Heater Core Problems
jogoff69
12-23-2005, 04:08 AM
I have a blown heater core in my 91 Caprice Classic 305. I am attempting to save a couple hundred bucks by doing the job myself. I was told the heater core is inside the car, behind the dash, on the passenger side. I already have the part, so I know what I'm looking for. I have a lot of the dash taken apart, and I still don't see it. Is there anyone that can give me a little more detail on what I'm doing, and any problems I may run into. I live in Chicago, so it's cold. I also was trying to judge where the heater core was by where the hoses entered the car through the firewall, and I noticed I'm missing a hose that I believe is supposed to go to the heater core. It is low on the passenger side of the car, entering the firewall. There is a little coolant leaking out of the hole where it is supposed to be. I have no idea where this hose is supposed to go to, I see nothing else "un-hooked." Any help will be appreciated.
RageCage
12-23-2005, 07:40 PM
<< I have a blown heater core in my 91 Caprice Classic 305. I am attempting to save a couple hundred bucks by doing the job myself. I was told the heater core is inside the car, behind the dash, on the passenger side. I already have the part, so I know what I'm looking for. I have a lot of the dash taken apart, and I still don't see it. Is there anyone that can give me a little more detail on what I'm doing, and any problems I may run into. I live in Chicago, so it's cold. I also was trying to judge where the heater core was by where the hoses entered the car through the firewall, and I noticed I'm missing a hose that I believe is supposed to go to the heater core. It is low on the passenger side of the car, entering the firewall. There is a little coolant leaking out of the hole where it is supposed to be. I have no idea where this hose is supposed to go to, I see nothing else "un-hooked." Any help will be appreciated. >>
Does the new heater core have the two pipes approximately next to each other? That's how they are on my '85. If so, your hose that goes in low on the pass side is something else, I suppose.
On my '85 I was able to get to the heater core from the engine compartment, no need for crawling around. I removed the leaf guard and some other stuff that went around the a/c tubes, on the passenger side, and was able to pull out the old core and put in the new one. It took me about 4 or 5 hours, but it's really just a 1 hour job for a skilled mechanic, at least on my '85 305.
Be gentle putting in the new core, and attaching the hoses. They are weak around the welds that connect the inlet/outlet pipes to the core.
Good luck.
Does the new heater core have the two pipes approximately next to each other? That's how they are on my '85. If so, your hose that goes in low on the pass side is something else, I suppose.
On my '85 I was able to get to the heater core from the engine compartment, no need for crawling around. I removed the leaf guard and some other stuff that went around the a/c tubes, on the passenger side, and was able to pull out the old core and put in the new one. It took me about 4 or 5 hours, but it's really just a 1 hour job for a skilled mechanic, at least on my '85 305.
Be gentle putting in the new core, and attaching the hoses. They are weak around the welds that connect the inlet/outlet pipes to the core.
Good luck.
Blazin_Jason
12-26-2005, 05:48 PM
I dunno where they are in the newer cars, but my 80 was an easy swap out. As mentioned be carefull with the new unit. I actually added more solder to mine just in case. Best bet is to get a Haynes/Chilton book for your car.
Jason
Jason
jogoff69
01-02-2006, 04:10 AM
I just bought the Haynes book showing how to so the job. I'm still a little confused. The book shows a few diagrams, but is not real specific. It says the heater core is inside the car, on the passenger side, behind the dash. I removed almost the entire dash, and still can't find the heater core. Is there anyone that has done this before, and may know something I don't. If I don't get this done soon I'm gonna freeze to death. I appreciate everyone that has posted so far, but I think my 91 is a little different. Thanks for the help.
TommySS
01-02-2006, 09:39 PM
Haynes gives you just enough info to get into a lot of trouble - use the factory manual (Helms)and you'll be fine.
bobss396
01-03-2006, 08:49 AM
Most libraries have a set of shop manuals in the reference section. You'll probably have to make copies, they don't let them out of the library.
I agree that the Haynes manuals are virtually worthless, who needs a diagram of a '64 Chevy tailgate in a '90 edition manual?
Bob
I agree that the Haynes manuals are virtually worthless, who needs a diagram of a '64 Chevy tailgate in a '90 edition manual?
Bob
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