No Heat
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From: Fredonia WI
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Does the blower motor work ... but just cold air coming out of the vents? Do the HVAC controls work to direct the air to the floor, vents, and defrost OK?
Thread Starter
Advanced
Joined: Oct 2014
Posts: 82
Likes: 0
From: Marietta Georgia
The blower motor comes on and adjusts based on the fan speed you select. The air coming out is just cool. I was working with the cooling and took the radiator cap off. There was some pressure built but not much. When I turned the engine on water started coming out of the filler cap like crazy. It seemed to be pulsing out. Got worse and went to spitting it out. I hope I am describing this correctly. Any idea why this is happening?
Race Director
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
Check the heater hoses where they go into the firewall. They should both be hot when the engine is warmed up.
Water expands a LOT when it warms up. You just might be seeing normal behavior. That water coming out of the radiator should be going into the overflow tank. That's what the tank is for. If you look at the side of it you will find COOL and HOT marks. As you can see, there is a lot of volume between those marks.
It's possible that you have a blown head gasket.
Check the heater hoses and let us know how that turns out. We'll go from there.
Do you have the C60 manual HVAC system with the sliders or the C68 digital HVAC system? The answer to that question makes a HUGE difference in how to proceed with troubleshooting your car.
Water expands a LOT when it warms up. You just might be seeing normal behavior. That water coming out of the radiator should be going into the overflow tank. That's what the tank is for. If you look at the side of it you will find COOL and HOT marks. As you can see, there is a lot of volume between those marks.
It's possible that you have a blown head gasket.
Check the heater hoses and let us know how that turns out. We'll go from there.
Do you have the C60 manual HVAC system with the sliders or the C68 digital HVAC system? The answer to that question makes a HUGE difference in how to proceed with troubleshooting your car.
Thread Starter
Advanced
Joined: Oct 2014
Posts: 82
Likes: 0
From: Marietta Georgia
Update info
I have the digital temp controls. Both radiator hoses are hot. The fans will not turn on - even when temp gets to 238. I do have the digital cluster out and have replaced the temp sensor between plugs 1 and 3 with a temporary temp. Gauge until I can save enough money for a new cluster.
Racer
Joined: Sep 2011
Posts: 400
Likes: 5
From: Bakersfield Ca
Check that vacuum line to heater water lever is working if it doesn't move use a wire to hold it open to see if water hot is going through the core. pic 1-2
the relay on drivers side fender controls the fan. pic 3-4 check wires make sure relay and wires are ok . I have a voltage problem and did stuff to get power you may screw up. Replace relay
check wires to sensor plug follow blue wire in picture to block
I have 87 I believe they are same
Steve
the relay on drivers side fender controls the fan. pic 3-4 check wires make sure relay and wires are ok . I have a voltage problem and did stuff to get power you may screw up. Replace relay
check wires to sensor plug follow blue wire in picture to block
I have 87 I believe they are same
Steve
Intermediate
Joined: Oct 2011
Posts: 42
Likes: 6
From: tavares florida
that green wire !
Check that vacuum line to heater water lever is working if it doesn't move use a wire to hold it open to see if water hot is going through the core. pic 1-2
the relay on drivers side fender controls the fan. pic 3-4 check wires make sure relay and wires are ok . I have a voltage problem and did stuff to get power you may screw up. Replace relay
check wires to sensor plug follow blue wire in picture to block
I have 87 I believe they are same
Steve
the relay on drivers side fender controls the fan. pic 3-4 check wires make sure relay and wires are ok . I have a voltage problem and did stuff to get power you may screw up. Replace relay
check wires to sensor plug follow blue wire in picture to block
I have 87 I believe they are same
Steve
Racer
Joined: Sep 2011
Posts: 400
Likes: 5
From: Bakersfield Ca
http://www.ecklerscorvette.com/corve...1984-1995.html
Click on cool for instructions. You may have a secondary fan like I do small can be seen through air dam on bottom of radiator
Steve
http://www.mamotorworks.com/Corvette...relay-622613-1
Last edited by AJ123; Nov 9, 2014 at 05:36 PM.
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Race Director
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
The auxiliary fan in front of the radiator is controlled by a thermal switch in the driver's side head (on 1986 and later cars -- was in the passenger side head on earlier cars) between spark plugs #1 and #3. It turns on a relay mounted on the front of the radiator shroud on the driver's side. You can determine if the relay and fan are OK by unplugging the green wire and connecting the wire to ground. The relay and fan should come on when you do this.
Race Director
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
You might have a problem with your temperature blend door. To find out, remove the blower control module from the evaporator housing. This guy:
Look in the opening and you can see the blend door. It will be rusty. Set the HVAC controls to 60°. The blend door should move to this position:
Set the HVAC controls to 90°. The blend door should move to this position:
If the blend door does not move at all or only moves in one direction then there is probably something wrong with your HVAC programmer. It is mounted inside the cabin on the firewall, above the accelerator pedal.
Do the above tests and we'll go from there after you report the results.
Look in the opening and you can see the blend door. It will be rusty. Set the HVAC controls to 60°. The blend door should move to this position:
Set the HVAC controls to 90°. The blend door should move to this position:
If the blend door does not move at all or only moves in one direction then there is probably something wrong with your HVAC programmer. It is mounted inside the cabin on the firewall, above the accelerator pedal.
Do the above tests and we'll go from there after you report the results.