ac blows cold then hot

NickD

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Mechanical high pressure switches were common back then if you don't mine back then. Today, using a thermistor plugged into a BCM to kill the compressor if the high pressure, actually a proportional temperature sensor fed into a BCM to cut off the compressor clutch.

Latest compressors are electrically controlled variable displacement that are like the good old days where they run continuously with switched on. Sure saves wear and tear on both the drive belt, compressor, and clutch. With an engine running at least 2,500 rpm, that clutch and compressor would have to accelerate from zero to running speed in no time flat. Lots of stress. AC's only know two operating states, dead off or full on. Usually the cycling switch was the first to go, and since it was in the refrigerant circuit, that had to be recovered first.

Ha, still say, automotive should advertise if you want problems we have problems, but some of us made a good living because of this.
 

nickb2

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I made metal caps with O-ring to seal the ports. So far, so good...
I would love to see how you made thoses, do you have pics question mark cuz my keyboard for some reason still refuses to switch to english ÉÉÉÉÉÉÉÉ
 

nickb2

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but some of us made a good living because of this.
Still am, but it doesnt make it right.

I refuse to work for A GUY who asks or even worse TELLs me to screw the screw.

Aint gonna happen not in my value system.

I make a good living cuz I am some what good at what I do and know how to grab my balls when it time.
 

NickD

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Did find chrome plated brass with neoprene seal inside for my tire valves, these would fit on an R-12 system, hexed shape so could use a wrench.

One port is an non-standard Acme thread of 1/2"-18, standard 1/2" threads are either 13 or 20 TPI

Special tooling is required, could turn them on a lathe if your lathe has an infinite number of thread sizes. Mine has different gears for English or metric threads.

Just better off to purchase metal caps with seals, here's one.

 

billr

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Did you bother to look at the link you posted? Those are metal covers over plastic caps; won't seal any better than the stock ones. I want metal functionality, not metal appearance.

I'll post a picture and brief description of what I made later today. Ignore all that FUD about the threads, none of it is correct for R134a ports and you don't need to cut threads anyway.
 

NickD

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I was tricked Bill, should report the seller, but a closer looked revealed aluminum coated plastic. In doing another search,many are having problems with R-134a ports leaking, even my quick connect air hose couplers leak like crazy. Who is to blame, EPA and SAE, but the EPA is super critical on refrigerant leaks so why did these idiots approve of these?

Their main goal was to change these ports form R-12 ports so no one would put R-12 in them, but not very likely, price of R-12 shot up from 25 cent a pound to like 80 bucks a pound.

First R-134a vehicle did not cool very well, like any new technology, took them about ten years to get it right. Now the EPA is claiming R-134a is causing global warming. Not around here, last winter had many -30*F winter days. My home air conditioner bill for last August was five bucks.


Found hundreds of metal service caps for R-12, but this is for pre-1994 vehicles.
 

nickb2

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Btw guys, just to say, very happy with the new parker high low adapters.

We just got them fitted on our r134r machine cuz it had developed a strange problem, when on vacuum, would suck oil out of jar. So I pronto went see boss, we got a bad machine. Apprentice dint like the fitting adapters, he felt they were wobbly and such, so we wanted something better, we got the parker ones. They are really nice and snug and you can see the machine process in these.

I told apprentice, when did you observe we just sent out a weeks worth of possibly still leaking cars and the comebacks that will ensue.

Well. to day a toy tacoma, last week, put in a condensor, not me, him, didn;t heed advice, client did two days of ac and dead.

I must say, if this is your day job, this hundred is well worth it. I felt it right on the first go with em.

Oh, we got a new vac pump and a new ream from boss for all this cost.
I went outside and smoked a smoke while reaming was in force. ;)

 

nickb2

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BTW, thats a hundred per coupling. But well worth it.

The robinair guy said the solenoid that tricks the unit to inhale uv pag whatever,was fine, but the valve was stuck partially closed, hence vac was not at all on par to deliver a clean and proper diag. I am sorry I missed it, but sure know we pulled all the ac units we did since we found that prob in the robinair unit, boss is going to have to spread that one thin. ;)

Anyway, just the woes of ac when u do it on a nascar quick in quick out level.

I probably could have found that myself, but why bother when it is a unit parts of a reburish program.

Anyway, probably off topic, just sick of


Found hundreds of metal service caps for R-12, but this is for pre-1994 vehicles.

Just sick of this in our world. The thinking that actually brings growth.
 

billr

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"BTW, thats a hundred per coupling. But well worth it. "

You, too, read the link you posted. The $104 cdn is for a set consisting of both a high and low coupler
 

NickD

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A company I was working for 50 years ago wanted to make an engine compression tester with screw in fittings as opposed to using a neoprene cone. Those threads were non-standard like these R-134a threads, we had to pay a small fortune to have dies made for our automatic screw machines.

So Bill, care to share how you made yours?
 

billr

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See my other "A/C ports" thread.

As to the spark-plug threads, 14mm and 18mm were standard 50 years before your "50 years ago"; by the 1920s (maybe even before). Quality tooling for manufacturing tooling is never cheap, but those dies would certainly not have been "special" in 1969!
 

nickb2

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You, too, read the link you posted. The $104 cdn is for a set consisting of both a high and low coupler
yeah, I did read that wrong cuz I saw others ones cheaper. Sorry for typo, it is in fact for a SET of parkers.

Thx for the correction bill. But I used them again three times today, and still like the feel of the machining and the fit, you can tell these were not done in a fit of frenzy robotics.

As a joke, if I was paying for those couplers on the robinair, I may have caught that 50$ error. But since it is company, they can deal with that.

I love this site.
 

MrConspark

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Did find chrome plated brass with neoprene seal inside for my tire valves, these would fit on an R-12 system, hexed shape so could use a wrench.

One port is an non-standard Acme thread of 1/2"-18, standard 1/2" threads are either 13 or 20 TPI

Special tooling is required, could turn them on a lathe if your lathe has an infinite number of thread sizes. Mine has different gears for English or metric threads.

Just better off to purchase metal caps with seals, here's one.

Currently sold out- bugga. So they show the crap arse plastics ones that they have zillions of
 
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