Time for A/C Rebuild

[AmericanSavage]

mat in tn wrote

this is a very common problem with semi hermetic systems. the crankshaft either does leak or will leak.  a perfect seal is very difficult, yet many achieve it, so we know it's possible. I'm not sure about blaming a distributor for selling the parts that are available. obviously for is no longer making these for our trucks. it is disappointing how much crap is sold for us old car guys. reman is my method over new.

Hey Matt,

Yes, poor wording on my part.  It’s like we make nothing well anymore.

[AmericanSavage]

viven44 wrote

Thanks. How much PAG46 oil did you use ? Should have used around 7-8oz.

also the high side pressure seems a bit low... indicating a compressor problem.. should be north of 200 if the low side is 30-35, assuming the ambient is 80C or higher.

Per documentation at
https://www.garysgaragemahal.com/hvac-systems.html

I have about 4-5 in it.  I was looking at the Light Manual and it does indeed say 7-8—I missed it somehow.  However, I have not run this a lot with the air on so I am not sure if there was any harm here.  I have some PAG 46 on the way, HOWEVER, I highly doubt that will fix my leak issue.  Yes?  IT MAY, I suppose, calm down that rattle when the clutch engages?

Appreciate the comments.  FRANKLIN2 suggests I try some spray bottle soap water all around for leak spottage as well, which I may do today.

[viven44]

https://www.autozone.com/cooling-heating-and-climate-control/a-c-system-oil/p/a-c-certified-pro-r134a-pag-46-with-uv-dye-refrigerant-oil-8oz/667637_0_0

I always use that oil as it provides a visual cue on leak

Without adequate lubrication, the compressor will have a short lifespan. That said, I dont think 4-5oz was probably low enough to immediately kill it...

If you have a compressor shaft leak (Which appears to be the case based on the video), it is difficult to spot with UV dye though...

I'm afraid you are heading down the path of compressor replacement if you cannot build high side pressure of at least 200PSI.. that much is a given

And one more thing is... everytime you remove a manifold gauge, unless you do it a certain way it will cause refrigerant loss through the high side as there is refrigerant stuck in the high side hose.

Here is what I do to disconnect just based on what made sense to me (idea is to remove all high pressure / volume of refrigerant from the high side/discharge side and send it into the system through the low side/suction side)

1) Assuming you have the manifold gauge hooked and both the high and low manifold valves closed, Turn off vehicle
2) Close the high side service port valve (assuming your gauge set has a valve there) and remove it from the service port
3) Ensure middle (charge) port is sealed to outside
4) Open the high side and low side manifold valve. This will send all the high pressure gases into the system through the low side port. You will see the pressure equalize between the low and high side gauges and settle at ~70PSI or so
5) At this point, CLOSE the low and high side manifold valve
5) Turn on vehicle, and assuming the low side service port valve is the only thing open, the system should suck whatever is left in the low side hose
6) Close and remove the low side service valve

[AmericanSavage]

viven44 wrote

https://www.autozone.com/cooling-heating-and-climate-control/a-c-system-oil/p/a-c-certified-pro-r134a-pag-46-with-uv-dye-refrigerant-oil-8oz/667637_0_0

I always use that oil as it provides a visual cue on leak

Without adequate lubrication, the compressor will have a short lifespan. That said, I dont think 4-5oz was probably low enough to immediately kill it...

If you have a compressor shaft leak (Which appears to be the case based on the video), it is difficult to spot with UV dye though...

I'm afraid you are heading down the path of compressor replacement if you cannot build high side pressure of at least 200PSI.. that much is a given

And one more thing is... everytime you remove a manifold gauge, unless you do it a certain way it will cause refrigerant loss through the high side as there is refrigerant stuck in the high side hose.

Here is what I do to disconnect just based on what made sense to me (idea is to remove all high pressure / volume of refrigerant from the high side/discharge side and send it into the system through the low side/suction side)

1) Assuming you have the manifold gauge hooked and both the high and low manifold valves closed, Turn off vehicle
2) Close the high side service port valve (assuming your gauge set has a valve there) and remove it from the service port
3) Ensure middle (charge) port is sealed to outside
4) Open the high side and low side manifold valve. This will send all the high pressure gases into the system through the low side port. You will see the pressure equalize between the low and high side gauges and settle at ~70PSI or so
5) At this point, CLOSE the low and high side manifold valve
5) Turn on vehicle, and assuming the low side service port valve is the only thing open, the system should suck whatever is left in the low side hose
6) Close and remove the low side service valve

Thanks Viven….I may give this a final shot today.

As I understand adding the oil, I should pull a vaccuum and suck the oil through the high side.  i am thinking of adding 3oz.  

Then, I will let it sit for a while and see if the dials note a leak.  If not, back to a couple bottles of refrigerant.  I will apply the manifold steps you suggest.  

Does this sound right?

[AmericanSavage]

FUZZFACE2 suggested I try one more charge, so i did.  Low side reading is shown, but wound up at 60.  High side I forgot to get on camera, but wound up around 250.

You can get a sense of the sound of the clacking of the compressor here.  BUT after I added 2oz of PAG 46, it quieted down a lot.  Still, I think the front seal is leaking.  Will know more tomorrow.

