Can I test a R12 system with R134a for a few minutes?

[Charrie]

That is an interesting idea Cusser! I do have an empty aluminum oxygen bottle that I could probably adapt.
These HVAC guys around my area must be very clean. I went by 2 shops and called 3 but none had any empty cylinders laying around.

So i found a guy who said he could recover the refrigerant but wanted to charge me more to get it back then I can buy a can for. Apparently he sells it to some company. I seem to have misplaced a can somewhere. Since i used one of my 14oz cans trying to add to the system this year, that led me one short unless I can find the hidden one!
A tip I learned about using a side can tap tool. I have Robinair side tap tool and had it sitting on the upper radiator support. Well it fell and hit the ground and the handle released! I now put a little electrical tape around the end of the handle after it is locked in place.

I think the next part of this job is to pull the orifice tube, dump the compressor oil, and accumulator oil to see what it looks like?

I do not have the compressor, accumulator, or orifice valve right now and it will be a couple of weeks before I do. So i am thinking maybe I could open the system to check the oil and orifice tube condition and then put the system back together minus the oil and orifice tube and pull a vacuum on the system to keep anything from corroding?
Just thinking if the oil doesn't seem burnt or contaminated and the orifice screen is pretty clear, would I need to flush the system?

As to recharging with small cans. I have read that is a very inaccurate way to charge a system.
I am going to get a yellow jacket short cut off valve that goes on the end of the manifold hose so when changing cans, I wont loose all the refrigerant in the hoses.
I weighed and recorded the weight of an empty 140z can and again with the side can tap tool on it and then a full can and the side tap tool. So now I know that the net weight of the cans I have is 14 liquid ounces. The charge is supposed to be 3.5 lbs which I calculate to 56 ounces.
The chart shows the charge needs to be 3-1/2 + .25-0. So how many ounces would be left in the manifold gauge hoses? Because 4-14oz cans = 56 ounces. Will the amount in the hoses be that critical?

[tbirdtbird]

No, won't be that critical. But remember, if the comp was running when you charged, you bleed the high side hose (red) back into the system thru the blue hose when you are done. That way you only have a puff of vapor in each hose, which counts for nothing. Those shut-offs at the ends of the hoses are very handy, I have them on all my hoses.

Post good pics of OT when you get it out, and before you close everything back up. Letting the system stand with a vacuum sounds like a good idea, but if a leak should develop, atmospheric air (think moisture) will be pulled in. Better to evacuate and then puff in a small amt of refrigerant (say up to about 5 psi) while you wait for the next step. Won't take much.

You would still need to pull a good vacuum (hr at least) once you have replaced whatever you decide before you re-charge, obviously

Submerge your cans in a basin of hot water to get all the charge out, else some will remain behind.

[Charrie]

Thanks!
so were back to the R134 question.. You said: Better to evacuate and then puff in a small amt of refrigerant (say up to about 5 psi) while you wait for the next step. I can't use the R12 to do that because it has to come back out and I only have just enough to charge the system with. Can the 5 psi be done with R134?
Maybe I should just wait until I have the compressor, orifice tube, and accumulator and try to get it done in a couple of days. i say a couple of days because I want to post pics of the Of tube and oil..

As to the accumulator, is there a r12 and a R134a one? It seems like there was when I bought the last one.

Compressor oil, IF it is determined that I don't need to flush the system, how much oil do I use? I believe I am supposed to drain the old accumulator and measure the oil in it and that is how much to put in the new one.. Same with the compressor, drain and measure the oil in the old compressor and add the same to the new one. Do I need to add any extra for what might have leaked out from the bad seal or when the refrigerant was removed or perhaps what did not come out of the compressor?
I just noticed the tag that came with the Motorcraft E6CH compressor that I used says to measure the oil lin the accumulator and add 2 more ounces.



I am going tgo send a message to Tim and see if he has a E6DH compressor W/clutch. I measured and it is a 5" pulley. I am not sure what the difference is in the compressors but i remember all the specs said that the E6DH compressor is an FS6 "style" compressor. The FS^ compressor is ear mounted and has 4 ports on top while the E6DH is tangent mounted and only has 2 ports on top. On the Ackits website it calls both type compressors FS6?

Thanks
Charrie

One more question. I was never impressed with the temps when everything was replaced new. Does the brand evaporator make a difference? I think the one I used was from 4seasons. Also I used an orange orifice tube and have read severalpeople recommend using a red one for better efficiency in hot temps. The van is a pretty big box for just the front AC. The best I ever got was 45F before the engine warmed up and then the temp would go up to 55F. I plan on installing a heater valve as it doesn't have one now.

