C4 General Discussion General C4 Corvette Discussion not covered in Tech

Heater issues

Thread Tools
 
Search this Thread
 
Old Jan 7, 2016 | 05:07 PM
  #21  
hotrodbob01's Avatar
hotrodbob01
Instructor
Supporting Lifetime
 
Joined: Apr 2012
Posts: 152
Likes: 2
From: So.Cal. Central Coast Ca.
Default

How much different is the '89? I have the same issue for the A/C. I get heated air unless I get lucky and I hear the door moving.
Reply
Old Jan 8, 2016 | 01:20 AM
  #22  
Cliff Harris's Avatar
Cliff Harris
Race Director
15 Year Member
 
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
Default

Here is what the blend door motor looks like in '86 through '89 (you need to remove the ECM to see it -- borrowed from Agent 86's heater core replacement post):

Reply
Old Jan 8, 2016 | 01:32 AM
  #23  
hotrodbob01's Avatar
hotrodbob01
Instructor
Supporting Lifetime
 
Joined: Apr 2012
Posts: 152
Likes: 2
From: So.Cal. Central Coast Ca.
Default

Thanks.....
Reply
Old Jan 8, 2016 | 10:06 AM
  #24  
Brentwood Sooner's Avatar
Brentwood Sooner
Thread Starter
Advanced
 
Joined: Jun 2015
Posts: 98
Likes: 1
Default

Originally Posted by pcolt94
The door moves less than 90*, maybe about 70*. You don’t have to see it move. Set the temp control at 60 and see where it is. The set it at 90 and see where it is. It should change position.

One of the reasons the motors develop a problem is if the drain for the evaporator is clogged and back up, the water has nowhere to go and flows out into the cabin and right into the motor.

To get to the motor you need to remove the knee kick panel on the passenger side. Then underneath the motor hangs held on by 2, 7mm bolts and a connector.
How did you get the 2 bolts out that is near the radio panel?
Reply
Old Jan 8, 2016 | 10:43 AM
  #25  
Brentwood Sooner's Avatar
Brentwood Sooner
Thread Starter
Advanced
 
Joined: Jun 2015
Posts: 98
Likes: 1
Default

Originally Posted by pcolt94
The door moves less than 90*, maybe about 70*. You don’t have to see it move. Set the temp control at 60 and see where it is. The set it at 90 and see where it is. It should change position.

One of the reasons the motors develop a problem is if the drain for the evaporator is clogged and back up, the water has nowhere to go and flows out into the cabin and right into the motor.

To get to the motor you need to remove the knee kick panel on the passenger side. Then underneath the motor hangs held on by 2, 7mm bolts and a connector.
I got the knee kick panel out but where is the blend motor actuator at?

Reply
Old Jan 8, 2016 | 02:48 PM
  #26  
hcbph's Avatar
hcbph
Safety Car
10 Year Member
Liked
Loved
Community Favorite
 
Joined: Aug 2013
Posts: 4,431
Likes: 609
From: Minneapolis Mn
Default

I'm 'old school' and here's some old things to check. Get the car up to temp, have the heater turned on and up and feel both the heater hoses and see if they're both hot or not. If not, then coolant isn't flowing through the heater core.

One condition that can happen and cause this is the heater being air-locked. Happened in a couple of non-Vettes I owned at one time or another. Simplest solution I came up with was to find a parking ramp with the steepest inclines I could get. Go off hours when no traffic with the heater controls on full, engine hot, go up in low gear and keep the RPM's up. On one, once was enough, on the other had to do it a couple of times. Worked like a charm, be sure to fill the coolant reservoir so that when it cools down it sucks the coolant back into the radiator in place of the air.

If the other checks don't pan out, worth a try if the one hose stays cold and it's not a plugged core and not the controls.
Reply
Old Jan 9, 2016 | 12:43 AM
  #27  
Cliff Harris's Avatar
Cliff Harris
Race Director
15 Year Member
 
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
Default

Originally Posted by hcbph
with the heater controls on full, engine hot,
Coolant flows through the heater core 100% of the time, so the heater settings don't matter.
Reply
Old Jan 9, 2016 | 10:24 AM
  #28  
pcolt94's Avatar
pcolt94
Le Mans Master
20 Year Member
Conversation Starter
All Eyes On Me
Photogenic
 
