2000 C5 Explosion Under Hood

hvymtlc5 · Post by **hvymtlc5** » 31 Aug 2014, 18:44

Routine trip to town - massive explosion under hood. Sounded like tire blowing (car next to us pulled over). Made a quick inspection and saw nothing. Wife notice AC was no longer blowing. Checked compressor - sure enough the clutch was still working (thankfully it didn't freeze up and shred the belt), but the compressor was not. Assuming compressor exploded (no oil or freon anywhere). In all my years of cars have never heard of the compressor blowing up internally....

Is the compressor hard to get to?

Post by **abscate** » 31 Aug 2014, 19:19

It is an awkward replacement but not so bad it's worth paying some 100 USd per hour to do.

Post by **kahl** » 31 Aug 2014, 19:23

It really depends on your definition of hard. I got to my compressor by unbolting the power steering pump then laying on top of the engine. Next I removed the alternater. This opened up a way to remove the compressor. The two lines are held on by 7mm hex bolts.

Make a diagram of your serpentine belt before removing. if you do not have your A/C system vacated the R-134 will vent into the atmosphere.

Post by **polskamafia mjl** » 31 Aug 2014, 20:16

If you decide to do the repair please have the system evacuated professionally. There's no reason to vent that stuff into the atmosphere.

Post by **Ozark Lee** » 31 Aug 2014, 21:03

I actually doubt that the compressor itself exploded. The typical failure mode for the compressor is for it to grenade internally but the only sound you typically hear is the squeal of the serpentine belt as the compressor internally seizes. Since you described a sound like an explosion my guess is that either it blew a line, the condenser coil blew up or perhaps the accumulator blew up. The compressor clutch will continue to spin freely and the low pressure cutout switch will turn the compressor clutch off but the compressor will not actually be turning.

If you can get a pressure gauge on the system it will get you pointed in the right direction. If the system still has pressure then it may well be the compressor, if you have no pressure then there was a massive failure in the sealed system. The latter scenario is your cheaper and easier fix since it will simply mean a replacement of the failed part and a new accumulator. Even if the accumulator didn't blow it is a good practice to replace it any time the system has been open for more than a few minutes. There is a desiccant in the accumulator that removes moisture from the system and it will absorb humidity.

When a compressor fails it typically a messy event and debris from the internals of the compressor get distributed throughout the system. The way the condenser is built it can't really be flushed and it should be replaced, along with the orifice tube and the accumulator. The rest of the system needs to be flushed with a refrigeration specific flushing fluid. The process of flushing the system is fairly expensive and it isn't totally effective, there will be residual metal shavings remaining in the system even after it is flushed and those contaminates increase the likelihood of another compressor failure.

As far as R-134A goes you, as a car owner (As of this posting) can vent it without fear of going to EPA jail. A professional, working for hire, cannot legally vent it to the atmosphere though. R-134A is an HFC refrigerant which has no Chlorine and thus it poses no harm to the Ozone layer. If for no other reason than the cost of the refrigerant it is never advisable to vent it though.

...Lee

Post by **jblackburn** » 31 Aug 2014, 21:42

It's not uncommon for rocks to take out the condensor at the front of the car - especially if you're missing the splash shield at the bottom of the car like 50% of these old Volvos are. Boom, freon everywhere!

Post by **JimBee** » 31 Aug 2014, 21:46

EDIT: While I was crafting this piece, Ozark Lee posted. Hopefully, as he said, it's not the compressor. I was going to mention that after I had the shop replace my dryer/accumulator, they handed me the key and jovially said, "Good to go". I started the engine, drove two feet and thought I'd blown a tire — just like you described. It was the spring-lock connector that wasn't properly seated when they replaced it and it blew apart. There was oil and refrigerant all over that area. They redid it and it has been fine.

SO, I leave my post. You might find it helpful if you're going to replace the compressor.

+1 on having it evacuated, if there's any pressure remaining, which their might not be since you heard it blow out.
Also, agree on pulling the alternator and power steering pump.

I recently pulled a compressor from a pick 'n pull. Access to the mount bolts is a little tricky.

I removed the cooling fan to get more room to swing a long bar to break the mount bolts and get some travel on my ratchet. If the bolts aren't too rusty the fan comes out in 10 minutes, max. PROTECT your radiator with the fan out. Heavy corrugated would work.

I still couldn't get my ratchet and socket on the top inner-side mount bolt due to the dip stick tube being in the way, just barely, but it had to come out, which is pretty easy. Just stuff something in the hole until you're done.

Working through the fender flap "window" I was able to break the lower mount bolt on that side with a smaller 3/8" breaker bar with short pipe extension, then got a ratchet spanner on it and with short strokes finally got that one out. The mount bolts are pretty tight. I think the mount bolts are 17 mm.

I tried to remove a compressor once before and couldn't crack the size 40 Torx screw that holds the dryer hose out of the compressor with the compressor still installed. Unless you're removing the dryer, too, which you might want to do if it's very rusty, you'll need to remove the Torx screw for that hose. On the junk yard car I loosened the compressor first, so I could get a better angle on the Torx screw, then removed the Torx screw. I recommend that approach, though best to have a helper to hold the compressor when you do it so you don't damage your radiator.

I'm sure you're aware, there are two pressure lines on the back of the compressor. I didn't try to remove the lower one (Torx screw) because it's harder to get to and I didn't want to risk stripping it. Instead, you can leave that line on the compressor and remove the other end of it from the condenser. That screw is easy to get to.

If you're planning to change the dryer, I suggest when you have the system evacuated, pay the tech something (if necessary) to open the spring lock connector on the dryer tube.That one defeated me on my car and I had to have it done in the shop. If you remove the screw on the dryer tank mount bracket and the one on the band clamp before taking it to the shop, a tech would just need to put their expensive tool on that connector and probably get it loose easily then pull the tubes apart.

If you go that route, you might be able to remove the compressor with the dryer tank and hose still connected. Then you can put the whole assembly on a flat surface and work on the Torx bolts by tapping the bit to seat it, etc., as well as the dryer to hose connection which is tough to do in the car.

I think I sourced my new dryer tank from AutohausAZ for about $25.00 a year ago. Plus you need a couple of o-rings for it for the tube connection and one for the compressor connection.

Removing the compressor took me a couple of hours. I have a pretty good tool set. That Harbor Freight ratchet spanner that's been kicking around in my tool bag unused for a year got a workout on this project. It's doable.

hvymtlc5 · Post by **hvymtlc5** » 01 Sep 2014, 05:17

Thanks all for the suggestions - I'll take a better look this morning. I didn't see any debris or oil yesterday so I'll look at the other things mentioned.

Post by **abscate** » 01 Sep 2014, 05:20

I did my 1999 evap core and replaced the dryer and both metal hoses as well as the condensor hoses. I did all the disconnects on the car working underneath. Use good quality, sharp Torx and hex tools on these bolts, not Harbor freight stuff, and make sure they are seated well. Clean road dirt out with a dental pick first so the tool but goes all the way in. Make sure you apply pure torque to the fasteners..it's easy to start lifting when they are tight.

After you affix the gater sprung tool, you can apply twisting torque to the AC lines with a vice grip to break them free.

hvymtlc5 · Post by **hvymtlc5** » 01 Sep 2014, 08:32

Well the hose blew that connects to the back of the compressor. It broke at the junction where the steel is crimped to the rubber. Does this go to the accumulator or the condenser. Can I just replace the hose (have not crawled under to take a look yet).

How much freon does the car hold and should I need to add more oil?

Thanks for all the superb help!