Didn’t you consider upgrading to parallel flow condenser?
Or a cable…20 characters.
We did the aluminum compressor on the e-type, with R134. Works great, plenty cold. I will do same on my XJS at some point, but as of today my 12 yr old setup of reman iron compressor and R12 is still frosty.
another question, it seems getting the right amount of PAG oil into the system is a crapshoot. Too little and you can ruin the compressor, too much and you don’t get maximum cooling.
My non-Jag requires 6.75 oz total for a full dry fill.
It says for a new condenser add 1 oz to it, and for a new dryer add 2 oz to it. I assume i can just pour it straight into these parts before hooking them up.
When the old condenser got punctured, the R134a leaked out very fast. So I should probably put in an extra 1 oz for hoses and such? That would be 4 oz, assuming 2.75oz still exist in compressor and evaporator.
ALso, it says to put oil in and THEN vacuum. So the vacuum won’t remove any oil? how does it suck out air and moisture without sucking out oil?
I’m just being an idiot here , but I concur with what Bob says.
Bob didn’t know you still came to JL’s website. You inspired me to clean up my engine bay and I still didn’t come close.
Apologies everybody, I didn’t mean to hijack the thread.
Back to AC questions, Gary…
1 Like
A cable would presume it’s spring-loaded in one direction. Or that you’ll be adding a spring to pull it in one direction.
Not necessarily; friction vent cables were common in many non-a/c domestic cars. Or, if you want fancy, use a light aircraft throttle cable with a friction lock.
Every A/C system I’ve opened had been under oiled. The chances of putting too much in when adding that little are minute.
The vacuum removes air, and water vapor by boiling whatever water is in the system. The oil doesn’t boil.
You are overthinking this. Add the oil, put on the new receiver/dryer, vacuum the system, put in the R134a, and enjoy. It’s not rocket science. Put in the R134a by weight since you are starting from zero. The sight glass method makes it to easy to overcharge wìth R134a.
2 Likes
Interesting. I heard somewhere that systems tend to be overoiled, apparently because people add oil when they hadn’t actually removed as much oil as they thought they had.
How? Add until there are no bubbles. Couldn’t be simpler.
Because small bubbles sometimes still appear even in a fully charged system with r134a. If you keep adding you can lock up the compresser. In his case he’s starting from zero, so weighing the correct amount is the proper method. Read the Jaguar retrofit procedure. Doesn’t mention the sight glass anywhere. It says to put in 1150 grams (40.5oz) of r134a. Any professional will tell you that if a system is low on r134a, the correct method is to evacuate and recharge by weight. No gauge or sight glass will provide an accurate indication of the correct level of r134a. In his case, assuming 12oz cans, a little over 3-1/3 cans.
You’d have to add a ton of oil. The problem is people using refill cans with oil any time they top off. Or dumping a bunch of oil in the low pressure side at once that liquid locks the compressor. He’s talking an ounce of oil at the condenser.
I’ve drained several compressors from systems still pressurized that had no obvious leaks, and invariably, there was little oil present. It was scary how little was there. The lines and rest of the system were flushed, and little oil was present. One time was a system that had never been opened from new. Where it all disappeared to, I have no clue.
i’ll be putting in the required 2 oz. of oil in the dryer, 1 oz of oil in condenser, and 1 oz extra oil into condenser based on my fast leak. So adding 4 oz on a system that takes 6.75 oz should be in the ballpark, having had a puncture in the condenser and replacing that and the dryer. BTW, the required oil was PAG100 synthetic.
My non-Jag says to add 36 oz of r134a from empty. So three cans exactly.
What’s strange, my non-Jag doesn’t have a high pressure valve! So I will have to vacuum and charge through the low pressure valve only. Is this normal?
I could see this when average people charge their systems themselves, and buy the R134a that comes with oil. I had a hard time getting the plain R134a at Oreilly’s yesterday. First she brought me R134a with stop leak, I said no. Then she brought me R134a with leak detector. I said no. Then she brought me R134a with oil. I said no. FINALLY, she brought me R134a, plain.
Buy it a Walmart. Cheaper, and easy to get without oil. $4.50 a can near me.
