since i have a couple of days of free time i would really like to dig into my ac and figure out this issue. first of all i have a bit of a weird musty smell and form what i have read we do not have cabin filters.

here is what my gauge sets are reading with the ac off and then on.
what should it be reading, im new to anything ac related

sorry about the messy engine bay!



NEW PICTURE- truck on, ac on, compressor tripped on with paperclip.



with truck on, ac on max, compressor not spinning



with truck off, ac off



i suspect this could be a leak?



if i jump that with a wire compressor works



could sensors be the cause?




what is a good way to tell if there is a leak? how can i trouble shoot a bad orifice tube? what is the cause of this odor im smelling with air on (mold somewhere im assuming)?

 

First your low side looks way high and your high side looks very low not good. This usually means a bad compressor from my understanding. Look here… http://www.aa1car.com/library/ac98.htm

What you think is a leak is the connection were your orifice tube is you open that connection and fish it out sometimes easy but most times they are in there tight and they always look like they are leaking it’s the tar like insulation wrapped around it it weeps.

Sensors are normally good for many years and if they didn’t work you wouldn’t see the A/C clutch working at all.

Everything looks original meaning you should replace the Receiver-Drier/Accumulator the black thing with three tubs sticking out of it and the orifice tube should get replaced also.

You’re A/C looks original and beat up its time is up or close to it.

Gauge Chart... Attachment 16253

 

sorry mike i had my pictures mixed up.


when the truck is on ac switch is on my pressures on both sides are 25psi. from looking at the picture and with it being about 70f today my low should be at about 35-40psi and high should be at 145-160.
would this be the cause of why my compressor is not turning on because of the simple fact the switch is telling it not to turn on due to low pressure?

also the picture of the line i mentioned. would it be a good idea to replace it? how can i go about finding leaks? im almost positive that it is a leak, i refilled it last spring and working fine for a couple weeks then boom no ac.


now what is the flushing of the system that ive been reading up on and am i required to do it?
i was reading up on vacuuming out system and recharging which im fairly confident i can do.

here is of the flushing which im confused
AC System Flush - AutoZone Car Care - YouTube

here is a video that i think can help me out with vacuum and refilling
How to evacuate and "pull" vacuum on an R134a car AC system - YouTube
Part 2. How to properly charge an auto AC R134a refrigerant air conditioning system. - YouTube

by the way what a difference as you can tell this truck being located in the northeast compared to yours which is spotless!

 

I suggest take it to a shop for a free A/C inspection you can find them just make sure it is FREE read the fine print and ask IS IT FREE make sure they know it’s not working because they may charge you if it’s not working so make sure it’s free?

Start from there.

When a system is as old as yours it could be a dozen things at the same time if you know what I mean.

 

Flushing Hmmm well its a good thing to do but a lot of work if you dont have the Black Death then you could get away with just replacing parts.

Ok replacing the dryer is a good thing and the orifice tube also.

Replace all the O Rings

The leaks are so hard to find it can drive you crazy look for oil build up were there are leaks their will be oil usualy.

Its so hard to explain all the things needed in words how to replace these things

 

I’m in the process of changing out a lot of my old A/C and radiator parts and have started a web to show these things but it’s in the works so its way incomplete.

But may help you


Look here... http://dakota-4.com/

 

Brian, when the compressor is off the pressures will be more or less equal as you're showing. This is normal. Since there is a slight difference is pressure between the two readings I'm thinking you're low on freon. Maybe high enough to start the compressor but an almost instant trip on the low pressure cut-off when the compressor starts up.

Jump the low pressure switch and with the compressor running find out your pressures then you can diagnose the system. If the system hasn't been opened you shouldn't need to replace any parts.

Start with the basics first. It's not uncommon to have to jump the low pressure switch to get it to accept a charge.

 

Ok here is the orifice tube with an old one and a new one thats purple.

 

00DakDan

But he is loosing freon that needs fixing first but you will need to get some freon in to test for leaks if you can get it pumping that is.

At 25 you should still get the pump working I have been down that low and my A/C still pumps.

If you do plan on changing the orifice tube and or dryer and all your O rings you need to evac the freon first.

 

The problem is if you just keep pumping in Freon you are never finding out were the real problem is open it up and replace the two parts I talked about install new seals pressure test if no leaks pump her up.

Orifice tube $5
Dryer $35 to 65
O Ring kit $10

And the Freon $40 to $55

Not hard to do and a better possibility you will fix the leak and get better A/C for the next 5 years or more.

What’s the saying do it right a patch is a patch