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Radiator Coolant exiting Low Pressure Port / Water Pump Replacement (Double Jeopardy)

It might be worthwhile for you to get a basic understanding of how heat pumps work. I can only imagine that internet searches result in thousands of hits, most/all of which concern technical minutia of problems that are make and model specific. You need to start with automotive AC for the complete idiot. I’m sure there’s one out there somewhere. The McParts stores should include some basic information with their Freon grenades.

the 100PSI is an erroneous reading. Probably happend when the trigger on the refrigerant can was release after attempting to top off the system. I believe the author mentioned somewhere that the PSI was 30 on the low side. Touch low on refrigerant.

When I was employed in A/C service, you did not use the low and high side pressure readings until the compressor was turning. A low side pressure of 100 would depend on the temperature of the system. I don’t have the temperature vs pressures for R134a. To fill a system the compressor has to be running. I am not familiar with the modern systems but the legacy systems had a sight glass on the receiver dryer. Unless you were filling a completely empty system by weight, you added refridgerant until the sight glass went from frost to flowing liquid. You monitored the high pressure side to make sure the system did not get overfilled. When our shop did system services a few ounces of oil was added as a matter of policy. Systems lose oil sealing the compressor shaft seal and the seals of the connections. If a component was replaced, the oil was removed from the old part, weighted, and the appropriate ounces were added to the new component i.e compressor, condenser, receiver dryer, evaporator, etc.

times have not changed. There is only so much that can be done to improve a car’s a/c and the only thing that has come to change is the type of refrigerant we use today. Most over-the-counter brands contain some oil.

I still remember a time when I tried to install an under-the-dash a/c in a Fiat 500. It was given to me free and, of course, never worked unless you expected warm air.

Happens to be a Ranger (danger) in this video…

From Chapter 3-11 of the Chilton Manual (section 14-4):
“4. Because of the complexity of the air conditioning system and the special equipment necessary to service it, in-depth troubleshooting and repairs are not included in this manual. However, simple checks and component replacement procedures are provided in this Chapter.”

Bikes are so much easier to deal with and when you coast downhill, you have all the A/C one could ask for.

Solution: Relay switch was blown. System was recharged. Took the vehicle to the dealership to have passenger airbag inflator replaced (recall 15S22) and had A/C system evaluated. $160 out the door.

Good for you. Glad you got your airbag fixed too as well as the AC. That manual you have on cautions for diy’er fixing of AC systems is correct. Federal regulations on newer cars place a limit on how much refrigerant can be used in the AC system. Cars of yesteryear might have used several pounds, newer cars may use as little as 12 ounces. The proper way to recharge for these is to pump all the refrigerant out first, then once it is evacuated, pump exactly the right amount back in. Overfilling can do a lot of expensive damage. On newer cars, best to leave AC work to someone experienced and who has the needed tooling and equipment. $160 out of pocket and a working system is a lot better than $50 and a non-working damaged system requiring thousands to repair.

Now, to have my rear trans-axle rebuilt. U-Joints are worn and bearings are needing to be replaced. I can hear it (bearing whine). Also, when you press on the accelerator, you can feel a delay. I thought it was the motor mounts but technician says otherwise.

Thanks for all the input and feedback regarding this topic.

One method commonly used to confirm a pinion bearing problem in the differential is to bring it up to the speed where you hear the bearing whine, then go a wee bit faster, then let your foot off the gas. If the bearing whine goes away and doesn’t return as long as your foot is off the gas, that’s consistent with a worn pinion bearing.

Replacing a pinion bearing – if that’s what you need – can have some complications. You might want to take it to a differential specialist.

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