Heater cores are aluminum now??

Bought a 1973 Chevy C20 pickup five years ago as a birthday present for myself.
350 V8, 4-speed and an 8-foot bed to actually haul stuff with. A 4x8 anything will fit in the bed with the tailgate closed!

Got tired of all the computers and electronics in the last truck I had. 2001 F250, every time the engine light would come on it was always $200+ to fix it, always a sensor or sensor related thingamajiggy that had nothing to do with the truck running good, just government junk that would keep you from passing emissions tests.

Any hoo, for the last year Bertie (wife named her) has had a mysterious coolant leak. We use her on the weekends around town and for an occasional trip to work, depending on the weather. Nothing over 25-35 miles each trip, she's geared for pulling not hi way cruising.
I always check the oil and coolant levels before an outing, something I have done since I was a kid.

Always needed a half gallon or more of antifreeze to Bertie before each trip, found a small drip at a coolant line on the intake last month and fixed that thinking that was the problem, nope!

Yesterday the leak revealed itself, started her up to let her warm up before our trip, came out ten minuets later to go and I saw a drip and a small puddle on the ground under the passenger side floor board area. Popped the hood thinking a coolant line at the heater core, nope antifreeze was trickling out the bottom seal of the heater core cover. Funny thing is the carpet and floor board inside the cab are dry as a bone. Shut her down and took the suby to finish out our errands.

Once home I looked online for a replacement, what the ?? there all made of aluminum now, 100% aluminum?? And the notes on most of these say some fitting required?? What's that about? Not a bolt in anymore?? I know the new cars, (to me) 1985 and up have plastic and aluminum radiators and have replaced a few in my day but never seen an aluminum heater core. And The last time I replaced a heater core was back in the early 90's in a 69 mercury cougar and its replacement was brass and copper and it fit right in, no fitting required!

I'll probably have to replace it with an aluminum one, fine. But I don't get the "some fitting required" thing they have in the notes. Not wanting to butcher Bertie.

Guess I'm too old school in my ways anymore. Just kind of threw me for a loop when I looked for a replacement and found there aluminum and not good old copper and brass.

Attachment 324982

Might be a good excuse to get a small oxy/ecy torch and learn how to solder/sweat brass and copper.

Might be able to find the leak and fix the old core.

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If your f250truck heater/ evaporator box is setup similar to the econoline e150/e250/e350 vans with the big black plastic box that houses it all as an assembly you are in for a world of fun, gotta decompress the ac to remove the box. Get the seal kit, bunch of o-rings, so you don't have to do it again in 3 years, replace the actuator vacuum hose while you have access. The location of the bolts is really stupid but if you have a good 1/4 drive ratchet set you will knock it out just fine.

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Originally Posted by Joe504

Might be a good excuse to get a small oxy/ecy torch and learn how to solder/sweat brass and copper.

Might be able to find the leak and fix the old core.

Sent from my SM-N970U using Tapatalk

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Done that on the last old car we had, hoping once I get the core out I can fix it. The way it was leaking I'm guessing it just might be a rubbed through supply line or joint at the core.

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Originally Posted by Recycled bullet

If your f250truck heater/ evaporator box is setup similar to the econoline e150/e250/e350 vans with the big black plastic box that houses it all as an assembly you are in for a world of fun, gotta decompress the ac to remove the box. Get the seal kit, bunch of o-rings, so you don't have to do it again in 3 years, replace the actuator vacuum hose while you have access. The location of the bolts is really stupid but if you have a good 1/4 drive ratchet set you will knock it out just fine.

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My dad had a 71 E350 when I was a kid. He had to remove the whole dash to get that heater core out.
That was the day I learned all the bad words! :)

I was a parts sales person at a dealership for 15 years. I quit in the year 2000. Heater cores had been original equipment for a few years before I quit.

They've been aluminum a long time

It shouldnt be to bad but may be more work just getting to it. Its probably a joint thats been rubbed or flexed and should solder up fine. The big thing is getting the joint clean and dry to solder. It will probably be more work running the leak down and prepping it.

Not sure where you are at but here almost all the "junk yards" are gone,where you could buy used parts cheaper.

I spent forty years working for GM, Ford, and the aftermarket making climate control products. Heater cores have been aluminum for going on forty years now. If your copper/brass heater core lasted since it was new I’d be surprised. I’m betting it’s a replacement that’s leaking. Anyway, that “some fitting required” usually doesn’t amount to too much. Most of the time if it’s not a direct replacement you get the parts you need to put it in. Aluminum radiators and heater cores are light years ahead of copper/brass for reliability. FWIW, I worked as a quality engineer, quality manager, and operations manager. I’ve seen millions of radiators and heater cores. Been retired now for around twenty years.

lmc truck or brothers truck both have drop in replacements, currently redoing a 78, 82 and 87 so lmc has been getting a lot of money from me and they most always are cheeper

https://www.lmctruck.com/mechanical/...er-motor-parts

I have found that aluminum heater and radiators are much more efficient than the copper ones. I am an old school master mechanic and I fought the trend for years until the radiator went out in my big block powered motor home. I had to go with aluminum and I found that it cools a LOT better than the copper. I have since had to replace the radiator in my Dodge diesel and Ford F350, all aluminum and all much better than the original. As far as fit, most heater cores do not bolt in, they are held by foam mounts inside the box. I have done older Chevy pickups but I do not remember what holds them in since it has been 20 years since I did one.

