Step, 350, NV4500, EBL flash ECU. Vortec heads & roller cam someday... 05 Jeep Wrangler Unlimited. 3” lift & 6-speed 02 E320 the insurance total “free car” 13 Tahoe LTZ

09-29-2006, 08:50 PM	#11
Aarons72s Registered User Join Date: Apr 2006 Location: oklahoma Posts: 10,670	Re: AC locked up this summer, do I need to flush The only hard part is putting a vacum on the system. I think most shops will do it for a nominal fee. Just remember to replace the o rings at every junction you open. Last edited by Aarons72s; 09-29-2006 at 08:50 PM.

09-29-2006, 09:21 PM	#12
project1971 Registered User Join Date: Apr 2003 Location: Oklahoma City Posts: 605	Re: AC locked up this summer, do I need to flush Yes you should flush the system when it shells. You can flush it yourself if you have an air compressor. You also need to replace the orfice valve, just a few dollers but when the compressor shells this is the first place any metal goes. To flush the system get a can or two of brake cleaner, spray the brake cleaner in the high side line from the compressor, and then stick a rubber tip air gun in the line and a rag on the other open in to catch all the crap being blown out. Do this several times until nothing else comes out. I do this on everyone I do and have yet to have one come back, 16 years now. Just remember to keep the air blowing through a little while to get everything out. If compressor shells you need to replace the compressor,dryer, and orfice. You should be able to clean everything else, it in doubt about metal in it, replace it. Hope this helps __________________ 2008 Ford FX2 Screw 1971 C10 project in shop now! 2004 Pontiac Grandam (wifes) 2000 Cavalier z24 (gas saver)

10-01-2006, 01:18 PM	#13
BLACK AND BLUE 67-72 Firefighter Join Date: Feb 2001 Location: Yellville, Ar, USA Posts: 1,943	Re: AC locked up this summer, do I need to flush Yes you must flush the system, especially if you want to have any warranty on the compressor, they require you to flush, install new receiver/drier, orfice tube or POA/ expansion valve anytime you install a new compressor. And usually you have have to have proof that it was flushed, like a bill from an auto repair shop showing a system flush. __________________ '72 Chevy SWB 350 Auto '67 GMC LWB 350 4 speed '70 Chevy 4x4 Stepside 350 Auto Yellville, Ar. USA Last edited by BLACK AND BLUE 67-72; 10-06-2006 at 05:47 PM.

10-06-2006, 02:38 PM	#14
phlegm Still Green but learning Join Date: Nov 2004 Location: Central NC Posts: 1,895	Re: AC locked up this summer, do I need to flush is the POA and the orfice valve the same thing? __________________ -- Cory 71 Cheyenne 10 - SWB, 350, "3 on the tree" AC cab 07 Suburban LTZ 4x4 2010 Acura TL 98 Mastercraft "FrankenStar" 225 27253 UPS/USPS IIOY....nope never was

10-06-2006, 05:47 PM	#15
BLACK AND BLUE 67-72 Firefighter Join Date: Feb 2001 Location: Yellville, Ar, USA Posts: 1,943	Re: AC locked up this summer, do I need to flush Expansion valve or orfice whichever it has, usually expansion on older trucks. __________________ '72 Chevy SWB 350 Auto '67 GMC LWB 350 4 speed '70 Chevy 4x4 Stepside 350 Auto Yellville, Ar. USA



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