I need some help from the experts.

I ordered a new heater core, just to be safe, and decided to replace it while replacing the hoses. Unfortunately, the AC Delco shop gave me the wrong core. I also noticed that the upper and lower radiator hoses they gave me won't work. Not very happy as I cut the lower hose to remove it. The upper hose still looks perfect on the inside, so I'll just reuse it.

I did everything I could To remove the two heater core hoses (62&63), but I'm stuck on the exit hose(63). This is the one that is shaped like a question mark, so it comes out 3 inches, 90* straight down and then 45* back toward the firewall. The lower part of the hose connects to a rail (66) that is bolted to the body (68) and comes back toward the front of the engine along the inner wheel well. This "?" shaped hose connected to the right side core hookup with a hose clamp and connects to the rail on the bottom with a hose clamp. The problem is that you can't access the bottom clamp to remove the hose. How have you guys done this? I couldn't remove the hose without cutting it off the core so now it has to be replaced. I have about 5 hours into this and the original core is still in the car! See diagram.

Just an FYI, I also replaced the thermostat so I had to remove the throttle body and TPI air intake. No big deal there though, just time.

 

I was able to access my bottom clamp fine. Its rotated to a position you cant turn it? What style clamp is it? Most have a hex head as well.

 

The clamp is down about 6 inches under the core connection. There is no way to get a hand in there or a tool to loosen the clamp. It's facing the center of the car below the valve cover. The coil has already been removed, but that isn't helping access the lower clamp.

 

Scott,number 66 is held to the body with 2 10mm screws.
If there is no way of getting at the hose clamp,maybe just remove these 2 screws so youcan gain access to the clamp.
Don't know if that helps or not,just my 2 cents.

 

i had the same problem as you with that clamp in my gta. i just ended up taking the distrib cap off and i was able to get to it. not easily but i was able to do it with just the cap off

 

I did remove the 2 bolts holding the rail on. I also disconnected all the hoses to the rail. Now I'm trying to get the rail out so I can access the clamp. I am gaining a new respect for the automotive repair person that does this stuff regularly.

 

Scott, just wondering, are you replacing the heater core on your IROC? Was it or a hose leaking? At 14K miles?

 

I'm replacing it on my IROC. I know of people that had them go at 20k miles. The core is 21 years old and so are the hoses. I'm trying to replace all rubber so I don't get stranded whn I am driving it. My dad's 82 Pace Car recently dumped the core all over the passenger carpet. This promptd me to replace mine before it or a hose goes.

I also just looked closer, the screw on the clamp on that hose I can't get at it facing the firewall. I can't get the rail out and I can't access the clamp screw!!!

 

On a good note, my radiator looks as good as new!

 

That pic of the hose helped. So you've already cut-off the hose at the top where it connected to the core, and now you're trying to access the bottom clamp, right?

The clamp's screw has a hex head, so you oughta be able to turn it with an open-ended or boxed-end wrench, if you have one of that small size that's long enough to reach it.

Also, have you tried rotating the whole piece of hose, turning it around? It probably won't move at first. But if you can grip it hard enough and twist it back-and-forth, you oughta be able to break it loose and turn it around so the head of the clamp is facing out.

 

Finally.....

I couldn't find my 1/4 inch box-end wrench so I borrowed one from the neighbor. I was able to loosen it enough to drop the clamp. I then cut the rest of the hose off. One thing that really helped in loosening the clamp was to remove the core (duh). Once I did that, I had enough room to swing the wrench 1/2 turns. I put the new hose on and positioned the clamp with the screw head facing the drivers side. After removing the distributor cap, I was able to tighten the screw with the 1/4" universal I got. I started putting everything back together. All I need now is the new heater core and the lower radiator hose. Almost done!

I also removed the overflow tank and cleaned it out. Bleach works wonders. I might still replace it as it has some yellowing, but it looks alot better than it did.

 

HAHA! I did the same thing as far as that clamp!I don't know why in the heck gm placed it that way.
On the overflow tank,I would say replace it.They are pretty cheap,and to be honest with you,your car deserves the best.