Joined: Jan 2006
Posts: 5,621
Likes: 207
From: Orlando FL
Default

Originally Posted by Brentwood Sooner
I got the knee kick panel out but where is the blend motor actuator at?
Get on your back and get your head to the firewall with a good flashlight. Look up for the square like housing as illustrated in post 17. I use a 1/4" ratchet with a short extension and a 7mm socket. There are 2 screws holding it up, it only goes on way. Once the motor is off you can move the shaft for the blend door and make sure it is free. It needs to be back in the same position the get the motor back on.
Reply
Corvette Stories

The Best of Corvette for Corvette Enthusiasts

story-0

2027 Chevrolet Silverado 1500 First Look: Everything You NEED to Know!

 Michael S. Palmer
story-1

5 Best & 5 Worst Corvette Daily Drivers

 Joe Kucinski
story-2

The Headlights of Every Corvette Generation Explained

 Joe Kucinski
story-3

5 Best & 5 Most Overrated Corvette Track Packages of All Time!

 Joe Kucinski
story-4

Every 2027 Corvette Engine Explained

 Joe Kucinski
story-5

Designer Imagines A Corvette That Looks More Like a Corvette Than the Corvette

 Verdad Gallardo
story-6

10 Ugly Corvettes That We Still Kinda Love

 Joe Kucinski
story-7

Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer

 Brett Foote
story-8

10 Things Every Corvette Owner Needs (2026 Edition)

 Michael S. Palmer
story-9

8 Most "Only Corvette Owners Understand" Quirks and Problems

 Pouria Savadkouei
Old Jan 9, 2016 | 10:27 PM
  #29  
MRPVette's Avatar
MRPVette
Burning Brakes
15 Year Member
Photogenic
Liked
Loved
 
Joined: Jan 2011
Posts: 1,066
Likes: 89
From: Kingwood Texas
Default

Just did this job a few weeks ago. https://www.corvetteforum.com/forums...-corvette.html

Last edited by MRPVette; Jan 9, 2016 at 10:28 PM.
Reply




All times are GMT -4. The time now is 12:12 PM.

story-0
2027 Chevrolet Silverado 1500 First Look: Everything You NEED to Know!

Slideshow: Is the 2027 Chevrolet Silverado 1500 the best Silverado yet?

By Michael S. Palmer | 2026-06-16 08:01:12


VIEW MORE
story-1
5 Best & 5 Worst Corvette Daily Drivers

Slideshow: 5 best and 5 worst Corvette daily drivers

By Joe Kucinski | 2026-06-15 10:32:13


VIEW MORE
story-2
The Headlights of Every Corvette Generation Explained

Slideshow: The headlights of every Corvette generation explained

By Joe Kucinski | 2026-06-15 10:17:14


VIEW MORE
story-3
5 Best & 5 Most Overrated Corvette Track Packages of All Time!

Slideshow: The 5 best and 5 most overrated Corvette track packages ever.

By Joe Kucinski | 2026-06-09 12:46:45


VIEW MORE
story-4
Every 2027 Corvette Engine Explained

Slideshow: Every 2027 Corvette engine explained

By Joe Kucinski | 2026-06-09 12:16:31


VIEW MORE
story-5
Designer Imagines A Corvette That Looks More Like a Corvette Than the Corvette

Slideshow: A Jaguar designer's personal project imagines what a modern front-engined Corvette might look like if Chevrolet revisited the golden age of the Stingray.

By Verdad Gallardo | 2026-06-08 19:53:43


VIEW MORE
story-6
10 Ugly Corvettes That We Still Kinda Love

Slideshow: 10 ugly Corvettes that we still kinda love.

By Joe Kucinski | 2026-06-03 10:34:17


VIEW MORE
story-7
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer

A lot of money has changed hands at the online auction house over the years.

By Brett Foote | 2026-06-03 10:21:50


VIEW MORE
story-8
10 Things Every Corvette Owner Needs (2026 Edition)

Slideshow: 10 great gifts Corvette enthusiasts actually want for Father's Day!

By Michael S. Palmer | 2026-06-03 15:43:40


VIEW MORE
story-9
8 Most "Only Corvette Owners Understand" Quirks and Problems

Slideshow: These are the quirks, annoyances, and oddly lovable problems that every Corvette owner eventually learns to live with.

By Pouria Savadkouei | 2026-05-28 09:31:39


VIEW MORE