Thread: AC is weak on 72 monte carlo, any ideas?

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I have a 1972 big block monte carlo that runs the r-134 refridgerant. The outflow temp is cool but not extremely cold but I think the real problem is the fact that the airflow on max high is not very powerful.I checked the hoses underneath the dash and none seem to be leaking. Maybe i am just used to my toyota mini van fan that blows quite forcefully. Thanks for any help.

Maybe its time for a new blower.sweet car got any picks

i'll give it a try. no pics yet. i need to take some. thanks big truck

Did the A/C work well before with the same fan speed? The first thing I would expect to be the culprit is a low refrigerant level. A lot of the R134a bottles you can buy have half-ass gauges attached that can give you a good idea if the system is properly charged or not. Refrigerant is odorless and colorless and a gas at atmospheric pressure so a leak would be hard to notice and not limited inside the passenger compartment. Something else to look at is the condenser. Just like a radiator if it is clogged with dirt debris airflow will be limited and efficiency will drop. Same goes for the evaporator. Being the cold part of the system in humid weather the evaporator can turn itself into a block of ice. A poor blower could also cause problems here. Another thing is that when the A/C compressor is engaged the engine fan should be too, cause if you ain’t moving or you’re moving at a slow rate then there won't be much airflow through the condenser to transfer heat. Beyond these things you would need to crack open the system in order to make a repair. So I suggest taking it to a shop and have a tech mess with it, since there are expensive specialty tools and strict EPA laws, as well as a knowledge base most average car guys (or tech's for that matter) have not acquired.
Either way if the blower sucks replacing it with a better one wouldn’t be a bad idea.

My '82 Camino had poor air flow, there was a mouse nest in the duct in front of the core. Check your Monte for something like that before spending much cash.

I'll give all of these a try, thanks

low refrigerant is always the first suspect, but there are other things to check first: look to see that the condenser is clean, and does not have a bunch of folded or multilated fins. After that, check the volume of airflow from the vents. If it is low, you might have leaves or other trash in the evaporator.