Automotive Air Conditioning Information Forum

Ok, so i had the system evacuated and recharged with 42oz of r134a.

Additionally, i decided to clean up the impact marks on the condensor and straighten the fins. There was quite a bit more of it than i originally thought. There was also still quite a bit of dirt and tiny rocks in it, so after ...

I've cleaned the condenser twice now with simple green and feel confident that its clean.


Tested temps and pressures again today

Current ambient temp is 97

At idle:
Low 65psi
High 325psi
Vent temp 72

At 1800 rpm while parked
Low 75 psi
High 425psi
Vent 62


Since the system being over charged ...

Bohica2xo

Yes I understand. I tried to lay that out in the posts just after the original. It dawned on me after the original post that it would be relevant information.

How do you think i should proceed?
Evacuate the system, pull a vacuum and recharge to oe spec, then test?

With the uv dye ...

Checked cooling fan clutch- doesn't appear to be any issues there. Spins appropriately before having started the truck, spins appropriately compared to motor rpm, doing a "newspaper test" didn't even try to slow it down.


Looking at the condenser it's wasnt particarly dirty. But i cleaned it anyway ...

425 psi is a condenser issue, not a weak compressor.

Generally an airflow issue. Condensers clog deep in the fins with small debris & insects. The face can look clean & still be plugged.

Wait for dark. Hang a shop light or bare bulb in the radiator shroud, and start looking straight through the ...

Yes, mechanical fan with clutch. Not electric. Thank you for the reply. I'll look into testing the fan clutch.

Just checked for uv leak.

Only thing i could find was a light haze of the green around the compressor clutch. The circular part of it, not the triangular plate, but just behind it.

You can see it in this photo link: https://photos.app.goo.gl/jZRDILQuZcLkPXDH2

Also visible between clutch and ...

Additionally, this was first really evident about 2 weeks ago. I don't recall all of the temps and pressures at that time, but the low side pressure was 45 with an ambient temp of 97.

https://photos.app.goo.gl/bdECHfq0TS80NMYs2

So using this chart i added freon and got the liw side up to about ...

99 Ford F250 super duty V10 Gas

AC has progressively got to the point where it doesn't cool at idle, but cools some when driving. (But still not like it used to)

Ambient temp today 94

Center vent temp at idle was 74
Center vent temp @1800 rpm when parked 66

Pressure Readings at idle:
Low - 75psi ...