Cabin Air help

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Dec 13, 2013 | 10:21 PM

psycho dad

Thread Starter

Racer

Joined: Nov 2009

Posts: 489

Likes: 1

From: Suffolk Virginia

Cabin Air help

My 76 has no air coming into the drivers compartment. All the ductwork is intact and I can hear the fan motor running. I was told there is probably a blockage, probably a rat's nest somewhere around the heater core.
If I get properly motivated and its not to cold this weekend I may go in to have a look. Before I start ripping out the console, is there anything else, possibly less invasive that I should check first?
thanks!
- Jay

Dec 13, 2013 | 10:40 PM

Hammerhead Fred

Melting Slicks

Joined: Mar 2005

Posts: 2,095

Likes: 298

From: Midlothian VA

Quote:

Originally Posted by psycho dad

If it's an A/C car the blockage will likely be on the up stream side of the evaporator coil as it is between the heater core and the blower. Check the intake area above the fan motor passenger side of the windshield. Over the years "stuff" builds up on the intake side of the evaporator eventually blocking all air. You likely can't see down in there easily but may be able to determine if there's a blockage. Mine had a bird's nest in there which had been blown up against the evap coil. Had to remove the evap case to clean it out. Time consuming but not the worst fix on the car.

Dec 13, 2013 | 10:47 PM

psycho dad

Thread Starter

Racer

Joined: Nov 2009

Posts: 489

Likes: 1

From: Suffolk Virginia

we're practically neighbors, come help me!

I pulled back the screen and looked down toward the fan motor, nothing there. Sounds like you went in through the engine compartment and not through the dash?

Dec 14, 2013 | 12:09 AM

Hammerhead Fred

Melting Slicks

Joined: Mar 2005

Posts: 2,095

Likes: 298

From: Midlothian VA

Quote:

Originally Posted by psycho dad

we're practically neighbors, come help me!

I pulled back the screen and looked down toward the fan motor, nothing there. Sounds like you went in through the engine compartment and not through the dash?

Way too cold to visit my neighbors near the beach

Yes, you go through the engine compartment should the evaporator coil be blinded with trash. To get to it you must remove the evaporate box from the engine side. Looks daunting but really not all that bad.

There's practically no way for something to get between the evaporator and the heater core. I suppose something could be blocking the air flow from the interior side of the heater but I've never seen it. If you pull your passenger dash and distribution box and get to the heater core finding nothing you'll know it's on the other side of the evaporator vs. the heater core. Once you get to the heater core fire up the blower - if nothing is coming through you'll need to move to the engine compartment.

Try pulling the blower motor and reaching down inside to see if you can locate something in front of the evaporator. Bring your double jointed elbow though. I taped a section of water hose onto the end of my vacuum cleaner and fished it into the cavity.
Pulled out lots of stuff but eventually not enough to fully restore the air flow. I think a bit larger & clear hose would have been an improvement - could get at the larger bits and see the stuff going through the hose.

Dec 14, 2013 | 08:16 AM

commander_47

Burning Brakes

Joined: Oct 2011

Posts: 956

Likes: 86

From: McDonough Georgia

On my 81, you can get in there through the upper right vent under the hood.

You may also be able to pull the kick panel on the passenger side.

Carefully snake a vacuum hose past the vent into the air box under the hood.

I pulled leaves an pinecones out of mine.

Dec 14, 2013 | 09:24 AM

psycho dad

Thread Starter

Racer

Joined: Nov 2009

Posts: 489

Likes: 1

From: Suffolk Virginia

I like the vacuum idea, no disassembling.
Thanks for the help guys!

Dec 14, 2013 | 09:53 AM

Easy Mike

Team Owner

Joined: Jun 2000

Posts: 38,923

Likes: 1,482

From: Southbound

Cruise-In II Veteran

Quote:

Originally Posted by psycho dad

...Before I start ripping out the console, is there anything else, possibly less invasive that I should check first?...

Why not stay inside where you are warm and comfortable, and check the HVAC diagnostics page in the AIM? That will give you a clue where to begin your problem solving.