Getting warm..time for my first A/C Question

**sirfoulsalot** · 03-28-2007, 09:34 AM

Hello again..
My a/c doesnt seem to be working properly.
It blows cold when cruising on the highway,,but sitting still or in traffic it stops blowing cold air and actually starts blowing warm air.
Checked with a gauge,,freon is at proper level.
Its a 1995 Burban R-134
Any ideas?
Thanks..Randy

**MrShorty** · 03-28-2007, 11:14 AM

How is your airflow through the condenser? If the condenser fins are plugged with enough bugs/dirt/leaves/etc., there won't be enough airflow through the condenser to effectively remove the heat and condense the refrigerant. Is your fan clutch working properly?

**TrailLeadr** · 03-28-2007, 11:30 AM

Originally Posted by MrShorty

How is your airflow through the condenser? If the condenser fins are plugged with enough bugs/dirt/leaves/etc., there won't be enough airflow through the condenser to effectively remove the heat and condense the refrigerant.

Good point

**unplugged** · 03-28-2007, 11:49 PM

Is the heater valve closing completely? Try this: At idle, turn off the AC and see what temp the air is coming out of the vents. Temps above ambient air temp could indicate the heater is contributing to the problem.

**sirfoulsalot** · 03-29-2007, 09:29 AM

Okay,,sounds like great advice.
How can I check to see if the fan clutch is working properly?

Unplugged,,I will try your idea later today.
Thanks,,Randy

**Dr_Zero** · 03-29-2007, 09:58 AM

Originally Posted by sirfoulsalot

Okay,,sounds like great advice.
How can I check to see if the fan clutch is working properly?

Unplugged,,I will try your idea later today.
Thanks,,Randy

I am getting my clutch fan replaced as we speak and so I did some looking around before I did and found this.
http://www.haydenauto.com/installation/faqs.htm

On a side note Imperial brand clutch fans are just repackaged Hayden now and cost more! and Hayden and Imperial are part of Four Seasons another name in fans.

I called them to check after seeing both catalogs on the web site and they said the Imperial was repacked Hayden sold by Advance Auto.

Q. How do I know if my fan clutch needs to be replaced?

A. These are the most common symptoms of a failed fan clutch:

* Leaking fluid - Oily build up around the bearing or thermal spring.
* Bad bearing - Seized, turns rough or has excessive play, (more than 1/4" at fan tip).
* Worn thermal spring - Spring is loose.

Some fan clutches will show no visible indication of a problem yet may still be faulty. The following may also indicate a faulty fan clutch:

* Fan spins excessively - Three or more times when hot engine is shut off.
* Poor air conditioning - At low speed or excessive high side pressures.
* Doesn't engage - Fan speed does not increase or "locks up" when the engine is hot.
* Does not disengage - Fan clutch won't slow down when the engine is cold.

**sirfoulsalot** · 03-30-2007, 10:14 AM

DrZero...
Thanks alot!
Very informative.
Are you going to change your water pump too?

**Dr_Zero** · 04-02-2007, 07:24 AM

Originally Posted by sirfoulsalot

DrZero...
Thanks alot!
Very informative.
Are you going to change your water pump too?

Yes! the water pump is what lead me to get a new fan clutch LOL It died and when talking to the mechanic he showed me how mine has slowed, I had not really noticed.

I think the fan helped to add to the demise of the pump as more stress on the pump bearings caused them to fail sooner.

**84fiero123** · 04-02-2007, 08:27 AM

I don’t know a lot about this, but wonder does anyone on here?

Is a clutch fan really needed?

I mean why not change over to a regular fan?

Other than making the engine run cooler, would it affect other controls, like the rich settings on the fuel injectors ?

**TrailLeadr** · 04-02-2007, 08:46 AM

Originally Posted by 84fiero123

I don’t know a lot about this, but wonder does anyone on here?

Is a clutch fan really needed?

I mean why not change over to a regular fan?

Other than making the engine run cooler, would it affect other controls, like the rich settings on the fuel injectors ?

I think the purpose of the clutch fan was similar to the intermittent AC compressor. Just to help make the engine more economical, save some hp.
Fan running continuously would not only help the engine stay cooler, but would also tend to make it much louder.
I have a neighbor who drives a early 90's jimmy/blazer. His clutch is stuck on, so even in the coldest months of winter his fan is running with the engine. When he drives by it sounds like one of those boats they use out on the everglades. Like a huricane fan. It actually drowns out the noisy diesel engines.

A nice quiet radiator mounted electric fan is pretty much the way to go IMO.