Vince, late to the game here, but that debris is from the compressor. With system operating (R134a system) I like to see 30 psi on the low side and 150 psi on the high side. As a rule of thumb outlet duct temperature should be 20 degrees less than ambient when vehicle is stationary. Been a while since I performed R12 to R134a conversion, but seems that the 134 system charge is 75-80% of the R12 system capacity. Good luck
That's what I was gathering.
At 73 degrees yesterday, I was getting damn near 200 psi on the high side. Needs to be more like 125 psi at operating temp
Then when the truck got warm, the already high pressures increased, heat started building, then the truck started getting warm... Whole analysis went to hell.
I have to replace the clutch fan before I revisit this, following that, I suspect I may need to bleed off a little freon.
Low side was at 30. I'm fine there. I'm slightly overcharged and the worn out clutch fan isn't doing its job anymore.