Header users beware!
Thread Starter
Burning Brakes
Joined: Jan 2007
Posts: 921
Likes: 0
From: Houston TX
Header users beware!
The heater box control failed on my 85. I presumed it was do to a mouse raising havoc behind the dash. After looking everywhere for the problem, I decided to wave the white flag, bend over and bring it in to the stealership.
After nearly 5 hours, the mechanic was ready to give up when he found a tee junction that wasn't shown in the schematic. That directed him under the right side rear header pipe where a harness with the vacume hose and what appeared to be fuseable link had burned through.
He repaired the hose ($680 all labor).
That area still looks dicey. I would like to somehow reroute that harness away from the headers beacuse fuseable link + oil + headers = fire.
After nearly 5 hours, the mechanic was ready to give up when he found a tee junction that wasn't shown in the schematic. That directed him under the right side rear header pipe where a harness with the vacume hose and what appeared to be fuseable link had burned through.
He repaired the hose ($680 all labor).
That area still looks dicey. I would like to somehow reroute that harness away from the headers beacuse fuseable link + oil + headers = fire.
Thread Starter
Burning Brakes
Joined: Jan 2007
Posts: 921
Likes: 0
From: Houston TX
No, and there's very little room to get a camera or hands or anything in there. If you look between the 2 rear pipes on the right side, you'll see the cooling fan temp switch (this is on an 85 now) and the harness runs just below it so it's between the headers and the motor. A horrible place for stuff like that don't you think?
Thread Starter
Burning Brakes
Joined: Jan 2007
Posts: 921
Likes: 0
From: Houston TX
I looked under the car at the stealership and saw first hand what the mechanic was talking about before he made the repair.There are 3 reasons you don't know this: 1. You don't know everything. 2. It's not in the GM schematic. 3. It may be due to some modification from who knows when for who knows why.
Race Director
Joined: Aug 2000
Posts: 14,130
Likes: 7
Cruise-In II Veteran
I wonder if thats the plastic vacuum hose for the hvac system.It runs through with the wireharness into the car through the firewall junction,near where you said it was.When that hose breaks,melts,the vents for the heat or air dont work properly.
I fixed these on other GM cars before.I do not know if someone rerouted your lines or wires too close to the exhaust system.But the tube usually runs in back top of the engine into the wireharness loom,then through the firewall.
I fixed these on other GM cars before.I do not know if someone rerouted your lines or wires too close to the exhaust system.But the tube usually runs in back top of the engine into the wireharness loom,then through the firewall.
Team Owner
Joined: Feb 2006
Posts: 24,460
Likes: 7
From: sw Ohio
I am no fool. I looked under the car at the stealership and saw first hand what the mechanic was talking about before he made the repair.
There are 3 reasons you don't know this: 1. You don't know everything. 2. It's not in the GM schematic. 3. It may be due to some modification from who knows when for who knows why.
I looked under the car at the stealership and saw first hand what the mechanic was talking about before he made the repair.There are 3 reasons you don't know this: 1. You don't know everything. 2. It's not in the GM schematic. 3. It may be due to some modification from who knows when for who knows why.
Team Owner
Joined: Jan 2003
Posts: 20,254
Likes: 221
From: Summerland B.C. Canada
I am no fool. I looked under the car at the stealership and saw first hand what the mechanic was talking about before he made the repair.
There are 3 reasons you don't know this: 1. You don't know everything. 2. It's not in the GM schematic. 3. It may be due to some modification from who knows when for who knows why.
I looked under the car at the stealership and saw first hand what the mechanic was talking about before he made the repair.There are 3 reasons you don't know this: 1. You don't know everything. 2. It's not in the GM schematic. 3. It may be due to some modification from who knows when for who knows why.
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Team Owner
Joined: May 2002
Posts: 24,337
Likes: 25
From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
All of those dampers are vacuum actuated. That sounds like possibly the main vacuum source to the whole heater box. If moving the levers in the car causes big sucking noises, that hose should be one of the first things he looks at. But I'm guessing he tore the whole dash apart first. This is akin to removing your volt guage to find out why the battery voltage is low.
My hindsight is 20/20.