 

Yes, bleach works well. Mine looked great after I finished cleaning and bleaching it, too. But I decided to get a new one anyway. And after it came, wow, what a difference! The one I thought looked so great, didn't look so great afterall. So I'd also say replace it... especially since new ones are still available.

 

ya heater core replacement sucks i just got my car back to geather and running a few days ago after it sitting for three months cause i couldnt find the right core i hope ill never have to replace it again

 

The Worst part to me is you almost have to remove the dash completely, and apparently the Engine, ok its not that bad...

I have not done one yet, but some day I probably should just to be safe. What kills me is the way they put the screws on the inside of the car in places where you really cant get to them from underneath the dash.

JOhn

 

ya its like they built the car around the heater box

 

If you do it right you can remove and replace them in about 4-5 hrs like I do.
Im just cool like that tho

 

i had to do mine a few months after buying my car. it sucked BADDDDDDD

 

If it weren't for that one hose, the replacement was a piece of cake. On the 87 model Camaro, I had no hush panel so I was able to access the cover easily. There are 3 screws on the bottom and one on the right side under up under the dash. I removed the dash cover and went thru the speaker opening with one hand and up the side and over the top with the other. I held the ratchet with my left hand while I ratcheted with the right. The cover came right off. I then removed the 4 screws that hold the heater core into the housing, disconnected the hoses and gently pulled it out.

The thing that's taking me so long is that I'm replacing upper and lower radiator hoses, heater core hoses, the core itself and the thermostat. I'm also trying to do it without making a mess of my detailed engine!

One thing I have found issues with is AC Delco advertises the upper and lower radiator hoses for an 87 are the same as an 88+. The placement of my AC compressor is in direct line with the hose that AC Delco says is correct. The lower hose is also not big enough and isn't molded to the correct shape. The upper hose on my car leaves the radiator, turns 90* to the left for about 10", then does another 90* to the thermostat. The replacement comes out, goes 90*, starts a 45* for 8-10", does another 45* into the thermostat. That no workie.

Here is the shape of mine now:


and here is the hose they suggest:


What I need:

 

Dang Scott,its been so long since I saw your car in person that I forgot how pretty that eng. comp. is!
I know you HAD to be very cautious in doing this work to keep from scratching any of the original paint under there.
So,I now consider you a pro at this!
Ya wanna do a heater core replacement in my 81?
LOL! just kidding man,and glad you got that nasty clamp out of the way.

 

Heater core replacement sucked big time for me. About a year ago I had to go through the whole dash removal process twice, thanks to faulty parts. The second time around was only a week after I'd replaced the first one. At the time, I was in South Dakota in January...working outside....needless to say, I was in a hurry. I got so pissed I just cut the lines, went to the hardware store, bought a T connector, and just rerouted the whole damn thing.

 

My interior is out too- BOY! I just can't wait to tackle this now!!- lol At least I have this thread to look back on though.

 

ok fellows that have done this I need some help getting to the heater core itself.. I have an 83 trans am up here in Alaska.. started smelling anti freeze and then found some on the passanger side floor mat..
I pulled off the top of the dash (might as well put some new speakers in too!) And alot of the other dash pieces Found the 3 screws mentioned in previous emails but still can't get the panel off.. Could there be another screw?? It looks like I might have to take the center console out? If anyone can send a step by step procedure it would be greatly appreciated
thanks
Flash

 

there is no need to take out the center asnd i think that there are 4 or 5 screws holding it on not 3 so thats probley ur problem

 

thanks I'll keep looking

 

I have a 88 formula that I am having problems with the heater control rods staying in place, can I replace the control box and heater core with a later models with electric controls

 

Anything is possible, if you want to put the work into it...

Since you are asking the question I am thinking it may be beyond the work you want to put into it.. Keep in mind that the cables controlled valves and other things that control the air and its distribution. On an electric type, these are replaced with motors or servos and you have to either modify your existing valves with the motors, or find the valves that fit, and possibly modify those. Some of the later cars also used vacuum, and you would have to figure out how to run that too...

Its not a direct fit if that answers your question.

Chances are you have something binding on the control cables causing them not to stay, probably insulation or wires that have been routed incorrectly.