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Interior coolant leak.

Paveltolz

Paveltolz

Доверяй, но проверяй
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Location
Saratoga Springs, UT
I've been noticing the smell of coolant inside the truck the last couple of days. Took a moment to investigate and discovered the carpet on the passenger side of the hump was wet, about a 3" diam spot, as were a couple of spots on the floor mat. Feeling around the heating components and such, things were damp as well.

No external leaks from the feed and return points in the engine compartment.

I twisted up my ankle today and the meds were kicking in so I didn't take much more time than that to investigate. :eek:

I've searched "Leaking" and "Heater" but so far have only discovered one reference to the rear heater on a 95 Sub.:nonod:

Any suggestions where I should focus tomorrow between med dosings would be appreciated. Its going to be warmer this weekend so I'd like to be able ascertain what's going one and effect a repair rapidly as I've promised snookums I'd replace the CV axels on her VW this weekend. :skep:

Thanks in advance.
 
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X2.....Heater core......they're a bit of a PIA to change........Dashboard removal or I've heard of people, dropping the column and dropping the dash back to get access to it.
 
Never done that job, but pretty sure you can access the heater core from under the dash. I've heard from my friend/mechanic its not to bad of a job.
Never seen a write up here on it. You should do one.
 
I have had some success over the years by unhooking the heater core lines & adding a small amount of stop leak directly into the core...might get ya by for longer then you think depending on what has failed. Just use the stop leak sparingly directly into the core, then hook the hoses back up & take it for a good long drive. Not my proudest moment in repair history, but it might just repair a small seem or coil leak for a good long while.
 
Thanks, I'll get a good look at it tonight/tomorrow between Lortab doses and see what it will take. Core can be had new for about $62 plus S&H. I'll see about the write up. I'll get pictures and once I've got it done I'll know how it should have gone and post it up accordingly. As for the stop leak, that sounds like a plan too. I'll be sure to not put it in the engine like that poor guy over at The Place did. I've had enough of "being an example to others of what not to do" for a while.

Paul
 
I think BigT tackeled this job and did a writeup, or at least someone on here did in the last year or so. Someone definatly wrote about taking their dash apart and putting it back to together.
 
Must not have addressed the heater core as it didn't pop on the searching. I tried dashboard to see what lists and apparently my 'key word' selections skills are weak.

I'll just go through the manual tonight and pull the sections dealing with the heater core and it should reference the dash dissassembly. I saw it last night and I know there was mention of the glove box and ECM coming out so it sounds like I'm in for an advanced rubic's cube session.

Going back to the fear of serving as an example to others, how much coolant do I need to drain before I find out by dumping the whole system in the cab?
 
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That is correct, I had to change the evaporator, but the heater core is accessed the same way: drop the dash. It's basically 3 steps: 1) remove driver seat: 2) drop steering column; 3) drop dash. Then you'll have access to the heater box. Lot of little stuff in between those. It can be done in a weekend. The second time it can be done in hours. There is a post here on dash removal how to.
 
ON EDIT: Ok, Saw BIG T's post. Thanks amigo, appreciate it.

I've been reading through the GM Service manual I have and it doesn't help that my truck is a 96 and the manual is for the 97 so the dashes are just different enough that I wonder what surprises I'll find. “Roll instrument panel back” sounded ominous enough and why it would make reference to the steering column assembly I have no idea though but I guess I'm going to find out. Great (sarcasm on). Wish I had the funds to fly BIG T up here to point me in the right direction. Oh well.

Other than that, it looks fairly straight forward. I do plan to pull the fender well to get at the heater inlet and discharge hoses and the exterior bolts that hold the whole heater/air exchange assy. Also I plan on an interior tear down similar to what 88GMCK2500 did with his new 6.5. With the anti freeze in the carpet and the youngest accidently discharging a blast on the fire extinguisher in the cab, the cab and carpet need a good detailing. Then there is the coolant leak and CV joints on the VW.

I’m just glad the ankle is feeling better.
 
The dash can rotate backwards. I have never done a heater core in one of these but I did remove the entire dash from one at a junkyard. It sucked. Have a cordless drill with bits handy. Lots of screws IIRC. IIRC The top pulls backwards.
 
I could be wrong, but Im pretty sure you can do the heater core without tilting the dash and going through all those pains. On my 93 I was able to get in there to clean the evap core and it sure seems like I could have popped the heater core out.
I seem to remember certain points (about 4) are melted together on the housing, drill those out then on reassy used bolts, washers and nuts to put it back together.
 
If a burb is the same as a CK then it is a fairly easy job.

Drob the bottom cover.3 hex bolts front,3 or 4 bolt at the firewall .May have to remove carpet.
the bolt over the tranny is high up behind it against the firewall(feel only),one is right between where the core tubes go trough the firewall
Core is right in sight after you get the cover off.
1 bolt holds the core in place.
The bitch is to get the hoses off the tubes in the engine bay.
Can remember how i got that done.I think i took the turbo out, not sure though,its been a couple years.
Inner fender removal might help.I 'm sure i did not do that.

Have fun
 
Paveltolz, give me a call saturday if you need/want a hand. I haven't heard back from the guy that has the motor up north, so that might be a bust this weekend. Happy to lend a hand if you need/want it.
 
OrionThade said:
Paveltolz, give me a call saturday if you need/want a hand. I haven't heard back from the guy that has the motor up north, so that might be a bust this weekend. Happy to lend a hand if you need/want it.
Click to expand...

Thanks for the offer, remember the old addage about "do not volunteer for anything" though. I just may take you up on it. Side note, Leroy called and said the lights were an 'easy do' so they should be back next week which is when I may end up doing this job since it is a long weekend and I'm anticipating a slow and steady "while I'm in here" progression of tasks to complete.

Ace, Leroy, Bison et al, Thanks, I hope it is this easy. Having had the Turbo out recently, I think removing the fenderwell or at least the down pipe would be the ticket to getting at the heater hoses and any bolts in that area the manual refered too. All the dash moving may be a 96 vs 97 difference since they changed the passenger side dashboard (and added air bags later). I just know the pictures are different from what I've got.

Big T, could you post up the link to your dashboard removal thread? I'm only finding "dash board" and "evaporator" on your AC High Side and the 'wrapping up 2010' threads and was that work on the 95 you gave your son or the 99?
 
Yep, got the lights will finish them up today if time permits.
bison is correct, now that he discribed it I can remember. My discription above about the melted points at the joint would be for cleaning and or removing the evap core.
The hoses on the heater core are easy also, just unclamp them reach down there and pull them off. I have a special tool for breaking the bond hoses sometimes get. It looks like a screwdriver handle with a thick ice pick except the end is bend 90*.
Have another with 180* bend. Make it easy to pull hoses off. I like to use oring lube on the hoses when going back together. It helps alittle in preventing hoses from welding themselves to the core. Use it on radiator hoses too.
Their was a product called Aqualube that I liked for that. Can't find it anymore?
 
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