64, 60 Special Heater Core Replacement.

[Louis J. DeMatteo]

Thank Heavens I've just finished it. What a nightmare.

Discovered the car had no heat while an attempt at a Thanksgiving Dinner at my wife's aunts house in Connecticut. No heat meant we used the 09 CTS4.

      I removed the 2 heater hoses from the fire wall and tried blowing through the core. Very little to no air or coolant came out. Also noticed that the previous owner had issues with the pipe that runs under the intake manifold to the 5/8" end of the core. It appears to have rotted out so they simply cut the bad section out and coupled it with a hose. Didn't look very good. I initially thought of using a long piece of Heavy Duty Marine Hose with the wire reinforcement in it then realized that the metal tube is there for a reason. Imagine the heat generated under that intake manifold when the Heat Riser Valve is Closed and the Very Hot Exhaust Gases are now passing right over that pipe. I would imagine that it would melt a hose. So I picked up a 24 inch piece of 3/4" stainless tube which was fairly easy to get {I googled it} and bent it up the way it should and replaced the bad one. Had to double strap each end as I had no way of hose flaring the tubing. I wouldn't recommend bypassing it. Also replaced that pre-molded hose from the water pump. That wasn't easy to find. I believe the one I bought was meant for a Chrysler. It fits fine. Pain staking search on Gates Hoses Web site.

 Now to the core. First, the new, hidden sound system in the glove box had to come out. That in itself caused major anxiety. Then the glove box and so on. Service manual was handy to a degree. It left out a couple of key removal points that I discovered on my own. Lots of duct work to remove. Vacuums lines to disconnect, Door cables etc. You can see why these jobs are so expensive. Only problem with letting someone else do this job is you know they are not going to put everything back the way it should. The temptation to cut corners is too great, and its my car. I took my time, scratched my head. Banged my head. Even got my head stuck under the dash once. Picture this. I am about 5' 11", 285 lbs, 53 years old and found myself in positions that Cirque du Soleil would be proud of. Head under dash on my back with my feet dangling over the passenger seat back into the rear seat area. I know, not a pretty site.

  I bought Cadillac Tim's manual {http://cadillactim.com/page1.html}, a must have if you own this car. When I spoke to Tim he gave me a heads up to check or replaced the Vacuum Control Door Actuator that's in the heater box. Made lots of sense. If it doesn't work you'll only have to do this entire job again. I applied vacuum to the unit and it worked perfectly. Applied vacuum to it and left it that way overnight and it didn't leak. The 50 year old gasket around the door was dried out so I replaced that. Thanks Tim.

  Now that the New Core is in its new home, after a careful pressure test prior to install. {Imagine installing a new one and your significant other gets coolant on her new pumps?} Putting the Heater box back in was indeed a challenge. It would have been easier with another person. Jason, where are you when we need you? Aligning the heater box with the heavy rubber duct from the evaporator while trying to line up the 6 studs and the 2 tubes through their perspective holes was.............interesting. Lots of fun words flying around my garage that day. 

  With everything in place, the Sound System had to go back in. That required a visit to the guy who installed it. He knew which wires went where. It was easier that way.

   I wouldn't wish this job on anyone. This is the third Heater Core I've changed in my lifetime. One was in my 88 Bonneville SSE the other was 3 years ago in my 76 Eldorado Convertible. This was the 2nd Heater Core for the Eldo while I own it. I let my mechanic do the first one. Hmmm. The dash sounded like he left a babies rattle in there. When I did the second one myself was when I discovered quite a few bolts were missing. Installed an aluminum core this time and put all the right bolts {had to find new ones} where they belong. No rattling dash now.

Well, now the old girl is back to her spiffy self. I just thought I would share this experience. I know a lot of guys don't bother replacing the core and live without the heat. My baby has only 39,000 miles on her and she deserves the attention.

[Louis J. DeMatteo]

I wondering if the crimped end wasn't to restrict flow slightly.

[Robert Alan Shannon]

Louis, enjoyed your post; I went thru that years ago, brought back some memories. My parts car also has the 5/8" tube crimped down into a square opening. Kinda interesting. I don't remember if it was that way on the core I replaced though.

[Louis J. DeMatteo]

Oh, I have a question.

I noticed that the factory heater core that was clogged up had the 5/8" end was slightly crimped making the opening smaller. Was that deliberate? The replacement core didn't have that.