Is their a way to check the refridgerent level with out using gauges? On some cars I have seen a little "sight glass" on the dryer filter. If you saw bubbles in it you needed to add refridgeerent. Does the Max have one of these?

Or can I just buy one of those do it your self kits and put a can or so in the system?

Its getting hot now and I want to be sure the AC is working at 100% efficiancy?

 

Even if it does have the bubble "sight glass" I would not rely on it because it is not near as accurate as gauges. The slightest amount of psi can make all the difference.

One way you can ensure your system is operating at full effeciency is make sure your condensor (front end/not the radiator) is clean and if its not you can buy a cleaner from a A/C shop that works very well.

You can check for leaks in the engine bay by looking at the refrigerant lines where they have connections. Look to see if you see ANY dirt/oily/grease present at these connections. If you do, you most likely have a refrigerant leak which would need to be FIXED first. This may require the system to be drained first and then get it reserviced.

 

So what kind of pressures am I looking for. I have seen the gauges used, so I'm vaugly famalier with them. How much do they cost?

 

Unfortunately it is not a cut and dry answer as far as pressures are concerned. Too many variables play a part to achieve the correct amount. Temperature, humidity and even altitude play parts. I would not even give the "shade tree" answers because too much pressure will cause premature failure of the compressor and not enough won,t cool properly. It would really be a good idea to find a local garage that is trustworthy to just check it. In my opinion though if it seems to cool well or comfortable then I would not worry about it. The best thing you could do for the A/C is to check the cleanliness of the condensor. To give an example, a friends house unit was not cooling at all. The low pressure side was reading higher than the high side pressure all because both the condensor (outside) and evaprator (inside/A coils) were very dirty. They were cleaned and all was good. If this seems foreign to you or you have any doubt about this PLEASE DO NOT try this yourself. You could hurt yourself or damage your system. Hope this helps.

 

David Haygood (dch95) suggested you let the professionals handle this job. He's right.

To answer your questions... the pressures are dependent on ambient temperature. There is no fixed number, you read the pressures off a graph. The gauge sets are fairly expensive. One example: Harbor Freight #39248, $90 + handling. http://www.harborfreight.com/cpi/taf...emnumber=39248

 

I found some auto AC info on the WEB. SO I think I understand whats going on. I have seen the gauges used before on may ocasions by an old fried who doesnt have them anymore. I feel comfortable with the procedures.

The problem is, on a HOT day 90F & 95%humidity it wont cool when the car is in stop and go traffic, even after driving for a bit. When I get up to speed it cools fine. When I go back to idle it cant hang. Ive had the car for two previous summers and it worked just fine.

I checked the electric fans and they come on with the AC.
I did have a cloged evaporator water drain and I fixed that.
I'll clean the condensor with some 409 and a long bristle brush tonight.
I'm also going the return line to see if it is sweating or not, I bet at idle it's not.
Hmmm, I put on my UDP this winter, perhaps thats a problem. But before I go that route I want to check all other options.

Looks like I need to get some gauges.

Thanks for the help...

 

Usaully it,s been my experience that if at idle it won,t cool but at high speed it will, usually means that you are losing freon. If that is the case it needs to be fixed BEFORE you service it because you will just lose what you put in it. Freon does not get consumed in the cooling process therefor you would be throwing money away to service it.

UDP may have some effect on this but since I do not have one I can,t testify as to where or not it will.

 

The UnderDrive Pulley is a factor. It turns the accessories at what, 25% slower speed?

Try this simple experiment. Sit in the car and hold the engine at 950 rpm for five minutes. This will spin the A/C compressor at about the same rpm as it was turned by the stock pulley at a 750 rpm idle. Now evaluate the performance of the A/C. If you judge it to be cold enough, the spotlight of suspicion falls on the UDP. If not, you may be losing refrigerant.

 

Good idea! Ive got the idle set to about 850 or so now, I'll turn it up to 1k and see what I get.

I read that you can take some soapy water and spray it on the connections. Or buy a $150 leak detector. Or take it to a shop...

 

Chances are the leak is so slow that soapy water would not show up very well. A/C shops use a freon "sniffer" to find out where it is coming from. That would be the better way to find a leak.