[viven44]

Oil and refrigerant should always be added on the low side (Suction side). High side would not even take in the charge.

[viven44]

60 on the low side is very high. It should be no higher than 50 unless it was middle of summer 110C.

Good luck!! Hope the charge holds.

[grumpin]

When you are servicing or even checking the pressure, do you have high and low side open to the gauges?

[AmericanSavage]

Grumpin got me thinking:  Did i set up the gauges right for a diagnostic reading yesterday?  The answer is NO, I concluded.  So, I went out this morning and did it properly.  About 40ish on the low, 150 on the high.  Vid shows it all for the most part.  I think I am in spec here.

Charge held.  Cooling ran me out of the truck this morning.  So far so good.  We shall see over the next few days whether it held.  Adding the oil really helped quiet things down, but it is still a noisy beast to my liking.

Really, thanks to all here, and FUZZFACE2 for the advice to give it one more try on another site.  Let’s hope it holds.

[grumpin]

Good to hear, hope it holds up!

[viven44]

Good call, I hadn’t considered that possibility. In normal use I have never seen the low side go up to 60, unless the compressor is not running and pressure is equalized.

The gauges and all its valves and not very intuitive, especially the  valves on the manifold gauge itself. It is easy to confuse them as the means to get the gauge to read when all those valves control is charging, and disconnect.

The low side manifold value should only be open when used to charge

The high slide manifold valve should only be open to recover the gases on the high side hose upon disconnecting, but very carefully ensuring things are not open to the atmosphere ever

[Danny G]

A lot of companies will evac and recharge the AC for $100. If it even has refrigerant left in it. My brother in laws machine measures what comes out test the system and then you pick the amount needed and it does it all.

Last AC I did was already dry. I did the replacement, pulled a vacuum to ensure it was holding then had him charge it up.

Before that I in my explorer I went to a shop like Midas and they evac'd the system. I went home and changed my compressor etc. came back they serviced it, charged me nothing for the refrigerant because they put back exactly what they took

[viven44]

I just looked at the manual for something. It is calling for 10~11oz actually for these compressors. (Tecumseh or York). I am not sure what type of compressor yours is.

If the compressor is still noisy, you can consider adding one (or maybe 2) of these cans! And these are easy as you don't need to hook up the manifold gauge. Just need one of those recharge hook-up deals that only hook up on the lowside.

https://www.autozone.com/cooling-heating-and-climate-control/a-c-system-oil/p/a-c-certified-pro-pag-46-oil-charge-3oz/424620_0_0?spps.s=5803&cmpid=LIA:US:EN:AD:NL:1000000:GEN:19502231967&&CATARGETID=120054150001286444&CADevice=c&gad_source=1&gclid=CjwKCAjwjqWzBhAqEiwAQmtgT3-n5pBAW7P9oK8H61W0hVfDfvICZ42qe0KVk1sZ1dHlc7kuUQA2thoCF18QAvD_BwE&gclsrc=aw.ds

[AmericanSavage]

Update:  After spending time on blend door repair (see other thread) Turned on truck today after 3 days….a/c is back to shutting off and on without cooling.  I had two solid days of it working as expected, then the 3 days for the blend door. There has to be a leak.  Also note that the sniffer does not work well.  

So I shall resort to dye at some point I think.

[AmericanSavage]

These are the days of our A/C lives……

So got the dye and a can of refrigerant today.  Not even 1/3 of a can and the compressor kicked on and did not stop.  Blew cold cold air the entire time.   All the appropriate hose lines and accumulator immediately started sweating as soon as I put the can to fill through the manifold gauge suction side.

Did a prelim check and I see no glow anywhere.  Will check again at dusk/night.

So obviously I am holding a charge to some extent.  

I have no idea what gives.  The new can with the dye would be can 6, which seems like alot to me if I am not leaking.

I also added an oring to the caps:  checked for glow an hour later, nothing.

Will check with light tonight and update.

[Gary Lewis]

You are making progress.  The pressures are the key, but you have to get the compressor to come on to check them.  Hopefully you won't have a leak.  

[AmericanSavage]

Found it!


…or at least one, but I definitely found a problem—could not really see it until dark last night.  There is a slight ever so slight leak at one of the lines made for me.  I could see the oil slowly coming out, and the dye lit up that area of the line.  I did not get a pic until this morning—I should have gotten a pic plast night, but anyway, here is the pic.

Off to the A/C line guy today.

[Gary Lewis]

Well done!  It looks like they over crimped it and cracked the metal.

[viven44]

Nice work!!

I have just kept the stock hoses on just about all conversions, and they work just fine. There is some theory about the molecular size of R134a being smaller than R12, but it definitely sounds like the stock Ford hoses have sufficient margin to accommodate R134a.

Vintage air also sells flexible bendable lines on all different sizes (#6 through #12, male to female, vice versa) that can help you adapt any given hose to your application.

Did you pull vacuum and verify that it held for 30 mins at least ? Just for my curiosity on whether vacuum test would pick up something like this.

[AmericanSavage]

Got the offending hose off, and underneath it is a horror show: