A/C blower performance question
Thread Starter
Melting Slicks
Joined: Feb 2008
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A/C blower performance question
I have a 1975 Corvette convertible. Over last winter and Spring I had the AC system rebuild and the car painted. I have taken short drives around town but today was my first opportunity to go on a real road trip. It was 90 degrees out and I was content with the top down however the wife was not. So I put the top up and have the air on max. The high speed blower had not been working and I replaced the resistor under the hood and that took care of the problem. Now as we are driving with the top up and the air on max and the blower on maximum it was still inadequate. There was enough Force to blow the air out to about the steering wheel yet not enough to really make it reach the passengers. I would expect in a small cockpit like that that blower should have blown hard enough on max that the occupants should have been able to felt it quite well. Is this the way they were or is there something else I should be looking at?
Melting Slicks
Joined: Sep 2006
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From: Wichita Kansas
From what I have read and experienced, the blowers in the C3 aren't that whippie, but you could try putting a larger ground wire on the motor and see if that helps. There could be a lot of leaves and debris in the box (but if you redid the system you probably already cleaned that up?) A lot of owners have replaced their blower motors with ones for the C4's, as they seem to provide more forced air. You will have to fashion a shim/spacer to go between the box and the replacement blower motor, as the cage fan on them is longer than that of the C3. Good luck
Burning Brakes
Joined: Sep 2005
Posts: 1,050
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From: Lewes Delaware
Dirt or paint overspray on any electrical connection will introduce resistance in the circuit thus reducing motor speed. Clean all electrical connections between the switch and the motor. I remove them and use spray electrical cleaner (I use WD-40 Specialist Electrical Contact Cleaner Spray, available at Amazon) on the contacts. Follow the directions on the can. Also spray it in the switch to clean those contacts. I have used this stuff (it is a non-polar cleaning solvent) on my corvette and to clean track on my HO scale model railroad. It does not leave a film and inhibits corrosion buildup from exposure of the contacts to the atmosphere.
Like Kansas123 said, the blowers are not that powerful, but the above is worth a try before replacing it with a C4 motor.
Fran
Like Kansas123 said, the blowers are not that powerful, but the above is worth a try before replacing it with a C4 motor.
Fran
Le Mans Master
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From: mount holly NC
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Is this what your asking?
Le Mans Master
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From: mount holly NC
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C4 fan motor question
Will an 84-85 C4 fan motor bolt right up to the existing C3 firewall mounting holes without modification? I know the fan requires a spacer.
The connections look the same.
Thanks,
Marshal
The connections look the same.
Thanks,
Marshal
Team Owner
Joined: Jan 2006
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From: Crossville TN
Aftermarket replacement blower motors are NOTHING like the way the original motors were made. Just do not buy the cheapest blower motor available! And leaves and debris DO collect in the HVAC plenum area over many years of use. If you did not specifically ask for that area to be cleaned out, the A/C rebuilder would probably not have done so. When you remove the blower motor, use a ShopVac and a flex hose to suck out any loose stuff in the 'bowels' of that plenum.