There seems to be some disagreement in the amount of coolant needed to fill the air conditioning system in the 1995 4.0L X300(XJ6). Does anyone know what the correct amount of coolant is needed to reservice this system? I am replacing the compressor and want to do the job right.

Thanks guys.

 

http://www.ariazone.com/brochures/Re...ty%20Guide.pdf

1150 grams or 40.56506 ounces.

When I did my 97's compressor I used 2 1/2 16oz cans. That was over 2 years ago and she's cooling great. I ordered my Denso compressor from Rock Auto also and was far cheaper then anyone else with no core required.

 

Hello JTsmks,

I just received my new compressor yesterday and will be installing it next week. I'm looking forward to the cool breeze in the heat of summer!!

Section 14 (Climate Control Systems) of the XJ6 Vehicle Service Manual states that the charge weight is 1100g +/- 50. The lubricant capacity is 160 - 200 ml total.

The only accurate way to charge an empty system is with a scale; weighing the cylinder at the start and monitoring it until the cylinder weight has decreased by the proper amount to be transfered to your system. You also need to ensure the proper amount of lubricant is added. This should only be PAG oil for the x300's. The way to determine the proper amount is given on pages 13 and 14 of Section 14 which follows. You should be able to properly charge your system with 100% accuracy (within the tolerances allowed) following the manual info...

14.9.4
Adding Lubricating Oil - Compressor Related
The amount of oil drawn out during a recovery procedure will be dependent on the state of the system and the rate
of recovery. The quantity will be approximately 30 to 40 ml; this may vary, and the figure is given only for guidance.
The oil separator vessel in the recovery equipment must be clean and empty at the start of the process so that the quantity
of oil which is drawn out may be accurately measured.
Oil may be added by three methods, 1 and 2 being direct into the system and 3 with the compressor off the vehicle;
1. Via the recovery / recycle / recharge station.
2. Proprietary oil injector.

Note: Equipment manufacturer's instructions must be adhered to when using direct oil introduction.

3. Directly into the original, or new unit, because of rectification work to the existing compressor, or the need to fit
a new compressor.

Original
From an existing compressor, drain the oil into a measuring cylinder and record the amount. Flush the unit out
with fresh PAG oil and drain thoroughly, Replenish the compressor with the same amount of PAG oil that was
originally drained out and immediately plug all orifices ready for refitting to the vehicle.

New
Drain and discard the transit lubricating oil from a new compressor before it is be fitted. An adjustment must
then be made to avoid over-filling the system, by taking into account;
a) the quantity found in the original compressor.
b) the quantity deposited in the recovery equipment oil separator from the charge recovery operation.

Typical example:
Drained from original compressor 50 ml
Recovered from oil separator 40 ml
Quantity to be put in new compressor 50 + 40 = 90 ml

Please note that the discrepancy between the cumulative figure of recovered and drained oil and the nominal capacity
of 180 ml is caused by normally unrecoverable oil being trapped in components such as the condenser, receiver/ drier
or evaporator.
The previous statements apply even if a problem has occurred due to oil leakage. The amount of oil lost due to leakage
is generally small, so to avoid over-filling please follow the example.
If however the recovery process has not been necessary because refrigerant has also been lost, then ONLY replace the
quantity drained from the original compressor.

14.9.5
Adding Lubricating Oil - Component Related
Should a major component such as condenser, receiver / drier or evaporator be renewed then an adjustment to the
system oil level must be made. This may be carried out in the same way as the examples for the compressor except
for the fact that trapped oil within any one of these components cannot normally be drained. Therefore, a nominal
amount of oil should be substituted in addition to that recovered from the recovery station separator.

Condenser Add 40 ml
Evaporator Add 40 ml
Receiver / drier NO adjustment

CAUTION: Always decant fresh oil from a sealed container and do not leave oil exposed to the atmosphere. PAG
oil is very hygroscopic (absorbs water) and will rapidly attract atmospheric moisture.
PAG oil must NEVER be mixed with mineral based oils.
Do not re-use oil following a recovery cycle, dispose of it safely.

