When my wife's 84 300TD A/C is on, the cold air flows out of all the vents plus thru the vents near your feet. On my 78, this is not the case! I have no vacuum leaks and everything seems to be working fine but..... We were low on R12 so my neighbor had an extra can from his recent trip from Mexico. The stuff there is around $8.00 a can!! We put the can in and the air is now cold but... immediately the clutch started to knock!! The next morning I took it to an A/C mech. and when I tried to turn on the A/C the clutch did not go on. He got under the car and wrapped the clutch with his flashlight and it turned on. He said that the gap is wide on the clutch and it may or may not be adjustable. Since the time he hit the clutch it now works. I talked to my mech. and he said that the clutch may go out at anytime and that the compressor may freeze up taking all the belts with it! We are about to go on a 3k mile trip with four kids and the dog soooo I want the A/C to work. My mech suggests to get a new compressor and clutch ($330.) and rec/dryer and exp.val. and convert it all over to R134. I did this to my 78 300d and it works great. Sorry for the verbage and thanks for the help!!

hey greg

I'm just curious though, but how did you convert your R12 system to R134? and was it really hard to do? I'm actually interested in doing this my self but I'm having problems with my cooling system. it would be great if you could tell me the major parts that needed to be replace in order modify R12 to R134

thanks greg
allan

Hello Allan,

The change was done on my 78 300d. The compressor was bad so I had to replace it with a new one along with a new rec./dryer and expansion valve which is located behind the glove box. All was simple except for the removal of the York compresson which on this year is located on the top left side of the engine. You have to take off a lot of things inorder to get it off. The new York came with the different oil for the R134. No hoses were changed and it works great. If your compressor is O.K. all you have to do is change the oil to work with the R134. I did a lot of research and got a lot of different info from almost everyone. Some say the pressure is higher on the R134. I found this not to be true for at least on my car. The fitting that allows the gas to enter the system had to be change... I believe so... It cools down just fine now. Thanks Gregg

hey greg,

very interesting....i was thinkin that you had to change the whole entire A/C system...(I.E new control unit, hoses,etc.). How is your temperature when you blast up your A/C? does it cool better than the original R12 or is it the same?

thanks for your replies
Allan