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DISCUSSION => Engine + Driveline => Topic started by: FL318is on June 20, 2007, 08:52:34 AM

Title: A/C problem, need help!
Post by: FL318is on June 20, 2007, 08:52:34 AM

Well the humidity is here along with the afternoon heat, so it seems only fair that my a/c should act up.

The symptoms are; it blows a/c cool for awhile and then just blows.  I shut it down for about 3-4 mins and it blows cool again.

Is it a freon charge or something more sinister?  Follow up question, what freon do the M42s take and can I buy it from an auto supply house.

Its too dang hot down heah!:(

Title: A/C problem, need help!
Post by: Vladi on June 20, 2007, 09:34:24 AM

You've got either R12 or R134A coolant. There should be a label somewhere in the engine bay.

Title: A/C problem, need help!
Post by: FL318is on June 20, 2007, 12:16:38 PM

I was wondering if it could be Evap Temp Sensor?

Title: A/C problem, need help!
Post by: dino245 on June 20, 2007, 12:44:41 PM

sounds like your evaporator is icing up or you receiver dryer is freezing.

Title: A/C problem, need help!
Post by: FL318is on June 20, 2007, 01:42:55 PM

Quote from: dino245;28136

sounds like your evaporator is icing up or you receiver dryer is freezing.

Solution?

Title: A/C problem, need help!
Post by: gearheadE30 on June 20, 2007, 03:31:45 PM

Generally a refrigerant recharge will fix this. Also, make sure that the evaporator drain (do we have one?) isn't clogged. This caused problems on a friend's car awhile back.

Title: A/C problem, need help!
Post by: Shocker on June 20, 2007, 11:16:50 PM

Quote from: FL318is;28124

Well the humidity is here along with the afternoon heat, so it seems only fair that my a/c should act up.

The symptoms are; it blows a/c cool for awhile and then just blows.  I shut it down for about 3-4 mins and it blows cool again.

Is it a freon charge or something more sinister?  Follow up question, what freon do the M42s take and can I buy it from an auto supply house.

Its too dang hot down heah!:(

Is your AUX fan working?   If there’s little to no air blowing across your condenser your A/C won’t work very well, regardless of how much Freon you have.

Title: A/C problem, need help!
Post by: FL318is on June 21, 2007, 08:03:17 AM

Quote from: Shocker;28179

Is your AUX fan working?   If there’s little to no air blowing across your condenser your A/C won’t work very well, regardless of how much Freon you have.

This is a really bad question but, where is the AUX fan?

Generally a refrigerant recharge will fix this. Also, make sure that the evaporator drain (do we have one?) isn't clogged. This caused problems on a friend's car awhile back.

I hope this is all it is.  Where would I find label for the particular freon needed?

Title: A/C problem, need help!
Post by: ak96ss on June 21, 2007, 08:25:45 AM

The aux fan is in front of the radiator, directly behind the kidneys. IMO, the easiest way to get to it is to take the front end off, but that's me...

Title: A/C problem, need help!
Post by: Wizard on June 21, 2007, 11:43:48 AM

YOU WUSS.....It's not that hot out yet......lol

Usually even if you aux fan is not working, driving on the highway (at speed) will usually keep enough air blowing over the evaporator to keep the A/C system working somewhat. Having the aux fan working is better though.

Title: A/C problem, need help!
Post by: gearheadE30 on June 21, 2007, 03:01:58 PM

My aux fan doesn't hardly ever turn on and the AC works fine, so i dunno.

BTW these cars came with R12, although some have been converted to R134a.

Title: A/C problem, need help!
Post by: FL318is on June 21, 2007, 11:06:41 PM

Well now that I have located the AUX fan (duhh) I discovered it was not rotating.  I believe there might be a switch that shuts it on and off.  When I get the chance (traffic sux) I will get it up to speed and see if it blows cold.

Wizard, you live south in the tropics LOL!

Title: A/C problem, need help!
Post by: Shocker on June 22, 2007, 06:06:18 PM

Quote from: FL318is;28243

Well now that I have located the AUX fan (duhh) I discovered it was not rotating.  I believe there might be a switch that shuts it on and off.  When I get the chance (traffic sux) I will get it up to speed and see if it blows cold.

Wizard, you live south in the tropics LOL!

It's probably your low speed resistor for the Aux fan.  Dose the fan spin smooth by hand?

Title: A/C problem, need help!
Post by: Wizard on June 23, 2007, 09:00:23 AM

It could also be your temperature switch in the side of the radiator that is bad. My aux fan wouldn't come on also. To see if the switch is bad you can "jump" the connections. Unplug the connector. Turn on the A/C and jump 2 of the "prongs" on the connector (it has 3 but I can not remember which 2 at the moment...Don't worry, you cant hurt anything). The AUX fan should come on if it is working. I actually have mine "hot wired" this way. I by-passed the temp switch. The only bad thing is the the aux fan will never come on unless the A/C is on. Haven't had a problem yet though with car overheating.

Title: A/C problem, need help!
Post by: FL318is on July 08, 2007, 12:25:44 PM

Quote from: Shocker;28289

It's probably your low speed resistor for the Aux fan.  Dose the fan spin smooth by hand?

Back home after a last minute change in plans.  BIG thanks to oldtimer, but more on that later.

Yes, the fan spins smoothly by hand.  I also "jumped the prongs but no results.  I will give it another try later.

Its HOT!:(