I just finished doing a throttle cable replacement on one of my '74s. There are two big things about these cars that are way different from the later models described in the previous posts, and a bunch of little stuff.
Big thing #1 is good news:
All that talk about bushings and cotter pins and springs and needing a helper and wearing eye protection and what a pain it is messing around with the connection from cable to accelerator pedal.... Forget it. None of it applies to the '74 cars (and Matt Brannon says
it's that way through '78) at all. The throttle cable ends in a single round eye. You slip that eye over a stud on the accelerator pedal, add a washer, and then put a cotter pin or spring clip through the hole in the end of the stud. Once the tunnel cover is off you can see all of this and reach it easily from the passenger side (although as Damon says, it helps to move the console out a bit). It takes about sixty seconds.
Big thing #2 is not so good news:
Chances are that if you are replacing the throttle cable, you're also replacing the sheath it slides in. On all years, this sheath starts at the cambox cover, passes through a cover in the firewall into the spare tire compartment, and then through another cover into the center tunnel with the e-brake, shift linkage, and heater hose. But it doesn't go all the way through the tunnel to the gas pedal; instead the sheath ends at the back of the tunnel, where the fitting at the end slides into a steel tube that carries the throttle cable all the way up to the pedal in front. And on the '74s (and all the way through '78 according to this note
from Chris Obert's catalog) the diameter of that tube is smaller than later models. So the later-model sheath won't work; its nose won't fit into the tube. And the early-model sheath is pretty much NLA/unobtainium. So you use the fitting from the old sheath. Pull it off the old sheath, and thread it with a 1/4-28 tap. Then thread the nose of the new fitting with a matching die (I cut a half inch off the nose first) and you can screw the old fitting onto the end of the new sheath... and now you a have a sheath that will fit properly into the tube.
Once that's done, the whole thing is really easy.
- You've already removed the tunnel cover and the parking brake lever to get the old cable and sheath out. I removed the passenger side seat because it only takes a moment and makes the whole job more pleasant. If you have a '74, you'll also have to disconnect the choke cable from its lever - but because the new cable sheath goes through all the same openings as the choke cable, it's still easier.
- Feed the new sheath into the engine compartment from the spare tire well. You do not have to remove the cover in the firewall; just push the sheath on through.
- Hook the eye of the new cable up to the stud on the gas pedal. Insert the cotter pin from the rear towards the front; this will make it a lot easier to get it out next time.
- Feed the end of the cable through the rubber grommet on the front end of the tube. At least on my '74, there was no need to remove the grommet; the cable end went through just fine. Keep feeding until the cable comes out the back of the tube.
- When it does, start the end into the sheath, and keep feeding.
- Eventually the end of the cable will emerge from the engine end of the sheath. Grab it and pull it the rest of the way through.
- Now you can slide that threaded-together sheath end into the tube and replace the spring clip that holds it in place. (If reaching back into the tube from the e-brake opening is too awkward, there is an access hole right above the clip, but it's under the carpeting behind the e-brake, and to get the carpeting out of the way you have to remove both inboard seat belts - not worth the effort, I think).