With springtime in the South East US comes the dreaded double "H" (Heat and Humidity)

Turned on the AC in the 87 300D, worked really well for about 15 minutes and then a lot of mist came out of thet vents, followd by warm air.

The ACC unit had failed, causing the compressor to not cycle, which blew out the front seal on the compressor and blew out the evaporator in the heater box inside the car.

I saw the evaporator after the dash had been removed, and the whole lower side had been peeled back.

Total damage to the wallet was $4400.00, which was for all new AC components (compressor, receiver/dryer, evaporator, etc), a new ACC unit, and labor. I also had the tech replace all the vacumn servos and all the vacumn lines along with all the little light bulbs since the dash was already out

The thing that I saw when the dash was out, was that there is a very hefty tubular brace that runs from one side of the car to the other. This has to be a major part of the "safety cage" for this car.

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Chris Young

Current cars:
1978 240D 4-spd manual 99k miles
1987 300TD - 132k miles
1987 300SDL - 280k miles.
1996 Subaru Outback - 132k miles
2003 Chevy Silverado Duramax/Allison - 195k miles

"My wife thinks I have a disease..... I think I have just inhaled too much diesel exhaust .... My neighbors think, well, who cares what the neighbors think"

Sounds like an expensive failure.
It is also possible that the system was contaminated with moisture, I understand that moisture in an R-12 system can cause overpressurization, had it been "charged" lately?

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Gone to the dark side

- Jeff

Ouch! I paid $1600 more for the whole car. I have a high "sphinchter factor" on my working, yet none too cold, AC. Wouldnt part with the dough, I'd wait until winter and R&R the components myself...like all winter long

Really debating on whether I want to fully charge the system or not. Fresh lube would be good, but I'm thinking of taking it to a tech at the MBz garage, with some experience, so he charges it "just enough".

Oh well, you'll be chillin' in that ride now!

No, the system had not been touched at all.

I was really surprised that there is not a "overload" circuit on these units. I seem to remember my old Chevrolet cars having a pressure cut out switch on the high-side to protect the system for this type of failure.

__________________
Chris Young

Current cars:
1978 240D 4-spd manual 99k miles
1987 300TD - 132k miles
1987 300SDL - 280k miles.
1996 Subaru Outback - 132k miles
2003 Chevy Silverado Duramax/Allison - 195k miles

"My wife thinks I have a disease..... I think I have just inhaled too much diesel exhaust .... My neighbors think, well, who cares what the neighbors think"

Anything to keep the better half happy, since it is her car. I am too well fed to not keep her happy.

I think you could hang meat in the car now. It is almost too cold (notice that I said almost.....)

__________________
Chris Young

Current cars:
1978 240D 4-spd manual 99k miles
1987 300TD - 132k miles
1987 300SDL - 280k miles.
1996 Subaru Outback - 132k miles
2003 Chevy Silverado Duramax/Allison - 195k miles

"My wife thinks I have a disease..... I think I have just inhaled too much diesel exhaust .... My neighbors think, well, who cares what the neighbors think"

Ouch, I assume a major part of the cost was the labor to replace the evaporator. I've blown up my system a couple of times (without hurting the evaporator) and got it all put back together for less than $1500. These systems seem to eat themselves about once per 100K miles, but I think the evaporator failure is unusual.

Your car has safety switches for both high and low pressure conditions. The sensor was defective or somebody bypassed it.