134 Conversion Question

[Snakeyes_Tx]

I had a high pressure line explode on me about a week ago. I have since changed it out with a shiny new 1/2 line.

We're refilling the system now with the larger can of 134/Leak Seal/Oil and it took half of the typical smaller 134 charge cans.

The pressure readout is 300 psi at idle on the high side. Is this normal?? What's the limit?

Also, how much of 134 does our system take total?

[Sergio & Ulrike]

300psig is to high.

Did you pull a vacuum on the system prior to charging it? Air in the system will cause high discharge pressures.

Did you loose enough oil that you had to add more? To much is not good either.

The dealer or TSM manual may give the charge weight.

Hope this helps.

[andy d]

Snakeyes, the guys on the bmw board advise to use less r134 than you would r12

[Snakeyes_Tx]

Yes, yes, the R-134 is 90% of R-12 capacity. When the line blew, the valve cover was coated in oil. I went ahead and used the R134/Oil/Leak Seal can (its about twice the size of the typical 134 can), and then 134 charges. I pulled a vacuum on my system for well over half an hour. Did a leak-down test and it held vaccuum just fine.

The pressure reading was just a hair about 300psi AT IDLE! That can't be right huh? Any other ideas??

[Sergio & Ulrike]

When you switched from 12 to 134a did you change the filter/drier? (Not that this will cause high discharge pressures)

Is the condenser dirty/plugged? Good air flow across the condenser?

Over charged?

Hmmm.....still thinking

[Sergio & Ulrike]

http://www.aircondition.com also has a board you can post to if you dont get the answers here.

[Lindel]

You should have about 30 oz. of R-134a, no more. High side should be around 225, or so. Are you sure you are using R-134a gauges? The R-12 guages won't read quite right, with R-134a.

[Sergio & Ulrike]

I do not believe that is correct Lindel. The difference between the gauge sets is that the 134a set has a scale on the face to convert pressure to temperature for 134a and a R-12 set has R-22, 502 and 12 on its scale. X psig is X psig no matter the gauge set.

[ITLBOK333]

So what should a 134 gauge say when filled to the proper amount? I bought a new gauge/filler grip aparatis that works well, I filled mine till it was in the green but does that mean it s full for my 89 waggy? thanks all

[TexasJ10]

Considering that your original high pressure hose burst, it sounds like you have an obstruction in the line. My guess would be that something dislodged and is stuck in the expansion valve. It would be best to replace it if it is the blockage point. Lindels right about not exceeding 225 to 275. When it is real hot out the pressure will be higher. Did you flush, and back flush the system prior to installing the new hose and evacuating? You can flush these easily with mineral spirts and dried shop air. Some say to never use shop air, but I put one of those cheap harbor freight filter driers used with paint guns to get it dried out enough and haven't had a problem.

[steven79]

tx j1o did you see the date snake posted this? lol

[TexasJ10]

No I didn't. I wonder if he got it fixed yet! ;) ;) :eek: tongue.gif tongue.gif

How is Tulsa treating you?

[ August 19, 2004, 09:58 PM: Message edited by: TexasJ10 ]

[steven79]

ya i fixed it for him long ago, the wag is no longer with the liveing Glenntx parted it out after snake broke the second piston in it.
I love it up here, the weather is great this summer not to hot.and i found a chero i will probly get for a hundred bucks, it is only needing a motor. and i am also looking at a J10 for 250 bucks that needs a flex plate put in it.

[Lambrewski]

steven79 - have a buddy in Okemah (1/2 way to OKC) that has a 70's FSJ he's wanting to sell.e-mail me if you're interested.

[pb]

Originally posted by ITLBOK333:
So what should a 134 gauge say when filled to the proper amount? I bought a new gauge/filler grip aparatis that works well, I filled mine till it was in the green but does that mean it s full for my 89 waggy? thanks allIt should be. The gauges measure the amount by pressure. If it is within the specs on the gauges (green) and not exceeding the 225-275 stated above I think you should be fine. In terms of the 12 oz. cans, three would probably be the max on a r-12 converted vehicle.

[ITLBOK333]

thanks PB...