Best of luck and work safely!
Bob

 

Well..............I can tell you, I added the amount of oil to the new compressor by the amount poured out of the old compressor, evacuate, hold a vacuum, evacuate some more then add 2 1/2 cans of R134A...2 years later in sunny, hot Florida she's cooling just fine. If you change out all components (drier, condensor and flush all lines) then you'll have no oil in the system...most take 7 to 10oz's total of PAG which can be added by approx 4 to 5oz's to compressor, 2oz's to drier and 3oz's to condensor. The compressor should always be hand turned approxamatly 10 times once installed to prevent oil slugging on start-up. If you change out the drier with the compressor (recommended) then add 2oz's of oil to the receiver/drier on install.

 

My apologies JTsmks...the original reply I posted was intended to be to the original poster of this thread, EZDriver. It was late after a long day at work when I posted that and mistakenly addressed it to you.

You bring up some important points and I'm glad you did; namely replacing the receiver / drier (always good to do when opening the system), evacuating and holding a good vacuum, and the point of rotating the clutch pressure plate.

I'm glad your AC is working well for you. Personally, I prefer to not use off the shelf cans to add refridgerant having learned that it is too easy to end up with an improperly charged system. Following the service guide is always the best way to go.

Bob

 

Bob, I'm certified and have been servicing A/C systems here in Florida for over 25 years (not even close to my primary job just decided to quit paying people to do what is easy to do by any mechanically inclined person) and have only used off the shelf can's and have never had a problem one....it's not a black art it's a liquid that turns into a gas and therefore cools through the expansion process. A little too much or a little too little one way or the other isn't going to effect things that much just like one oz too little oil or one oz to much isn't going to break the bank either way. BIG problems start when the orifice tube is pulled and it's covered in black or worse yet metal particles...need to flush lines, replace condenser, flush evap and I put a pre filter just at the compressor entry for good measure to ensure long life and no stray "flakes" find their way in. Or when people blindly put 3 cans in thinking it will cool better with more in it.

 

Thanks to all you guys. This has been a great response. I do have some experience with ACs and find the information presented to be excellent and very helpful in refining what I plan to do. I will post results as soon as they are solidified.

Thanks again.

 

Hey guys. I hate to keep bothering you guys, and seeming like a dummy, but I like to check all the details. Old aviation habit.

Am I correct that the coolant in the 95 XJ6 is R134a. And somewhere I read that the O ring seals should be green to be compatible with R134a. The Denso compressor I just received had black O rings. Are the black O rings not compatible? Am I just being overly careful?

 

Yes R134A is correct. The colour of the o-rings isn't important, some nitrile o-rings can be black although green is more often seen.

happy motoring

Larry

 

They are fine.

 

My system is leaking, and I'm guessing it's time to tear it down and replace all the o-rings. When I add freon, it runs great... for a day.

Is there an o-ring kit and a step-by-step (other than what's included in this thread) for the x300?

This is a great reason to by some vacuum gauges, and I already have a vacuum pump.

 

You can buy a big A/C "O" ring selection at most auto parts stores or Harbor Frieght. Best thing is to put a little "dye" in the system and find out where the leak is...very unlikely you'd need to change all of them out. Plus you may have a leak at the evap or condenser, which would make changing out "O" rings pointless.

 

Agree with JTsmks, find where the system is leaking before doing anything! A 21 LED UV light from eBay and a shot of dye is the way to go. It's also possible that your system already has dye; a lot of 20 year old cars have dye in the systems already. You'll still need the UV lamp and a pair of yellow safety goggles to spot the leaks though.

My late '94 Xj40 with factory R134A shares quite a few components with the X300 and apart from the condenser to high side hose connection, the systems are very similar. When I rebuilt my a/c last year I too ordered one of these large selection o-ring kits. Although there were several I could use, (receiver/dryer connections etc) the kit didn't have the sizes needed for the pressure switch/hose connections - I had to get those from the Jaguar dealer.

Larry

 

I have a set of nitril o-rings, too... (but, I guess I need metric )

225 Piece Nitrile O-Ring Assortment