Passenger side air leak

[goose4433]

I've searched the forums with no luck. Been doing a lot of cold weather driving in the 60 lately and have noticed a pretty good draft coming out near the passenger's feet. As far as I can tell it appears to be coming out near (or from) the blower fan, specifically I think from the foam filter around the blower but I'm not 100%. The draft is also clearly speed dependent which has me looking for holes in the firewall but I can't find anything. Also, turning the air to re-circulate makes it worse which is a bit odd to me. Makes it hard to trouble shoot since I need to be driving to feel the draft.

My best guess right now is a loose hose or something and I was planning on pulling the blower motor to inspect but thought I would ask for any insight first. Anyone have any guess?

 

[morganism]

Distributor breather hose thru firewall ? You can drop blower motor and vacuum in there, may help if the selector doors arn't closing

 

[goose4433]

Should have mentioned I have a 350 under the hood as well. You're saying just pull the blower and take a look?

 

[FJ40Jim]

There is a door (actually a pair of saloon doors) that open/close for outside air or recirc(inside) air. This recirc door has to be 100% open or closed to seal up. If it is anywhere in between, then the ram air will go around the doors and come out on the passengers feet through the grill that should be where recircd air is picked up.

 

[OSS]

The slider push/pull cable that manually push/pulls air flow doors (recirculate & fresh) can get sticky in its plastic surrounding housing (or whatever it's called). Also these cables can rust where they are exposed to the air. Maybe try lubricating the cable (it's actually a solid steel wire) where it enters its black housing with a penetrating oil. My cable became so sticky it eventually wouldn't budge and the wire would bend instead of slide inside its housing.
After I lubricated it on both ends where it enters its housing and actuated the cable in & out a zillion times to lube it up - the cable eventually slid like ice on glass. Super smooth. Air blend doors now snap shut like a new car.

 

[goose4433]

Looks like @FJ40Jim was right. There are two saloon doors and it looks like the one in the rear is not shutting properly. So, that means the ram air from outside is constantly being pulled into the system. The cable moves just fine.

You can't see the rear door in that picture but it's there. When recirc is selected it opens the door to the passenger compartment (of course).

In my case it looks like the lever to the rear door has disconnected and it won't shut. You can kind of see the top metal arm in the pic below is not connected.

You can see it pretty clearly here.

That little brass colored tab in the back is where that arm is supposed to attach. There was a piece of white plastic there when I first started digging around but that fell off into some crevice. Does anyone know if it's possible to reattach this somehow? I doubt there is a part number or anything, but maybe? Also, do you think I'm going to need to pull the whole assembly to get that thing repaired? My hands seem a bit too large to fiddle back there.

 

[morganism]

Are all your dash light bulbs burned out? Is your air intake just below grill filled with leaves? Might be time for a dash off LED upgrade.

I think it is really hard to pull that whole system out if you still have AC, but since you have gone 350, might not be a big deal.

Pics for replacing heater core?

how to remove heater core plastic shroud?