TheSamba.com :: View topic

Sun Jun 26, 2011 1:55 pm

I am trying to fix the AC on my 90 syncro westfalia. I recharged the system and it held for about a month so I looked at it with my buddy (neither one of us are mechanics) and we realized that the compressor was not working (the clutch was not engaging) so I took it do a local mechanic and had a new compressor installed. (I am hoping that the freon was leaking from the old compressor)
Now the AC works OK, but not great. I have a couple of questions.

1. When the auxiliary fan comes on the AC turns off, is that the normal setting? If son can it be adjusted/modified to stay on when the auxiliary fan comes on?

2. The mechanic did not replace the dryer, even though I brought one because he said that it was rusted in place and he didn't want to risk damage to the connections and/or hose while replacing it, my question is: Should I have him replace the dryer even if it means possible damage and replacing the hoses?

3. I read the blog about 'Red Tek', should I use it instead of the R-134 that the mechanic put in?

Thanks in advance,
Ray Strack

Sun Jun 26, 2011 2:12 pm

raystrack wrote: I am trying to fix the AC on my 90 syncro westfalia. I recharged the system and it held for about a month so I looked at it with my buddy (neither one of us are mechanics) and we realized that the compressor was not working (the clutch was not engaging) so I took it do a local mechanic and had a new compressor installed. (I am hoping that the freon was leaking from the old compressor)
Now the AC works OK, but not great. I have a couple of questions.

1. When the auxiliary fan comes on the AC turns off, is that the normal setting? If son can it be adjusted/modified to stay on when the auxiliary fan comes on?

2. The mechanic did not replace the dryer, even though I brought one because he said that it was rusted in place and he didn't want to risk damage to the connections and/or hose while replacing it, my question is: Should I have him replace the dryer even if it means possible damage and replacing the hoses?

3. I read the blog about 'Red Tek', should I use it instead of the R-134 that the mechanic put in?

Thanks in advance,
Ray Strack

I am by no means as good as most that do their own work on their vans on this site but I will tell you what I think and let those more wiser then me to chime in.

1. If they had to completely discharge your system (and they do to repalce your compressor) the mechanic should have replaced the dryer. It it at least the one thing that should be replaced after the system has been open to make sure there is no moisture.
2. If you are referring to the fan that cools your radiator, the way mine works is when I turn on the ac that fan comes on. I just walked in from outside after charging mine for the first time since I had it. (on a separate note do not allow your headlight plug touch the green fan resister because it will melt it, ask me how I know).
3. Did he pull a vaccum on the system to make sure there were no leaks? My bet is he did not if he was unwilling to replace the dryer, IMHO.
4. As far as the Redtek vs 134, you can read for hours the discussion on that and I will tell you if I ever drain the system and replace the coolant that is what I will use.
5. Has your condesor been flushed. From my understanding that is one of the best things you can do to make your ac perform at it's best.

I bought a book on vehicle ac systems and read it from front to back so I could understand how it works. You can get them cheap on ebay and I hope to become better at working on my ac systems in the future when I get a set of guages and a vaccum.

Chris

Sun Jun 26, 2011 2:35 pm

The rad fan should turn on low speed every time you turn on the A/C.

During A/C operation middle speed fan will at times be triggered by the freon high pressure switch.

If the radiator gets too hot, the rad high temp switch will trigger the high speed fan relay and at the same time disable the A/C compressor clutch.

It is common for the rad fan resistor to get cooked over the years and then one or both of the lower rad fan speeds may not work. The A/C will give reduced performance if the various speeds of the radiator fan are not working. If the lower speeds don't work, high speed will also be triggered far more often and the A/C compressor will shut off more often. On some vans a misguided person may have replaced the fan temp switch with one that runs the rad fan at very low temps and thus the high speed will be more frequently triggered and the A/C will be shutdown just when you want it most.

Mark

raystrack wrote: I am trying to fix the AC on my 90 syncro westfalia. ...................
Now the AC works OK, but not great. I have a couple of questions.

1. When the auxiliary fan comes on the AC turns off, is that the normal setting? If son can it be adjusted/modified to stay on when the auxiliary fan comes on?.................