A/C compressor siezed
Thread Starter
|
5th Wheeling
Joined: Jan 2016
Posts: 46
Likes: 0
A/C compressor siezed
Hi,
I've got a 93' Ford Aerostar 4wd xlt. The other day my wife was driving and said she heard a terrible sound coming from the engine....noticed when she turned the AC off it stopped and was able to get it home. I've looked now, and when you turn on either the AC or defrost it looks like the AC compressor tries to run but locks up. This causes the serpentine belt to slip, the AC compressor gets super hot and actually looks to be sparking a bit....when you turn the AC/defrost back off works no prob. If this were to happen at high speed I'd foresee some serious damage to the engine occurring.
Changing the AC compressor seems relatively straightforward, but I've read you need to disconnect the refrigerant lines and cap them....wondering if this is something a home mechanic should easily and safely be able to do (and if anyone has specific instructions). Also, wondering if anyone has insight on any deeper problems that may have caused the AC compressor to seize that should be addressed first. We live in a cold climate and really don't need AC (and it didn't work very well before this issue) but defrost is essential with winter coming.
Any thoughts/suggestions are appreciated! Thanks!
I've got a 93' Ford Aerostar 4wd xlt. The other day my wife was driving and said she heard a terrible sound coming from the engine....noticed when she turned the AC off it stopped and was able to get it home. I've looked now, and when you turn on either the AC or defrost it looks like the AC compressor tries to run but locks up. This causes the serpentine belt to slip, the AC compressor gets super hot and actually looks to be sparking a bit....when you turn the AC/defrost back off works no prob. If this were to happen at high speed I'd foresee some serious damage to the engine occurring.
Changing the AC compressor seems relatively straightforward, but I've read you need to disconnect the refrigerant lines and cap them....wondering if this is something a home mechanic should easily and safely be able to do (and if anyone has specific instructions). Also, wondering if anyone has insight on any deeper problems that may have caused the AC compressor to seize that should be addressed first. We live in a cold climate and really don't need AC (and it didn't work very well before this issue) but defrost is essential with winter coming.
Any thoughts/suggestions are appreciated! Thanks!
Moderator
Joined: Aug 2002
Posts: 6,094
Likes: 379
From: Southern California
In short, yes, the home mechanic can do this...….in addition to the compressor, and give the age of the vehicle, because of particulates which have now floated through the system and could damage the new compressor, replace everything....condenser, ac accumulator, and rubber lines and of course all the O-rings.
Tuned
Joined: Nov 2011
Posts: 306
Likes: 15
If you disconnect the power to the compressor you will still have the fan for defrosting with heat only, but it will work.
Condenser coil
Accumulator
O ring kit
Compressor
And a couple orifices,, the orifice is in the evaporator, and it will most likely be clogged with metal shavings. You might need a couple because it never hurts to run it for a day and then pull it to check for crap, and put in a new one if needed.
OIL Most important!
Alot of compressors come with the oil in them,, make sure. And make sure its the proper amount.
A set of gauges and a bottle of 134a is good to.
Its fun
Condenser coil
Accumulator
O ring kit
Compressor
And a couple orifices,, the orifice is in the evaporator, and it will most likely be clogged with metal shavings. You might need a couple because it never hurts to run it for a day and then pull it to check for crap, and put in a new one if needed.
OIL Most important!
Alot of compressors come with the oil in them,, make sure. And make sure its the proper amount.
A set of gauges and a bottle of 134a is good to.
Its fun
Mountain Pass
Joined: Mar 2002
Posts: 226
Likes: 12
From: St Louis, MO
After all the components are replaced, you MUST pull a deep vacuum on the system before recharging it again. Leaving air, moisture and other contaminants in the system creates a chemical factory that will ruin all the replacement parts. Pure refrigerant is very stable and will last for years but add some oxygen to the mix and awful things start to happen and the results are a disaster. If you replace the parts yourself, take it to a shop to have it evacuated and recharged to protect your investment.