I worked in an industrial radiator factory in the early '70's. Aluminum was the rule of the day for the big heavy equipment radiators. Some weighed over 400#, so weight was an issue.

Heater core + GM= remove dash, cables, wires, and half the crap on the fire wall in the engine well, aluminum core $29, shop time $600-$1k. Atypical. Mine poured coolant out on the inside passenger floor when a core seam split. Screwed up half the carpet to boot.
Just try to change a left front headlight bulb in a 09 GM PU. Involves the left front fender or removal of the entire front grill. No one ever accused GM engineers of giving a flying doughnut about repair or even changing a tire. Like the corvette they made that required the left rear fender be removed to change a left rear flat tire.
Problem with aluminum and fixing a leak, is that by the time it leaks, the entire mess is rotten. Had thousands of AC units on the beach go out, real early when the mfgs changed to cheap aluminum compressor cores and then to cheaper Chinese parts. 20 years went to 5, if lucky, more history of junk.

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Originally Posted by rancher1913

lmc truck or brothers truck both have drop in replacements, currently redoing a 78, 82 and 87 so lmc has been getting a lot of money from me and they most always are cheeper

https://www.lmctruck.com/mechanical/...er-motor-parts

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Bought stuff from them, always good. Yea they have the core for less than $40. Going to pull mine first and see where the leaks at and go from there.

As long as you don't have air conditioning in your truck, it shouldn't be too awful bad to change the heater core. Most of the ones I have replaced have been in Ford pickups, and as the trucks got newer the job got easier.

Robert

Bought a used 3/4 ton pick up from a uncle the year Nixon resigned. That fall my mother and an aunt delivered it from Michigan to So California. On the way out the heater core started to leak. Weather was warm enough so the just had mechanic by pass heater. Mother and aunt were on their way to Australia and New Zeeland. I had great fun getting heater cover off the firewall. GW put bolts all over the place. Once I got the cover off it was no big deal to replace the heater core. Put cover back on with about 3/4 of the bolts. Lasted about 20 years till I sold the truck.

sometimes the engineers do you a favor. easiest heater core I ever did was my 1988 Bronco II. had a thing called the heater core access door under the dash. very simple job on that one.
Barry

In the real old days, heater core was in a separate box, inside on the firewall. Early fords had the heater box under the hood.

I put a heater core in my 1987 GMC 4x4 with a/c. I removed the glove box and went in, it was a pretty simple job . I had a 73 chevy 4x4 but never had to put a heater core in it. Nice looking 73 you have there I don't think your 73 will be a bad job at all to install a heater core.

The GM Seal tabs are one of the best coolant system sealers out there. They are dry pellets put into the system. Just added them as part of the job when doing a water pump or cross-over gaskets on Northstars and I did a lot of them.

Think it was our '81 F150 shop truck?

Heater core can be accessed from engine bay by cutting the housing open. New sheet metal flat cover,RTV and self tapping screws to finish. About 20 minutes or so.

Jeep CJ, take passenger side door off and everything is right there in front of you bolted to the inside of the dash. Can have it out in 5 minutes. Probably faster with todays battery powered tools.

I have had several square body Chevies and the oldest had a brass core and I replaced it with one but it started leaking a third time before I got rid of it and the loas one was aluminum. Not as bad to replace as it sounds, a battery drill or driver speeds it up a lot.

One thing you need to check with heater cores is electrolysis, If you have a bad ground on the engine then voltage will pass to the heater core and etch it out quickly. Chevies had a big problem with this. Also need to be sure the core is grounded and the blower is grounded.

Carrier has an aluminum outlet tube from their condenser.
We want to stop r-22 at 250#
So Carrier sends JBWeld with a part number, expensive epoxy.
slide copper into aluminum greased by JBWeld
works for me.

Just replaced the radiator in a ‘95 Dodge Cummins diesel truck, 530,000 plus miles, on it. OEM radiator was brass core, plastic tanks. NEW radiator was aluminum cores, plastic tanks. Heater core we replaced 4 years ago was an aluminum core replacement! It runs cooler, by the way!

You might research different types of anti-freeze if you install that aluminum heater core. I think the old school green kind became obsolete, because of aluminum parts.