[tbirdtbird]

Your method of measure what you got out and put the same amount back in is correct. As far as any lost due to the seal, add 1 extra ounce. (This is a total guess, it always is). . Be sure to rotate the compressor shaft by hand about 10 times to get all the oil out for a good measurement. I would install fresh oil, not the used stuff.
Do not use any 134 here at all. You are cutting it close with the way you have your R12 supply set up. Might be worth looking on eBay and getting another backup can of R12. It is still out there.
It would be better to do everything at once. If you want to dismantle partially and the vac down until the new parts come in, then only vac down to about 10" of vacuum, that way if there should be a leak, a whole lot of moisture won't be drawn in. But I'd wait till I had everything. Just be sure everything is capped off

[Cusser]

Does the brand evaporator make a difference?

Could.

I know on my 1988 Mazda truck I used an aftermarket brass/copper evaporator and the factory replacement evaporator was aluminum and a different design. But money was tight 2 decades ago, and Mazda evaporator was over twice the price and not available for a few days, plus two trips to the dealer (to pay/order and to pick up). But my memory seems to think that the vent temperatures were a little colder with the factory evaporator.

[Charrie]

Thanks for the replies!
I am going to wait and do everything at once. The only issue might be if I find anything inside once I open the system. If not then it should be good to go (I think).
I went a head and ordered 2 more 14oz cans of R12 so I will have a spare in case I accidentally loose some.

The specs call for a orange orifice tube. What do you guys think about my using a red one? Only going by what I have read, the red one is supposed to give a little better performance in hotter climates above 105F It stays close to 100 in the back of the van with just the front ac on while 55F is coming out the vents.

Also last time I used a New YC-53 Motorcraft compressor. I ordered one and I cold not get the shaft to rotate by hand. I had to put the compressor in a vice and then use a tool to break it free. I returned that compressor and they sent me another. After the second compressor came that way, I was told that when a compressor sits on the shelf for years, the assembly lube used when putting it together dries up and causes this problem but that it is just a matter of breaking it loose. Though I would like to use a Motorcraft brand compressor on my old Ford, I am not sure it would be wise do to. Being old may also be why the front seal failed in 6 years. I remember after breading it free, it took quite a few rotations with a drill before the compressor rotated smooth by hand.

Also I keep reading that there are 2 different accumulators. one for R12 and another for R134a. the desiccant bag is different in each one?

Thanks
Charrie

[tbirdtbird]

Seals do dry up on the shelf. Have had it happen with front and rear main engine seals for cars where the seals sat on the shelf for 10 yrs. And as such they are no longer any good. And to me you should not have so much trouble getting the shaft to turn. Don't like the sound of it .
Is there not a modern fresh compressor available that will fit? Does it HAVE to be Motorcraft?

[Charrie]

No it doesn't have to be a Motorcraft compressor, I just try to make it policy to replace all the parts with Ford or Motorcraft. The ac evaporator and high side hose off the condenser are the only two items that are not Ford or Motorcraft on the whole van. I understand a newer more recent manufactured compressor should turn freely and have good seals. I will ask Tim a bit more about his compressors such as where do they come from and what is the warranty.
Thanks
Charrie

[Tim]

The Four-Season compressor link you sent was not a Motorcraft compressor.

People get hooked on OE brands. Aftermarket compressors are not the issue. It's how repairs are done that plays a bigger factor. But of course, an improper procedure is done. It will always be the compressor's fault.

Like playing with Orifice tube colors instead of upgrading the condenser to a true parallel flow model. And yes, they don't make a drop-in for your vehicle so you have to make custom hoses. It's work but it is the correct way to do a conversion and repair that will last.

[Charrie]

Thanks for the reply
Yc-53 or E7VY-19703-A is the original E6DH Ford part number and there are 5 listed at the link below

There is one listed below for $175 but without a clutch
Deleted Ebay Link.

I sent you the link to the NEW Four Seasons brand because I was already thinking it would be better to buy a newer compressor so that the seals would be in good shape. I would not expect you to try to match prices with OD or NOS from Ebay or other companies.

I am not going to do the conversion to R134a and so it is my understanding that the original Tube/Fin condenser should work ok with the R12. AS you know there is no replacement Tube/Fin condensers available right now. Mine is only 6 years old. If the OT is clean and clear as well as the oil, then that would be a good indication that the only issue I have is that the front compressor seal is leaking and the system is low on refrigerant.

I used the orange OT last time and that if what I will be going with this time. I was just asking opinions.

This system has lasted 6 years since I put it together back in 2016 and wold still be working if I t hadn't been for a compressor seal leak. My intention is to put this pack together so that it will last at least another 6 years or more. That is why I am here at the forum asking questions.

Thank you
Charrie