so i am compiling anything and everything i can for a ac rebuild so i can do a write up on the subject to help everyone so please add any tips and tricks you can. i will do a step by step with pictures after i get comments

thanks all

 

first question do you need to change the orifice tube in a r-12 to 134a conversion? and does anyone have tips or tricks on that?

 

The orifice tube is $2 so it's just smart to change it, especially since it's usually clogged with crap.

 

as Sean said its good to do if you have to crack the system open... but no you do not

 

Fun fun fun... rebuilding the AC.... Words of advice... don't cut corners... go back with OEM or good quality everywhere you can if replacing stuff..

Office tubes are different colors for r12 and 134 systems.

I had to rip out the entire pile of crap the PO had put in. I went back with a motorcraft compressor and spectra condenser/evaporator, new hoses throughout. New drier and low pressure switch. I have not been sorry... works great and will freeze you out.

 

Mine worked for two weeks with a new compressor. It needs the evaporator.

 

My evaporator was a PITA. Getting the freakin thing back in. It would be a whole easier without the engine there. Its wasn't that bad of a job, I just had to jack with it for a couple hours to figure out how to get it to lay in there with the space I had.

 

I've retrofitted many r12 systems without changing the orifice...low side pressure makes more difference than the orifice does...

you should also change the low limit switch to one matching r134a but i never did that either... a simple dump and fill and down the road...10 years later they are still running.

 

thanks for the advice so far i am getting all the parts together and will be redoing all of it. i just see questions all the time for ac and want to make one place to answer questions for all as of now mine is working out fine putting out 45 degree air but i do have a slow leak so im going to start from scratch - the compressor it is less then a year old. but please bring on the tips and tricks. it is on hold for a min my window motor went out this morning