Wrenches to open the fittings to replace the o-rings, and if the old
compressor generated any slop ("gray death" -- residue that looks
like aluminum paint in the high pressure lines) you will need to pull
the hose set and have a filter installed in the suction line to
protect the new one, plus some sort of mechanism for flushing the
condenser and if you can the evaporator (although you must remove the
expansion valve to do this, and it's a pain in the W126, I think).
You MUST have the gauge set, as it is absolutely imperative that you
actually achieve the correct vacuum and can verify that it holds
indefinitely.
Low pressure side will be between 40 and 50 psi at 1500 rpm fully
charged while the high side will vary depending on air temp -- at 70
F mine was 225 psi once I had liquid showing in the sight glass, even
as foam, and stayed there as I added the remainder of the freon. I
put in enough to show only liquid in the sight glass, then a bit for
reserve against the inevitable slow leaks. Note that since you will
be adding PAG 46 (or PAG 52 if you can find it) the liquid will be
cloudy, not clear due to suspended residual mineral oil. Once the
foam disappears you are essentially charged to cooling capacity.
The gauges will tell you whether or not things are actually working
correctly, I'd not charge a dry system without them, and am really
unwilling to charge without them at all.
Peter
On Jul 27, 2008, at 8:38 PM, Luther wrote:
> I will be replacing my SDL's a/c compressor soon. I already have a
> high volume
> vacuum pump capable of 30". What else do I need? Do I absolutely
> need a set
> of pressure gauges? I just topped off Dad's TD and my coupe with a
> can of
> freon from Wal-Mart that has a pressure gauge built in. Is this
> enough?
>
> What pressure do you fill to when you do not fill by weight? 25psi
> is the low
> end of the blue "filled" area of the pressure gauge and I assume I
> can have
> higher pressure than 25psi? TIA all,
>
> Luther KB5QHU Alma, Ark
> '87 300SDL (278,xxx mi)
> '85 Ford F250 6.9 diesel (x59,xxx mi) BioBeast
> '82 300CD (181 kmi)
> '82 300D (74 kmi) getting donor engine-sold
> '85 300D (280,176) parts car sans engine "The Accordion"
>
> _______________________________________
> http://www.okiebenz.com
> For new parts see official list sponsor: http://www.buymbparts.com/
> For used parts email [EMAIL PROTECTED]
>
> To Unsubscribe or change delivery options go to:
> http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
_______________________________________
http://www.okiebenz.com
For new parts see official list sponsor: http://www.buymbparts.com/
For used parts email [EMAIL PROTECTED]
To Unsubscribe or change delivery options go to:
http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
