How do you tell the difference visually ( Hi pressure side and low pressure side) on a 80 240d ?

Where is the chart that gives the suggested PSI for each on a R-12 system?

going to take it in for a charge and want to know which is which..


thanks

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81' 240d 4 spd 140k on the clock

High side near front of car on line connected to condenser (in front of radiator), low side on line leading into compressor.

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'82 300SD - 361K mi - "Blue"

"Good judgement comes from experience. Experience comes from bad judgement."

listen, look, .........and duck.

just trace the hoses...the one that comes from the firewall penetration and goes to the compressor is the low side (it is the return from the evaporator) and the one that goes from the compressor to the condensor/receiver/drier is the high side. There sometimes is a "S" or "L" on the compressor on the low side (suction or low pressure) too.

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Marty D.

2013 C300 4Matic
1984 BMW 733i
2013 Lincoln MKz

Thanks

how about the suggest pressures.. is it 38 for low and 250 for high?

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81' 240d 4 spd 140k on the clock

recomended pressures are dependent on ambient tempratures. You reffer to a chart as there is no single number without knowing what temprature the measurements take place at.

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Proud owner of ....
1971 280SE W108
1979 300SD W116
1983 300D W123
1975 Ironhead Sportster chopper
1987 GMC 3/4 ton 4X4 Diesel
1989 Honda Civic (Heavily modified)
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"He who fights with monsters might take care lest he thereby become a monster. And if you gaze for long into an abyss, the abyss gazes also into you." - Friedrich Nietzsche

Ok...

The charge will be at 70*F ambient temps...

seems like there was a chart that someone posted that listed pressure temps iirc.

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81' 240d 4 spd 140k on the clock

Here is a chart from AC Kits in Arizona: http://www.ackits.com/index.cfm?fuseaction=Chart

They definitely should be knowledgable.

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Sam

84 300SD 350K+ miles ( Blue Belle )

There is not a one size fits all psi rating, but as has already be told, dependant on the ambient temp and load on the evaporator.

Look at the pictorial for some good basic hints.

http://dieselgiant.com/repairyourac.htm

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1981 300D 147k
1998 VW Jetta Tdi 320k
2001 Dodge Ram 2500 141k
1979 300D 234k (sold)
1984 300D "Astor" 262k(sold)
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