Summer is coming. Here is how to repair and service A/C and convert from R12 to R134a. I also have a video about retrofitting A/C after an engine swap, and how to check an A/C compressor clutch if you're interested. Links below. Hope it helps!
A/C Repair, service & some troubleshooting | R12 to R134a conversion
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The real answer is, not really. If you know enough to ask the question you can appreciate changing the hose lengths may affect the volume of the system. Since the system operates based on containing a specific amount of refrigerant, a change in volume will effect operation unless balance is restored. In a stock application, adding a longer line would make the volume you put into the system incorrect. Since this is a custom installation anyways, that is partially out the window. The stock refrigerant measurements now become the baseline for some educated guessing in a modified system anyways. IMHO, the real downsides would come in when you have the cold side lines so long it cools the engine bay before getting to the evaporator core. But some insulation could mitigate that. However, I don't think that becomes a real thing until you are talking about extending the lines yards rather than inches. I'm sure there are many factors I haven't considered, but for now, I'll stick to the idea that it won't make much difference in a custom system since you have to determine base refrigerant servicing level anyways. Good luck.
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I understand the volume difference when converting to 134. About 20% less. What about the higher pressures on the high side with 134 in a stock system that has been flushed, hoses replaced, evap, replaced? My high pressure is going to 250 when ambient temp is 95 outside. Seems high. I didn't add a HP cutout. My duct temp is only 55-60*f. I thinking to bleed out a little to see if it would get cooler.
83 HO.
83 HO.
The short answer is, that's not a crazy high number at that outside air temp if the system is working to your liking. It is a little high though. I would prefer to see a number below 200, but that isn't as important as the servicing being dead on. If the servicing is absolutely dead on, continue reading.
The high side and low side numbers are equally important. If you are using a suicide gauge (the low side only direct connected to the can commonly seen in the parts store) you are not getting the whole picture. A manifold gauge set is imperative for troubleshooting. This is more of a general statement for anyone else reading as Cajun83HO identified a high side pressure so I'm assuming he has a manifold gauge set.
If the low side is a good pressure (between 25 and 40) then the freon is not being cooled or there is a high side clog. Spray some water on the condenser with the A/C on max and see if the pressure drops. if so, start by cleaning the condenser. If that doesn't work, check the fan is working properly and the fan shroud is installed. Having poor cooling while parked but working well while driving is a prime indicator of an ineffective fan and shroud. I've changed out my fan clutch for this. Electric radiator fans should be on full blast whenever the A/C is on.
If spraying water on the condenser or just driving on the highway doesn't help the A/C cool, look into flushing the system again, getting a new condenser, drier and orifice tube. The drier and orifice tube should be changed out every time you open up a system with very few exceptions. The orifice tube is cheap and a crucial part of the system highly susceptible to clogging by any debris or coagulated freon/PAG oil. If ever metal shavings are found in the orifice tube, especially after a pump has failed, it's my experience that changing the condenser is inevitable. Sometimes the evaporator too.
An under-serviced and over-serviced A/C systems act very similarly when OAT is near or over 100 degrees F. In fact, my phone really starts ringing and views on the above videos jump when the temps break 100F for the first time every year. Keep in mind, a functioning A/C system may loose 1lb of Freon per year.
Also keep in mind, a properly functioning A/C system will only cool air 40 or so degrees. A vent temp of 30F is only attainable if the air in the car stays cool and is recycled through the vents. That is why I insulated the roof and tented the window in the #FamilyBurnoutWagon.
There are so many factors at play with an A/C system it is hard to troubleshoot a system through a post on the internet. if you have anymore questions I'll do my best to get you a good answer. good luck.
The HP cutout should only cut off the pump at WOT for more passing power. Not normally a factor with the a/c if the pump is running.
Gotcha🍻
When I initially converted it over, 4 years ago, it performed the same way. I just replaced the compressor and orifice tube, because it was leaking around the shaft, and it is performing as before. Clutch and airflow are good. Same performance as if sitting in traffic or doing 70. Good enough for now.
I'll deal with it later. Have other priorities.
Thanks for your help.
When I initially converted it over, 4 years ago, it performed the same way. I just replaced the compressor and orifice tube, because it was leaking around the shaft, and it is performing as before. Clutch and airflow are good. Same performance as if sitting in traffic or doing 70. Good enough for now.
I'll deal with it later. Have other priorities.
Thanks for your help.
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