A/C Compressor Troubles

[Craig]

So I had a new A/C compressor installed 2 months ago and just replaced the low pressure switch to get it going for the summer. Unfortunately, I'm thinking it might be a lemon.

When I first started it up, it was cycling on and off every 10-15 seconds. I was thinking the charge was off. After taking the truck out on a test drive, it lessened and lessened and seems to be operating normal now. It's blowing cold and cycling normally.

The trouble is, I looked under the hood and it appears as though the back of the compressor is leaking. There's a bit of oil from the compressor that had even run down the engine block.

As well, the compressor seems to be running hot. I did a temp test and it read at 120 Celsius.

I have little experience in terms of A/C. Is this fairly normal to see when breaking in a new compressor or is it a lemon?

 

[magimerlin]

There should be "NO" oil running down the back of the a/c compressor at all... one of the o-rings is most likely done for. But will not know in till you undo the switch and or line depending on where it's coming from.

Sent from my SAMSUNG-SM-G891A using Tapatalk

 

[Craig]

There should be "NO" oil running down the back of the a/c compressor at all... one of the o-rings is most likely done for. But will not know in till you undo the switch and or line depending on where it's coming from.

Sent from my SAMSUNG-SM-G891A using Tapatalk

I figured. It should be a completely self contained system.

The shop went with a reconditioned 4seasons compressor and it started leaking in under a year. They replaced it with another and it started leaking this soon.

So it's looking like a third compressor is going in. This time, I'll buy an a/c delco compressor to go in. My father's 1976 Trans Am is still running it's original A/C compressor and it's running perfectly. Either I have terrible luck, or these compressors are just garbage.

 

[L31MaxExpress]

I figured. It should be a completely self contained system.

The shop went with a reconditioned 4seasons compressor and it started leaking in under a year. They replaced it with another and it started leaking this soon.

So it's looking like a third compressor is going in. This time, I'll buy an a/c delco compressor to go in. My father's 1976 Trans Am is still running it's original A/C compressor and it's running perfectly. Either I have terrible luck, or these compressors are just garbage.

The factory Vortec compressors are garbage. I have a sanden style Valeo compressor in the Express van I put into it back in 2006 when the original locked up at only 55K. Was hard to beat a $200 compressor kit that came with the compressor, orifice tube and accumulator.

 

[Craig]

The factory Vortec compressors are garbage. I have a sanden style Valeo compressor in the Express van I put into it back in 2006 when the original locked up at only 55K. Was hard to beat a $200 compressor kit that came with the compressor, orifice tube and accumulator.

Would I be mistaken to think that a new A/C Delco one would be a long term solution? I like to use oem parts whenever but would be willing to look at other brands if they're proven better.

I've been warned of recondition compressors before but just went with what the warranty covered. 4seasons seems to have mixed reviews.

 

[L31MaxExpress]

Would I be mistaken to think that a new A/C Delco one would be a long term solution? I like to use oem parts whenever but would be willing to look at other brands if they're proven better.

I've been warned of recondition compressors before but just went with what the warranty covered. 4seasons seems to have mixed reviews.

I personally have not had good luck with them. I also saw a ton of them fail working in an aftermarket shop back in 2005 to 2006 time frame. Almost every GMT400 based system I have worked with developed a leak at the case o'ring. Vehicles with dual air seemed more failure prone but they all seemed to fail in that method. Sometimes they would also run low on oil and seize.

I put dozens of Valeo compressors in Express vans, Astro/Safari Vans, S10s and GMT400 trucks and SUVs. Never ran across a dud out of the box and they cooled well.

There is now an actual Sanden floating around as well. It is a 7 piston model that operates more smoothly than the 6 cylinder models.

The Valeo in my Express is from 2006, has over 70K on it, lots of idle & stop and go and still going strong. Considering we use a/c about 8 months out of the year and most of my mileage is put on it during the summer months, it has held up well.

 

[Craig]

I personally have not had good luck with them. I also saw a ton of them fail working in an aftermarket shop back in 2005 to 2006 time frame. Almost every GMT400 based system I have worked with developed a leak at the case o'ring. Vehicles with dual air seemed more failure prone but they all seemed to fail in that method. Sometimes they would also run low on oil and seize.

I put dozens of Valeo compressors in Express vans, Astro/Safari Vans, S10s and GMT400 trucks and SUVs. Never ran across a dud out of the box and they cooled well.

There is now an actual Sanden floating around as well. It is a 7 piston model that operates more smoothly than the 6 cylinder models.

The Valeo in my Express is from 2006, has over 70K on it, lots of idle & stop and go and still going strong. Considering we use a/c about 8 months out of the year and most of my mileage is put on it during the summer months, it has held up well.

I'll have to drop it by the shop. On closer inspection, it might just be the o-rings that are leaking. If it does need a new compressor, I'll ask what other brands will work with it. I know some conversions don't work with the TBI.

As well, when I replaced the low pressure switch and it's pigtail connector, I noticed one of the two wires on the pigtail connector was marked. I was told by a retired mechanic that it was a circuit and it didn't matter which wire matched up to which. Just want to confirm this if anyone knows.

 

[Darrell]

Agree..sounds like an o-ring is bad where the pressure lines bolt to the back of compressor. Also if one "cranks" down on the bolts that run thru the compressor for the brackets..well that can shift the casing and you'll see some signs of leakage along the edges.

If you have a good shop they should be adding pag oil with dye to the system. The dye has a neon yellow/greenish appearance to it. If the system ever fails again, you'll see exactly where the leak is coming from using a purple light in the dark.

I've seen all compressors go bad. Factory, delco replacements as well as other brands new or rebuilt. It can simply come down to the installer and did they put enough oil in the system as well as to much oil in the system. Did they over tighten the bracket bolts or pinch an o-ring on the pressure lines.

Are you a DIYer ? If so, a/c work not that hard to do and learn

 

[Craig]

Agree..sounds like an o-ring is bad where the pressure lines bolt to the back of compressor. Also if one "cranks" down on the bolts that run thru the compressor for the brackets..well that can shift the casing and you'll see some signs of leakage along the edges.

If you have a good shop they should be adding pag oil with dye to the system. The dye has a neon yellow/greenish appearance to it. If the system ever fails again, you'll see exactly where the leak is coming from using a purple light in the dark.

I've seen all compressors go bad. Factory, delco replacements as well as other brands new or rebuilt. It can simply come down to the installer and did they put enough oil in the system as well as to much oil in the system. Did they over tighten the bracket bolts or pinch an o-ring on the pressure lines.

Are you a DIYer ? If so, a/c work not that hard to do and learn

The previous owner went through a shop to have everything done that was needed and the compressor started leaking while he owned it, but he never took it in. So after I bought it and took it in, the shop agreed to do a second-hand warranty on the work and replaced the compressor / high pressure switch with this one. The shop initially charged $2000CAD after tax just to do compressor, high pressure switch, drier/receiver, orifice tube, ac gasket and a recharge. And another $300CAD from me when I brought it in for warranty work and a clamping diode / diagnostics was not included. And that price is with a 4seasons compressor. I went and replaced the low pressure switch and it's pigtail connector myself because they had quoted $265 to do that, with non-ac-delco parts.

It seems like a complete rip off, but I can't really complain given the situation of the warranty.

I've never done AC work before, it's actually my first vehicle with AC. I've always driven around old, plain jane vehicles. I helped a buddy but a compressor in his old truck about 5 years ago but will definitely be doing it myself with some help from more knowledgeable friends if it goes after the warranty.

The oil is dyed. I thought it was coolant at first but traced it up to the compressor.