So i signed up for an automotive AC forum, and holy hell did i learn a lot.
Not even sure how to summarize with that i've learned. Lets try a few key bullets
According to this chart, Ford changed the oil charge level in 1989. Not sure why
The drop in charge level is due to the volume. In 1994, the evaporator was close in size to what was on the 86-93 Mustangs. The big change was the condenser. The oil and refrigerant levels were lowered as a result.
I'm going with R12 and mineral oil here. My system is all Ford parts except the condenser is a new PF style condenser, which is smaller. Instead of the 40 oz/10oz R12/oil charge recommended above, my intention is to start with 34 ounce of R12 and 8 ounce of oil.
The big takeaway with what i've learned is the condenser differences. If you are R134a swapping an original Mustang setup, you really should ditch the T&F condenser and replace it with a modern PF replacement unit. (Spectra-Premium 7-4453 condenser)
Not even sure how to summarize with that i've learned. Lets try a few key bullets
- The original Mustang condenser is a Tube-and-Fin style. Modern condensers (starting in 1994 on the Mustang) are a Parallel flow type which is MUCH more efficient. ALL of the aftermarket replacements on the market are the parallel flow variety.
- Parallel flow (PF) condensers have less internal volume than Tube-and-fin (T&F) condensers
- As a result of this internal volumn being less, you much reduce the amount of oil/refrigerant used.
- In the early days of R134a retrofits, Ester oil was added to the original mineral oil to work with the r134a. This added to the volume of oil, so it was recommended to reduce the amount of R134a to avoid excess pressure due to 1) excess oil and 2) using a T&F condenser with 134a (very inefficient)
- If doing a retrofit, it is HIGHLY recommended to ditch the T&F condenser and install a new PF condenser before converting to the 134a. You will have poor cooling with 134a and our original T&F condenser
- Since many people will install a PF condenser, they must reduce charge/oil capacity to account for the reduced internal volumn. How much is an unknown right now.
- Mixing mineral oil with Ester oil will result in more oil capacity which requires dropping refrigerant charge to avoid over-pressurizing.
Ford Refrigerant and oil capacity charts || TechChoice Parts
Oil and refrigerant capacity table for Ford vehicles
According to this chart, Ford changed the oil charge level in 1989. Not sure why
The drop in charge level is due to the volume. In 1994, the evaporator was close in size to what was on the 86-93 Mustangs. The big change was the condenser. The oil and refrigerant levels were lowered as a result.
I'm going with R12 and mineral oil here. My system is all Ford parts except the condenser is a new PF style condenser, which is smaller. Instead of the 40 oz/10oz R12/oil charge recommended above, my intention is to start with 34 ounce of R12 and 8 ounce of oil.
The big takeaway with what i've learned is the condenser differences. If you are R134a swapping an original Mustang setup, you really should ditch the T&F condenser and replace it with a modern PF replacement unit. (Spectra-Premium 7-4453 condenser)