Originally Posted by chili12672
I evacuated the sytem and added 1 can and the system was reading about 100psi on the lo and hi side and won't take any more. Even though the compressor clutch is engaging, does this mean the pump is not pulling the refrigerant through.
If the ac drier is bad or plugged, will it do the same thing
100psi... engine running compressor engaged; or 100psi engine off??(Both HI & LO side will always have equal readings with engine not running...)
i'll answer you in 2 ways because reading with engine running/compressor engaged vis-a-vis reading with engine off makes a whole lot of difference.
100psi for both HI & LO side after loading 1 can would appear as normal.
ENGINE RUNNING/MAKE SURE COMPRESSOR ENGAGED:
100 psi at HI side & 100 psi reading on the LO side means that even if your clutch is working, the compressor may be faulty; OR... the expansion valve or receiver drier is clogged. (a good rule of thumb in reading manifold guages is 30-40 a the LO side and around 180 or higher at the HI side)
*visually check to see that the center bolt at the center of the clutch is actually turning when A/C clutch is engaged.
TIP FOR YOU: remember that you dealing here with a "closed" system and what happens inside it isn't visible to the eye... Unfortunately, the manifold readings give u a hint as to what might be wrong, but cannot pinpoint what part and where the fault is exactly(i.e. the clog could be in the parts mentioned, but could also very well be in the lines)... AS such, changing part per part as you go in the hope that you will find you "cure" is laborious and expensive.
The most practical way to attack your problem is to open the system:
1) test the compressor. If the center will turn freely by hand, and when u turn by hand, the "S" side will have suction, and the "D" side will push pressure when you turn we assume it to be good.
2) change the receiver drier. It's responsible for ridding your system of moisture(any air/moisture in system renders your A/C inoperative). It's cheap. $18-25.- at your fave auto shop.
3) change expansion valve. it's usually a problem part when we talk of clogging... beacuse it's job is to force freon through a very tiny opening to provide the "cool" we look for. THE AVERAGE COST IS ABOUT $35-45.00
4) while the receiver/dryer and expansion valve are still out, blow all of your lines with compressed air, or flush if possible. This is to check whether your lines are actually free of debris. If at anytime, compressed air cannot pass through say the evaporator lines, or the condenser lines, then you have found THE clog in your system ;-)
5) if the lines, evaporator, and condenser pass compressed air freely... then let's start ur re-install. :-)
6) renew all the o-rings ith A/C grade o-ring seals. make sure they are oiled with PAG or ester oil before install so they don't bind in their sockets, and also to improve the sealing quality.
7) re-install expansion valve & receiver/drier.
8) vacuum and test ur system for leaks. A good job will show in the amount of vacuum your system can pull. Within 15 mins of applying vacuum, your system should be able to hold a 30in. vacuum(it should show on your manifold guage- the negative #'s on the LO side scale is what u use for this)
9)close both manifold knobs, and disconnect vacuum. Observe the meters. Both high and low side meters should be able to hold their respective positions in a negative reading for at least 10 mins.
10) if YES, it is holding - CONGRATS, you did a good job and are now ready to re-charge your system with new R134a; if NO, needle moved leftward to the "zero" mark, your system has a leak. RE-CHECK your work.
11) introduce you oil charge if u haven't done that when u tested the compressor, followed by the recommended amount of R134a which is in your case 1225grams +/- 25grams.
*it sounds complicated at fist, but all the above steps can be done in an hour. ;-)
Good Luck and have fun :-)