I had a similar problem replacing the clutch cable adjuster on a 1985 Mustang GT. In the Chevette I used to have, it was about a five-minute job. On the Mustang, I couldn't even find the adjuster. I took it to my mechanic, who charged me eight-hours labor to replace it. It turned out you have to remove the steering column to replace the clutch cable adjuster.
There may be a little hope in some areas. When they started putting all sorts of controls on the turn signal lever, it meant that if your turn signal lever broke off, it was a several-hundred-dollar repair, since there were a bunch of wires running through the lever and down the steering column. Now that various parts of the car are communicating via CAN bus or LIN bus, there are not as many wires needed (one, in the case of a LIN bus), so the replacement cost may be somewhat less.
The cooling systems on modern cars are highly dependent on having the proper coolant, and changing the coolant as specified. My brother, a lifetime auto mechanic, says to change the coolant more often than recommended. Modern aluminum heater cores (and other components) won't last long if the coolant is beyond its life. Coolant beyond its life will cause rapid corrosion. Also, never use or add the incorrect coolant.
I think it's the case for everything on newer modern cars, do the preventative maintenance as specified in the owner's manual, or pay the (expensive) price later.
Yes, I've changed heater cores on older cars I had years ago (1970's & 1980's)...so I personally know how hard heater cores can be to change. I've not had any problems with the heater cores on my late model cars (late 1990's and newer). I recently had to change a radiator in my 1998 Camaro, but that was due to a cracked plastic side tank, not corrosion to the aluminum radiator element.
I had the same problem with my 96' T-bird, but I did fix it. The A/C always leaked after that and I wasn't going to go through the mess again to fix it. I bought a new vehicle as soon as spring arrived.
I owned a 96' Thunderbird and worked on other 90s T-bird and Cougers as a mechanic during college. The Ford heater cores were too large to come out under the dash or through the glove compartment. Teh only option was to detach the dash assembly from the firewall and squeeze the core in and out from the top.
Probably worked well for producability in a factory, but it was a dreded repair for mechanics. Removing the dash is easy in theory, but is extremely difficult in practice to get to all the connectors and fasteners that need to be undone. You would think that if dash removal is required, engineers would make the dash removal easier!
Slightly off topic, but it's not just cars either. I just had the alternator belt replaced on my Cessna 172. You have to remove the prop to get the belt on, imagine the labor hours in that! My mechanic told me that they typically put an extra belt on and zip-tie it to the engine to sort of cut the labor in half. The two belts should last until the next overhaul.
Yeah, not new. I had a '69 Cutlass that had a similar leak. Went to the library and dug this out of the Motors Repair manual: "Begin by removing the right front fender". We were able to get access by only removing the plastic inner fender liner though.
I've had a 1969 Chevy C10 pickup for 25 years (345k miles on it now). When the heater core went out in it, I found it enclosed in a fiberglass assembly on the firewall, wedged behind the inner fender well. Not looking forward to removing the front sheet metal, I used a dremel to cut the fiberglass vertically next to the core. there were enough mounting holes that each half is fully supported.
Now I can easily remove and install the core as needed, just need to reseal the cut with silicon.
Yes, as others have noted, and for many years, it seems the majority of cars have been built by first laying down the heater core and then constructing the rest of the car around it. If only the cores were more reliable...no one would notice!
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