The easiest and cheapest fix for you would be separating the plug at the compressor clutch keeping it from ever engaging. The sparks and heat you saw/felt were from the clutch slipping.
The easiest and cheapest fix for you would be separating the plug at the compressor clutch keeping it from ever engaging. The sparks and heat you saw/felt were from the clutch slipping.
Thread Starter
|
5th Wheeling
Joined: Jan 2016
Posts: 46
Likes: 0
Thanks for everyone’s input! Given the age of the vehicle, cost of parts, and fact that AC isn’t really a priority for us I’m thinking disabling the compressor clutch sounds like the best option for us. Can you confirm unhooking the wiring harness pointed out in the pic attached will accomplish that? Any other fuses etc. I ought to remove as well?
Also just want to confirm this is a safe and relatively long term fix, still allowing for defrost and vent. My understanding is the compressor clutch is the Issue ....any likelihood the pulley will actually seize over time with the clutch disabled? Thanks so much y’all!
Lead Driver
Joined: Sep 2003
Posts: 7,010
Likes: 203
From: SoCal
That is the power to the AC clutch, and is the only thing you need to pull to completely disable it. Normally, the defroster will engage the AC to remove moisture from the incoming air before blowing onto your windshield. There used to be plenty of cars with no AC, so their defrosters had to work without the dehumidification. But as long as you have heat in the winter, you should still be able to defrost your windshield.
Trending Topics
Mountain Pass
Joined: Mar 2002
Posts: 226
Likes: 12
From: St Louis, MO
The a/c system's pressure switch would prevent the compressor from running in colder weather. You'd only get a little dehumidification when the temperature was more or less above freezing. Not sure where you call home but from what you say, disconnecting the clutch won't effect you much. If the windows do fog, turn on some heat to drive it away. Warm air holds a lot more moisture than cold air can.
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
10 Best Ford Truck Engines We Miss the Most!
Joe Kucinski
2026 Shelby F-150 Off-Road: Better Than a Raptor R?
Brett Foote
2027 Super Duty Carhartt Package First Look: 12 Things You NEED to Know!
Michael S. Palmer
10 Most Surprising 2026 Ford Truck Features!
Joe Kucinski
Top 10 Ford Trucks Coming to Mecum Indy 2026
Brett Foote
5 Best / 5 Worst Ford Truck Wheels of All Time
Joe Kucinski
Ford Super Duty: 5 Things Owners LOVE, 5 Things They LOATHE!
Joe Kucinski
Every 2026 Ford Truck Engine RANKED from WORST to FIRST!
Michael S. Palmer
The Best F-150 Deal of Every Trim Level (XL through Raptor)
Joe Kucinski
Moderator
Joined: Aug 2002
Posts: 6,094
Likes: 379
From: Southern California
IMHO, just in case the clutch assembly has an issue like internal bearings that can jam etc., I would remove the belt driving the AC pulley/compressor and if necessary replace with a shorter one as well as dc the ac compressor connector
FTE Community Team
Joined: Jan 2019
Posts: 10,703
Likes: 1,492
I agree with sittinguy, the guts of the compressor went bad. Sounds like the clutch is working fine. Unplug and keep driving. You'll have to replace the compressor or look for a bypass pulley later when the pulley bearings fail, but that might be a million miles from now.
Thread Starter
|
5th Wheeling
Joined: Jan 2016
Posts: 46
Likes: 0
Thanks everyone for your replies! I disconnected the compressor and things seem to be proceeding fine. I live in a cold, dry, mountainous climate so not having AC is fine and humidity is low. I always use the heater in the winter when I need to defrost the windshield. Again thanks!
Thread
Thread Starter
Forum
Replies
Last Post
894605SPD
1987 - 1996 F150 & Larger F-Series Trucks
0
Aug 23, 2008 11:01 PM
Bad Company
1999 - 2003 7.3L Power Stroke Diesel
11
Mar 28, 2005 11:36 PM