'75 911 cabin air flow

[jkshadow2]

I have a '75 911S coupe with the air conditioning removed (how I purchased it). I live in CA and it can get pretty warm while I'm driving, so I like to direct some air in the cabin.

When I select the climate control valve to direct air towards the floor, I get pretty good flow. If I set the lever to have the air come out of the two tiny side vents and the defrosters it is pretty anemic. It this normal for a Porsche? I can hear the blower motor working, but it does not produce much felt air flow. Is my blower motor kaput?

Any ideas would help.

Thanks

[mcchesneyc]

Check all the hoses in the front of the car. I had a similar problem just after I got the car from my son. Mine still has all the AC installed (doesn't work though - another project at some point). Checking all the vent connections in the front, I found that a couple of the large vent hoses were disconnected or rotted. Once replaced and reconnected I get great airflow (while moving) through the defroster vents and dash vents.

[Pedro '84 Coupe]

Once you get the side vents and defrost sorted, you should install a Kool'n Duct: Kool'n Duct - 911 Under dash duct for better air flow

No affiliation, just another happy customer. Good luck!

[75 911s]

Crack the pop out windows. Makes all the difference. Top lever on fresh air blower all the way to the right. Second lever to the "Up" arrow"

[bkreigsr]

here's a simple - easy-to-understand - explaination (with schematic) -

any questions?
Bill K

[pmax]

Originally Posted by bkreigsr

any questions?
Bill K

As a matter of fact, yes, if you can translate that Stuttgart-speak or a poor attempt at translation from German for us, I have one. WTH do they mean by maximum ventilation when the fresh airflow is shut off ? Everytime I read that page, it's a head scratcher.

[fanaudical]

Bill - Those instructions don't quite apply to a '75. No center vents. The fan and outside air controls are combined on the same lever.

I agree - check hoses to make sure they're not disconnected.

Something I did when I removed my AC was to leave the below-the-dash vents. I gutted the evaporator box, left the fan, and ran a duct from the front condenser fan inlet to the evap box. Lots of air flow in the summer...

[spyerx]

open windows
open rear pop outs
adjust cool air to feet

DRIVE FASTER

[dannobee]

If it gets hot, just pull the clock out, you'll get WAY more airflow.

[MichaelSJackson]

Here is a thread where they use a dash vent from a 2004 Ford F150 to replace the clock. Has directional vanes, rotates 360 and can be "closed".

Ford part number is # 4L3H-19893-AJW