Thread Starter
Burning Brakes
Joined: Jan 2007
Posts: 921
Likes: 0
From: Houston TX
Do you need more universal health care? Why is this so baffleing to you? I described exactly where the harness is. It's probably the same on your 86. If your not aware of it's presence, your beautiful yellow car may turn black someday. It might be worth sticking your nose in there and having a look don't ya think?
Team Owner
Joined: Jan 2003
Posts: 20,254
Likes: 221
From: Summerland B.C. Canada
Do you need more universal health care? Why is this so baffleing to you? I described exactly where the harness is. It's probably the same on your 86. If your not aware of it's presence, your beautiful yellow car may turn black someday. It might be worth sticking your nose in there and having a look don't ya think?
Race Director
Joined: Feb 1999
Posts: 12,772
Likes: 17
From: Indianapolis IN
I dont have any wires to my HVAC running close to my headers, I might have re-routed them over the top of the box when I put the headers on.
$600 is crazy, but thats what the stealerships charge, I'm sure that you knew you were gonna get tagged, but obviously you need to reroute your harness asap.
$600 is crazy, but thats what the stealerships charge, I'm sure that you knew you were gonna get tagged, but obviously you need to reroute your harness asap.
Melting Slicks
Joined: Oct 2000
Posts: 3,426
Likes: 4
From: Heidelberg PA
Cruise-In V Veteran
I am sure I know what you are talking about. the vacuum line does go into the harness behind engine & pops back out and goes to an area near the bottom of the blower box.
I have all wires that come withen 6" of the headers covered with heat tape to protect them.
Interesting post - headers = heat, heat = damage if not managed.
I have all wires that come withen 6" of the headers covered with heat tape to protect them.
Interesting post - headers = heat, heat = damage if not managed.
Melting Slicks
Joined: Feb 2005
Posts: 3,204
Likes: 4
From: Midland Georgia
St. Jude Donor '06
Coated headers?
Are your headers coated or wrapped with header wrap? If not do it... I used to post very often on the damage uncoated headers were inflicting on my 94. Bottom line was I coated the headers and it solved everything. Of course, I had to make sure nothing was within a few inches of the headers as an abundance of caution... Take them off and ship them to Jet-Hot or similar coater... Problem solved!
Race Director
Joined: Sep 2000
Posts: 17,298
Likes: 33
From: The Top of Utah
Originally Posted by AGENT 86
I'm not trying to be a dick, it just sounds like the dealer screwed you. The vacuum line that feeds my HVAC goes into the wire harness behind distributor and then through the firewall near the middle.
There is another plastic vacuum line that passes through the firewall to the right of the engine that operates the heater water control valve.
RACE ON!!!
Le Mans Master
Joined: Aug 2004
Posts: 5,141
Likes: 7
From: Metairie Louisiana
Are your headers coated or wrapped with header wrap? If not do it... I used to post very often on the damage uncoated headers were inflicting on my 94. Bottom line was I coated the headers and it solved everything. Of course, I had to make sure nothing was within a few inches of the headers as an abundance of caution... Take them off and ship them to Jet-Hot or similar coater... Problem solved!
Thanks
Melting Slicks
Joined: Feb 2005
Posts: 3,204
Likes: 4
From: Midland Georgia
St. Jude Donor '06
How much of a difference does the coating make in temp before and after? My headers are coated and still get very hot. Enough to burn through one of my wire boots that was touching. They do cool down way faster, quick enough to touch after about 10 minutes. What type of problems were you having? Was it just the heat that was radiating out? I guess since mine have always been coated maybe I don't realize how much worse it could be non-coated. I am still very happy with my headers.
Thanks
Thanks
Even coated I am careful to keep things away from the headers. The rule here is ZERO contact with the headers! I took alot of time to make sure things are routed
Instructor
Joined: Aug 2006
Posts: 220
Likes: 12
From: Hagerstown MD
i am curious about this myself..after my headers were installed the mechanic told me that there is a harness on the passenger side that is a couple of inches away from the header and he recommended that i header tape the harness.....i still do not see what he was refurring to but this post has me wondering now....i better look better
Thanks BEEP
Thanks BEEP