Advice Needed: "Clogged Up A/C Ducts??"

[Road_Runner]

I finally got my 73 out of the shop.  The trans leak repair turned into 2 months in the shop rebuilding the trans, installing a shift kit & deep pan, new starter & battery cables, rebuilding the A/C with R134 freon running down some wiring issues....

A lot of this I was planning to do myself, but while they had it on the lift, what the heck.  So the trans is great, and the A/C blows cold EXCEPT the volume is way below normal.  I thought it was the fan that wasn't blowing except on low, but the repair shop tells me thats not it and that my duct work is clogged somehow.  They said they worked on it for a long time to blow as much as it does but to fix it completely they'd have to pull the dash out and that would be buku $$$$. 

Anbody else ever have this condition and if so were you able to fix it without pulling the dash out & dissassembling everything?  They mentioned theres a screen in there that can get clogged and I've noticed small bits of black foam gasket material being spit out the vents.  I thought about trying to hook up my shop vac to try to pull more of what's blocking things but am also looking for any advice that would lead me in the right direction.

It's awesome to have my Barracuda back finally, but with temps in the high 90's I need that A/C working!!

Later, Jim

[dutch]

I can`t think of anything that big in there to clog it up.  Maybe a vacuum hose that moves one of the valves in the heaterbox came off? If the box hasn`t been rebuilt, It`s not that surpising there`s some foam coming out every now & then.

[Road_Runner]

I can`t think of anything that big in there to clog it up.  Maybe a vacuum hose that moves one of the valves in the heaterbox came off? If the box hasn`t been rebuilt, It`s not that surpising there`s some foam coming out every now & then.

Well that's what I was thinking.  But if there is a screen inside and its had 37 years to accumulate junk in the airbox who knows?  This is an A/C shop that does other general work, but A/C is supposedly their specialty.  Sounds like I need to look at a diagram showing the hoses you mention and see if they're accessible from under the dash .... by a really big guy!  One or both of the front seats may have to come out.

Thanks, Jim

[MEK-Dangerfield]

This is out in left field, but here goes...

Is this your original dashpad? If someone replaced it, those AC ducts can be a pain to get back in the right place again.

[Road_Runner]

This is out in left field, but here goes...

Is this your original dashpad? If someone replaced it, those AC ducts can be a pain to get back in the right place again.

I believe its the original dash, shows plenty of wear & cracks like it is.  This was pretty much a one (woman) owner car and other than a crappy non-functioning radio and decent dual exhaust, I dont think anything was non-stock when I got it earlier this year.  That doesn't mean they haven't had the dash off in all that time.  I'm open to any & all suggestions because the 'clogged' theory just doesn't add up to me unless somethings built a next in there.

Thanks, Jim

[dutch]

I would think you can test them pretty easy.  On the backside of the heaterpanel are all hoses attached. I`m not sure if you would be able to test if a valve is stuck by sucking on them, but you will find out if there`s a leak in one of the hoses.

[Got JOB]

I don't believe there is anything that could come loose and clog the vent hoses. Could be a nest of some sorts in there but probably not. The blowers on these cars are not up to par with a newer car. I put a new blower motor on mine and run it on high and it still doesn't compare to my truck. Just my thoughts.

Ricky

[Road_Runner]

I don't believe there is anything that could come loose and clog the vent hoses. Could be a nest of some sorts in there but probably not. The blowers on these cars are not up to par with a newer car. I put a new blower motor on mine and run it on high and it still doesn't compare to my truck. Just my thoughts.

Ricky

I totally agree about the weaker blowers, I honestly was trying to remember how these things blew back when they were new.  But I can't help but think I should feel a noticeable difference on the high vs. med or low fan settings and for the most part I really can't.  My initial thought was it was a problem with either the switch or the blower, but it was the A/C shop that said it was a blockage.  I don't know, this thing has me scratching my head.  Did you have to remove the dash to replace the blower motor or is this something you can do from underneath the dash?

Thanks, Jim

[brads70]

I just installed new carpet. Turned on the blower fan for the first time ever and out came a whole pile of leaves!  

[Road_Runner]

I just installed new carpet. Turned on the blower fan for the first time ever and out came a whole pile of leaves!  
[/quote

That gives me hope!  I haven't seen any leaves so far, but if yours could get full of leaves maybe mine could too (crossing fingers).

Later, Jim

[quapman]

I totally agree about the weaker blowers, I honestly was trying to remember how these things blew back when they were new.  But I can't help but think I should feel a noticeable difference on the high vs. med or low fan settings and for the most part I really can't.  My initial thought was it was a problem with either the switch or the blower, but it was the A/C shop that said it was a blockage.  I don't know, this thing has me scratching my head.  Did you have to remove the dash to replace the blower motor or is this something you can do from underneath the dash?

Thanks, Jim

The blower motor on A/C cars is mounted from the engine compartment. 3 small nuts and it's out. Might be a good spot to check for leaves and/or nests also.

You might check the resistor array that's attached to the box, too. This is where the different speeds are switched. One or more resistors could be bad or shorted together. You'll probably need to remove the glove box & door for easier access.

[67vertman]

Have you thought about blowing some compressed air through the A/C duct lines at the blower motor?  Or check to see if you have a kinked/ colasped duct line? 

There should be much to obstruct flow through the duct lines. 

[Road_Runner]

The blower motor on A/C cars is mounted from the engine compartment. 3 small nuts and it's out. Might be a good spot to check for leaves and/or nests also.

You might check the resistor array that's attached to the box, too. This is where the different speeds are switched. One or more resistors could be bad or shorted together. You'll probably need to remove the glove box & door for easier access.

Thanks, that's good info.  I'll check these out.   Jim

[Road_Runner]

Have you thought about blowing some compressed air through the A/C duct lines at the blower motor?  Or check to see if you have a kinked/ colasped duct line? 

There should be much to obstruct flow through the duct lines. 

I don't have an air compressor at the present (want one big time) but I am going to try a shop vac tomorrow along with some of the other advice I've gotten here.  Anything I can rule in or out will help at this point.

Thanks, Jim

[purple1]

My ac box was half filled with crap. Looked like a mouse or two had made a nice home in the thing. Taking the blower motor off you still couldn't see it. You will never be able to blow all the crap out either if it is all filled up. Sorry you have it charged up already. I pulled mine and rebuilt it with a new heater core and pressure tested the ac core. How old is that heater core of yours? Might be something to think about.