Fill it with 40.5oz. That’s the XJS R134a retrofit spec. Or are you talking about another car? Every car has different fill amounts.
About your non-Jags port. I’ll bet it has one somewhere. Often they are well hidden. You can pull vacuum only from the low side. And you NEVER try to fill from the high side. New cans have valves that try to prevent back pressuring from the high side, but don’t depend on that to keep the can from blowing up if you accidently open the high side valve while filling with engine running. Best to leave the high side hose disconnected when filling. Hook it up after filling to check correct operation of the compressor and expansion valve during operation.
yes, i’ll disclose, i’m doing this all on a Volvo 850. I will eventually do it on my XJS, so this is my learning experience for the Jag. Cans at Oreilly were $7 each. Oh well.
No, i checked service manual, the Volvo does not have a high pressure port.
Weird. I wonder how you are supposed to troubleshoot with no high side valve? Does the HVAC controls/display have a service mode to read out pressures or something?
Then it’s not fully charged. It is fundamental to the operation of a refrigerant circuit that the liquid line contain only liquid. Doesn’t matter what refrigerant is used. The notion that bubbles are acceptable when using R-134a is a myth.
Here, check out this servo:
Even comes with a lever, and it’s dirt cheap.
Not that I know of. Although there is an electric sender hook up to the high side, so the ECU must know what it is. Not sure how to access that, i do have a code reader, so I’ll see if that can read it.
The car is 24 years old, and until the condenser got punctured, the A/C worked nice and cold. Original compressor.
Maybe that’s a good idea, or not, I dunno.
What I do know is, if you can be so bothered as to first removing the center console, then the steering wheel, followed by the dash, then the heavens will open up to you and the glory of the climate control box will be revealed to you. Disconnect the hoses from the engine firewall side and the two nuts holding the CCB in place. Disconnect the vent tubes from the CCB under the dash and proceed to pulling that CCB out of the car and get it setup on the bench. I can pretty much guarantee that you will find a fair amount of work to do on that box in order to bring it back to proper working order. Remove the evaporator and you are sure to find a fair amount of crud buildup in the fins (more than likely that’s why people complain about lack luster cooling) to be blown and cleaned out. Take it to a radiator repair facility for a proper flush and pressure testing (I’d be taking the heater core along for the ride as well.) Before fitting the evaporator back into the box take this opportunity to flush it out properly with a can of ac flush, you’ll never get a better chance to flush this well again, and certainly not as good as flushing it when mounted in the vehicle. Crack that box open and wash it out real good with soap & water then strip all of the old disintegrated foam off of the flaps and everywhere else in that box and replace it with new and better materials. There will be no better time to remove and test the functionality of the servos in hand with a 9V battery. Once everything is put back in place and the box is buttoned up make sure that all of the vacuum hoses that attach to the box don’t slip off when refitting. If you’ve changed the expansion valve (and you should) make sure and wrap it real good with that black gooey type stuff so that it is isolated from the heat. Change all of the ac hoses on the engine side to the barrier type that is used for 134a whether you use 134a refrigerant or not. When changing the condenser avoid the temptation of using parallel flow types, the pass through tubes are just too small and once they get clogged with dirt, there’s just no cleaning them. When adding oil back into the system it is advised to figure the total amount to be used and divide that amount into appropriate amounts to be spread around the system. For a hypothetical illustrative example: If the system called for 10oz. you might want to add 3oz to the compressor, 1oz to each of the hoses = 2oz, 1oz to the evaporator, and 4oz to the condenser. It would be ill advised to add all 10oz to the compressor because the compressor couldn’t handle it, and it would be equally ill advised to dump the lot of it into the condenser in hopes that it will be circulated throughout the system (it will not). I am sure that I left out a few details here and there, but that is pretty much the exercise that I went through.
The weather got cold by the time I finished all of that and because of dismantling a lot of other things I have been unable to start the engine and test it out yet. I also wanted to be able to preform the final testing with ambient winter temps, but now that the season is starting to change and the ambient temperatures are starting to approach 21C°/70F° I will pump Nitrogen into the system and then proceed with the vacuum process before adding the 134a to my newly converted R12 system.
1 Like