Member Since: 30 Jul 2013
Location: Waterlooville
Posts: 58
AC compressor replacement
Hi,
I am about to replace the AC compressor and the condenser of my disco 3. As the new Denso AC compressor comes with pre-filled oil for the entire system, I was wondering if I should remove some of the compressor oil?
From the manual I can see:
A/C Compressor Replacement
A new compressor is supplied filled with a full charge (X cm³) of refrigerant oil.
A calculated quantity of oil must be drained from the new compressor before installing. To calculate the quantity of oil
to be drained:
Remove the drain plug from the old compressor.
Invert the compressor and gravity drain the oil into a calibrated measuring cylinder. Rotate the compressor
clutch to make sure the compressor is completely drained.
Note the quantity of oil drained (Y cm³).
Calculate the quantity of oil to be drained from the new compressor using the following formula:X cm³ — (Y
cm³ + 20 cm³) = Q cm³
Remove the drain plug from the new compressor and drain Q cm³ of oil. install and tighten the compressor
drain plug.
Does this takes in consideration the replacement of the condenser?
From the denso manual I see below, and get confused even more.
Click image to enlarge
Thanks,
Tiho
5th Jun 2025 1:55 pm
PROFSR G
Member Since: 06 Mar 2017
Location: Gulf of MEXICO
Posts: 5382
You're overthinking it!
The system will have to be vac checked before being regassed with refrigerant, and it's at this service point any old oil will be extracted from the entire system.
With modern AC service equipment the operator will (should) have the correct vehicle details of how much oil, fluorescent dye and gas to program into the machine.
You could for safety just add 10ml of oil to get you to the service provider, but either way you must leave the AC in the "off" position until the procedure has been carried out. yµ (idµ - eAµ) ψ=mψ
5th Jun 2025 2:20 pm
logche
Member Since: 30 Jul 2013
Location: Waterlooville
Posts: 58
Thanks PROFSR G,
That makes perfect sense. And hence mine is 7 seater and have AC on the back, but it is blanked, how much gas it should take?
Click image to enlarge
I guess somewhere between 550 and 810, as there are still some lines going to the back before they are blanked.
Thanks,
Tiho
5th Jun 2025 4:27 pm
PROFSR G
Member Since: 06 Mar 2017
Location: Gulf of MEXICO
Posts: 5382
550g is enough. To be on the safe side measure what oil you recover from the old compressor and subtract that from the new one as per your chart.
It would be a good idea to inform the person recharging the system you have done this, and that it's not a max regass but 550g as per the slam panel label.
Ps I hope you're up for a fight with the removal/refit! yµ (idµ - eAµ) ψ=mψ
You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot vote in polls in this forum
