 Fresh Air Blower, Sound, but no fury |
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| rwilner |
 Oct 4 2010, 08:35 AM
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#1
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No Ghosts in the Machine  Group: Members Posts: 953 Joined: 30-March 10 From: Boston, MA Member No.: 11,530 Region Association: North East States  |
When I put both black levers to the right, I can hear the fresh air fan blowing but the airflow out the defrost and dash vents is quite minimal. The fan does work on all 3 speeds.
Similarly -- I just reattached all my heat, and even with the booster fan going in the engine compartment, there is just not much airflow. The engine compartment hose and the flapper --> firewall hose are new, the HX's are SSIs in good shape as is the rest of the engine compartment plumbing. What level of airflow should I expect? What should i check or refurbish to get better CFMs? |
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| McMark |
Oct 4 2010, 06:48 PM
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#2
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914 Freak! Group: Retired Admin Posts: 20,179 Joined: 13-March 03 From: Grand Rapids, MI Member No.: 419 Region Association: None |
Red lever has nothing to do with the fresh air blower.
I looked at the air flow system again to refresh myself. Here's the important points: 1. The dash vents are a 'branch' off the defrost vents. So anytime you're on 'defrost' you're also blowing out the side vents. This is something I had never considered. You'll get better windshield defrosting if you shut the side vents closed with the little lever. 2. The fresh air location lever (middle) and the hot air location lever (bottom, red) both work the same way. All the way to the left directs the air out the bottom. All the way to the right directs air out the defrost vent (see #1). 3. Pressing the floor lever down is supposed to shut off hot air completely. Moving the top dash lever all the way left is supposed to shut off fresh air completely. 4. If you're getting unequal flow between the left and right vents, you need to check the hoses and boxes for obstructions. You also need to confirm that your flapper boxes are opening fully at the exhaust system. And that your fresh air box valves are opening correctly (pull the paper tubes and look inside). |
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| rwilner |
Oct 5 2010, 06:15 AM
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#3
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No Ghosts in the Machine Group: Members Posts: 953 Joined: 30-March 10 From: Boston, MA Member No.: 11,530 Region Association: North East States |
QUOTE(McMark @ Oct 4 2010, 08:48 PM)  Red lever has nothing to do with the fresh air blower. yep, I get that. QUOTE I looked at the air flow system again to refresh myself. Here's the important points: 1. The dash vents are a 'branch' off the defrost vents. So anytime you're on 'defrost' you're also blowing out the side vents. This is something I had never considered. You'll get better windshield defrosting if you shut the side vents closed with the little lever. my car doesn't have a little lever, it has a wheel under the vent outlet, but it definitely operates as you describe. QUOTE 2. The fresh air location lever (middle) and the hot air location lever (bottom, red) both work the same way. All the way to the left directs the air out the bottom. All the way to the right directs air out the defrost vent (see #1). Yep -- on my car, this red lever does nothing to effect hot air flow direction. I checked and the cable is connected to the front-trunk flapper and seems to be moving the articulating arm. QUOTE 3. Pressing the floor lever down is supposed to shut off hot air completely. Moving the top dash lever all the way left is supposed to shut off fresh air completely. these both work as described in my car. QUOTE 4. If you're getting unequal flow between the left and right vents, you need to check the hoses and boxes for obstructions. You also need to confirm that your flapper boxes are opening fully at the exhaust system. And that your fresh air box valves are opening correctly (pull the paper tubes and look inside). At this point i'm suspecting the tubes because the flappers seem to be working. I will pull it apart over the long weekend and investigate. Mark -- is there any advantage to the OE tubing other than that it's OE? I'd prefer to use the more flexible, durable, and cheaper nylon tubing. |
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Posts in this topic
rwilner Fresh Air Blower Oct 4 2010, 08:35 AM
PanelBilly Take a close look at the paper tubes that the air ... Oct 4 2010, 08:46 AM
rwilner
Take a close look at the paper tubes that the air... Oct 4 2010, 08:50 AM Drums66
Take a close look at the paper tubes that the ai... Oct 4 2010, 12:16 PM rwilner I'm going to buy some of this tubing -- it has... Oct 4 2010, 12:38 PM rhodyguy where do you have the bottom lever positioned? Oct 4 2010, 08:50 AM rwilner
where do you have the bottom lever positioned?
T... Oct 4 2010, 08:54 AM Tom_T I agree Rich, if you've verified that your fan... Oct 4 2010, 11:03 AM rwilner
I agree Rich, if you've verified that your fa... Oct 4 2010, 11:43 AM burton73 I just rebuild the air box flapper box in a super ... Oct 4 2010, 11:59 AM McMark Our fresh air boxes like to collect leaves, acorns... Oct 4 2010, 12:37 PM rwilner
The levers work as follows:
Top Lever - Fresh air... Oct 4 2010, 01:42 PM McMark Get this 60mm paper tubing. It's OE style. Oct 4 2010, 12:41 PM jim_hoyland Be sure nothing has fallen into the windshield air... Oct 4 2010, 02:12 PM rwilner ok, an update:
Did some investigating and the pas... Oct 4 2010, 05:53 PM Racer Chris Rich, the McMaster link you provided is for a 5/16... Oct 5 2010, 09:52 AM rwilner
Rich, the McMaster link you provided is for a 5/1... Oct 5 2010, 10:54 AM rwilner
[quote name='Racer Chris' post='1379544' date='Oc... Oct 5 2010, 11:00 AM McMark The link I sent for paper tube is ~$5 / ft. ... Oct 5 2010, 12:08 PM |
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