I'M a newbie to this site and looking forward to the questions and answers here. I have a 71 olds cutlass s I bought in 1972 and has never given me any problems until recently the heater core started to leak. I have ordered a new one. How do you go about replacing it, I've heard several opinions.
Thanks

 

Welcome.

Opinions on replacing a heater core???

This is what the 1971 Oldsmobile Chassis Service Manual says, good book to have if you want to know anything about or work on the car, "The Bible".
No opinions, just the facts.

This is for without AC but basically the same deal, you have to take the heater case off to get to the heater core no matter what.

"Core Assembly

The heater core is located in and attached to the heater.
To remove the core drain radiator, disconnect heater hoses and remove the five attaching nuts.

To remove the right lower attaching nut, it will ne necessary to disconnect the right fender at the bottom an block away from body then remove retaining nut thorough this opening.

Disconnect the resistor wiring, the three control cables and and remove the case assembly from the dash panel."



Be very careful with the nipples when you put the hoses back on, easily broken. I use a little permatex on the fittings to make the hoses slide on easier and it helps seal them, heat up the hose ends in hot water to help them stretch around it, don't forget the clamps. When removing I always cut off the hose then slit those heater hoses hunks on the fitting lengthwise and peel them off , never attempt to twist or pull them off.

 

Welcome to the site! I moved your thread from the site suggestions location to the newbie forum. I believe there may be some old threads on this if you have the time try the search option to see what you find. The last time I did it I put the car on stands, removed the right front tire and inner fenderwell to access the underhood portion of the heater/AC setup. If you have rusty bolts it may be hard to get the inner fenderwell loose, but if you can this will make everything easier to reach. You have to remove the nuts from the engine compartment side to allow you to remove the heater box from under the dash. The heater core is inside the portion under the dash. Be careful with the control cables running from the dash panel to the heater box. And expect to spill some antifreeze inside the car... which may not be a big deal if it's already leaked in there! If you haven't picked up a Chassis Service Manual for your year I'd strongly encourage it. I've used mine time and time again and it will have detailed drawings and pictures of various repairs like this. Good Luck with your repair, and if you get hung up post a question on where your at. John

 

Welcome to CO. That hardware is difficult to get too even after loosening the inner fender, at least it has been for me, my arms and hands are kind of large. Good luck.

 

Good luck with your heater core replacement. I am facing the same thing on my 57 Olds

 

Hi and Welcome to our site!!