Volvo 850 How to add oil to new a/c compressor

[JimBee]

abscate: kind of you to offer! I'm in Minneapolis, so that might not be practical. Harbor freight actually has 2 stores in this area. I hadn't considered buying the equipment, but I have 2 '96 850 systems that need work and recharging, so I'll look into that. Thanks for the suggestion.

It occurs to me that the local Autozone has that equipment available to rent. But how hard is it to do the whole procedure correctly?

[abscate]

With the manifolds and vacuum pump its really easy. I did two this morning. SWMBO BMW only had 25F of temperature differential and I suspected it was low level. I pumped it down this morning, let it sit for 6 hours with no change, then charged to spec.

Now blowing 40F of differential.





It is much easier and cheaper to check for leakage with vacuum than with R134A , not to mention the green factor.

[JimBee]

The gauges and (OEM Tools) pump is available for rental nearby so I have access to those.

Are all the steps in this video consistent with how MVS a/c aces are doing it? I have read and a Volvo buddy told me that you should not shake the refrigerant can upside down when recharging, but rather just meter in very small amounts as many times as needed to reach max.

[abscate]

The danger is you can add liquid to the compressor, which is bad.

I really like the concept of recovering from zero charge and then adding the correct charge by mass. It removes the uncertainties completely as well as drying your system out totally , if you pump on it for a couple hours.

You just measure the mass of the cans, and let the system slowly take the charge until it's right then stop. Typically our cars take 750g which is an annoying 2 1/4 cans but you hot weather guys can undercharge slightly for better cooling and try. Just 2 cans at 680g. You can buy a bigger can too, but I'm a nasty cheapskate and get the 340g cans for $2 each or less.

Guys like Jimmy can probably charge by feel, but we mortals , if you don't do the mass method, can also charge slowly until you get 35F temp differential at high speed, recirc, idle 1500 rpm, 10 minutes equilibration.

I just got 35 on the VW yesterday, and 40 on SWMBOS Bimmer......smoking cold!

[abscate]

Great thread on AC performance from VRD

viewtopic.php?f=1&t=50330

[JimBee]

This is all helpful info—and I pine to be ready to tackle recharging, but am not there yet. Still fighting with springlock ("garter spring") reconnection. I did get it apart, but only after cutting off the gooseneck of the dryer to get it out of the way so I could rotate the springlock connected piece of tubing, while pulling, with the springlock tool in place.

Now I'm ready to install the new dryer. The fan and shroud are out, the mounting bracket for the compressor and alternator is removed to get a little more working room. What I don't understand is how the garter spring will expand to roll over the flare end of the dryer tube. It appears that the spring is the same outside diameter as the flare end of the tube, so basically, the flare end of the tube is pushing against the side of the spring.
There must be a trick to this, that I'm not seeing. Can somebody advise?

Related, I assume that while there is some PB Blaster in the springlock cage from attempts to loosen it for removal, it's not a good idea to lube the new spring for reconnection because that might enable the union to slip apart. True or false?

[abscate]

Some pix would help but you don't need the springs too much. The just stop the pipes from sliding out, and they will corrode into place quickly.

Squeeze the springs over the horn, connect the tubes with o rings, then push them into the receivers, maybe?

[JimBee]

Okay, I figured it out! I'll write this up with some pictures. Judging from the views there seems to be a fair amount of interest in this topic. Maybe we can edit it into a more concise and useful thread.

[jeffsws]

A write-up would be very helpful! On my to do list is replacing the dryer as rust has eaten right through it.

The springlock tool thingy to remove the dryer, where did you get yours? Volvo have their own version but is very expensive.

[abscate]

This is a common tool in a "FLAPS" or local auto parts store. I have seen it made by Lisle, Snap_ON, and others.