Banshee365

1996 had a working A/C system until a leak developed. Had to add refrigerant every week or two. Turned out the compressor front seal and evaporator core were leaking. Replaced them both from a salvaged car that had 70k original miles on it. Parts looked really good and it saved me alot of money. I did not replace the expansion valve as it was working fine before i took it all apart and I made sure all of the fittings were clean before reassembling. I did replace the drier.

Here is my problem. The system is charged with 1.6 lbs of refrigerant, which is right at what Lexus say's it should hold in the factory books. This is a big A/C shop so I can't see that they let the car run for a while before they checked the pressures. The low ran at 60 psi and the high at, GET THIS, 350 PSI. Temp outside was about 95 deg in humid FL. The shop seemed really concerned that it was that high that it could blow the condensor or the blow-off valve if it goes much above that. They were also saying the vents were blowing 60 deg. When I drove the car home the vents felt like they were blowing alot colder than that, especially with an RPM above idle and moving down the road. It seems to be working just great but the 350 psi head pressure really concerns me. The compressor was working as it's supposed to in the salvaged car before it was taken out. Let's assume I have the right amount of oil in it that I replinisher per the Lexus manual and that that's not the reason why, if it could even cause high head pressures. Here are a couple of things I'm thinking, what do yall think:

1.) Maybe I filled the drier with oil through the wrong hole. I poured some oil in the drier that looked to have something just below it which could be the desicant bag. It that filled with oil could it cause a restriction and caues the high pressures?

2.) I didn't change the expansion valve. There are no kinks in the little copper line. The suction line coming from the firewall going to the compressor get's REALLY cold when it's running. It's not totally frozen over with white ice and such but it's hard to touch for more than a few seconds.

3.) Is the compressor bad? I see it as being something else than the compressor. Maybe a restriction like a mis-filled drier or something?

Thanks for the help in advance guy's, any ideas?

-Kelly

python

iTrader: (4)

did u vacuum the system out ?

GEORGE_JET

Sounds like there is a little too much freon in the system. I would suggest removing some and re-checking. Even the low side sounds high.

Banshee365

The shop put a vac on it and it held for an hour or so then they charged it up. Wish I had the equipment to evacuate, vac, and charge myself so I could take the shop's work out of the equation.

Banshee365

I noticed today that, even with the car at hot operating temp, the electric fan in front of the radiator/condensor does not turn on. I don't remember hearing it run for the longest time. This could cause the high head pressures when sitting in a 95 degree shot with gauges on it right? I need to get that sorted out. Going to search the forums and see what I come up with. Don't really know where to start in the factory books. What do yall think?

-Kelly

JimsGX

Maybe Check This Out...

https://www.clublexus.com/forums/ls4...t-turn-on.html

nthach

You've got a blockage somewhere. Was a death kit used earlier in the car's life?

Banshee365

The car has alway's been 134a. I never put any miracle sealing agents in the system either. I did not change the expansion valve because of a cost issue and because the compressor didn't come apart, it just started leaking in the front seal. The AC works awesome but the shop telling me I have high head pressure kind of scares me. The fan has been coming on at low speed with the AC on and the car warmed up. I think it has to get pretty hot for the fan to kick into high speed.

The suction line from the firewall to the compressor get's super cold but doesn't quite ice over. It would seem that if I had a bad blockage that the AC wouldn't be all that cold but it seems really cold, especially when you're driving. I just paid to have the system charged and don't know if it would be worth it for me to take it down again just to remove the condensor and flush it or something unless I knew for sure there is a problem in there.