So, I just bought (yesterday) a 1974 convertible, and as a senior citizen am fulfilling a goal I should have reached many years ago in buying a C3 roadster. I have owned several Corvettes in the past, a couple C3's many many years ago (late 70's coupes) and then the infamous '84, then, I think, three, if I recall correctly, late 80's to mid 90's examples, and finally, my last one, a 2003 droptop we bought new and enjoyed for 3 years until very stupidly trading it in for a new 2006 final year SSR. (Please try to stifle your laughter guys!)

Anyway, I always loved the C3 ragtops and on impulse bought a local one offered for sale, a root beer finished auto trans L48. But it's nicely equipped with factory AC and I was extremely pleasantly surprised to discover upon arriving to see the car that the couple selling it had neglected to mention in their ad they also had the matching factory hardtop!

The car needs front and rear bumpers, and the AC isn't blowing cold, but my two "big" questions for you guys are:

1. The driver side window is down and won't go up. The prior owner said the window motor had been replaced about two years ago and because they rarely drove the car (and stored it with the top down and the windows down in their garage) they weren't even aware the window wasn't working until I tested it. Anyway, when I hit the switch and listen very carefully in a very quiet place, I can hear a very faint sound, and I don't know how to describe it....(it's not a "click", more like a very slight "thump" but VERY hard to hear), coming from the inside of the door. I'd love to hear some suggestions on what to do to track down the likely cause of the problem. The prior owners "guess" they may have cycled the window less then a dozen times since the repair.

2. The brakes. Now, as I said, I have owned C3's before, but the last one was over 30 years ago. I don't remember it being so hard to stop the car!! Now, of course I am used to our rather new Genesis G90's instant response to a very light brake, and my 2019 Ram 1500 also stopping with a relatively light touch. Am I just being swayed by what I am used to, rather than what I should expect from a car that is literally a HALF-CENTURY old? The car stops straight, no brake noise of any kind. It just takes what feels like so much more pressure to make it happen! To put it in perspective, it reminds me of my first car, a 1964 Chevy Biscayne that had no PS. no PB, no power ANYTHING. That's how the brakes on this little Vette feel. Normal for this car? I don't remember my past C3's feeling this way, but again, I am old, and my memory of my past C3's are from 30+ years ago and perhaps tainted my what I now drive everyday.

Finally, for now anyway, I was given a binder with receipts from a prior owner which is great! It shows that the AC was converted back in 2001. But the compressor, which is not activating now although all hooked up, (although that can be as simple as loss of freon) still has the old label on it for the old freon type. Shouldn't the mechanic have placed a replacement freon type label on it? How can I determine if in fact the work was actually done? BTW, the fan motor blows VERY weakly even on high. It does modulate even weaker when set on lower settings, so is this what should be expected, (unlike the arctic blast force of my new vehicles), or is this another issue to be fixed?

Looking forward to any advice and/or suggestions you guys can offer!

 

Well,as for the window, I would take the door panel off and see if it is just stuck.
As to the brakes, you don't mention whether or not it has power brakes or not. ( Out of my three one does not) And no, even with power brakes they don't stop quite the same as newer cars.
When the a/c gets changed over usually it's a small sticker placed up on or near the core support. They frequently come off after a few years. The fan motor may need the bearings lubed, after all it's 50 years old.
Congratulations, that's a great looking car!
Welcome from Washington!

 

Thank you for the warm welcome and great advice!

I did find a wire with a plug, not connected to anything and I have no idea where it is supposed to go, coming from the rear under the carpet heading on the driver's side. I need to take a pic and attach it here to see if anyone recognizes it and if it may have some bearing on the issue at hand. I did attempt to remove the door panel and in doing so discovered that the last person in there bre-attached the door handle upside down, so that doesn't fill me with confidence as to his window repair. (I'm assuming that's who did it, since the couple I bought the car from absolutely never attempted to do their own repairs.

After removing the screws at each side of the top of the door panel, (the bottom of the door panel seems to be held on only by velcro type connections, which are already not holding) and the handle I mentioned which also seems to anchor the door panel as well, I ran into tremendous resistance to the panel coming off and opted to not force it for fear of breaking something, since it seems I am missing something holding it on. But yes, since the switch seems to be doing "something" taking off the door panel is the logical next step. I am afraid of damaging it though so want to proceed with caution after getting some advice on just how to remove the panel. What could I be missing?

Btw, I see you ride! I was the founder of the now defunct website "HarleyTalking.com" and before the rise of Facebook, etc, we enjoyed a very active site with lots of great members! Did you ever belong by any chance? Sadly die to health reasons I had to give up riding after 50+ years of enjoying many many MANY different Harleys over the years! It all started with "Easy Rider" (the movie) and the rest was history!

 

I wasn't on that site. Did you remove the door lock ****? They can be a pain.

 

Welcome to the forums and Congratulations, it apears to be a nice straight car. It's had some TLC. True you can't do much with the door with the door panel on. Three screws holding the panel on, 4 if you count the door handle, on the bottom of the door panel there is the one screw about 12ins down from the door latch that needs unscrewed (it clips to the panel,use cation on older panels along with the plastic studs on the bottom of the panel. a small flat crow bar works good for that, I think there are 4 of them, it's been awhile. I had a weird issue awhile back where the window rolled up and down with the door open but it wouldn't roll up when closed, traced it to a broken wire between the door and body spliced the wire and works fine now. Yes pull the panel and do some snooping. Check the brake booster (if it has one) for operation, check brake fluid condition, maybe time for a flush. On the A/C look for oil residue on the line connectors and inspect the condenser, maybe it has a small leak. Has your A/c been updated to the newer dryer receiver? The havc fan has a high speed relay you might check it's operation. The doors on the heater box should be checked for operation that's behind the passenger dash pad. you should check for debre in the heater box outside, by pulling the 2 screws on top of the box, 4 terminal connector will let you check the evaporator area that can slow air flow. I don't think there is one part on my 77 I haven't played with.

 

Welcome to the forum. You can use a panel popper plastic tool to release the plastic type connectors holding the door panel on. Try to slide it as close to the attachment as you can to avoid it popping off of the door panel. When you get it off, check to see if the spring is broken. You can buy a separate spring from aftermarket Corvette suppliers. I happen to be in my car when mine broke and it sounded like somebody shot me. The window would no longer come up though.

What color is the wire in the rear? One possibility would be the wire going to the key switch for the alarm system.

The C3 A/C systems cooling was marginal at best. When converting to R134a, it was even less efficient. Check to make sure that all of the seals around the A/C condenser and radiator are in place and there's not any debris in front of it or in between the radiator and the condenser.

Depending on how deep you want to get into the project, you should get a Factory Service Manual and an Assembly Manual which are available online.

 

Guys, thanks for the tips and the great advice so far! MUCH appreciated! Been busy the last couple days so only had time to take off the driver's side door panel (yes, finally got it off.....I had previously missed that screw on the inside of the door facing the jam)....anyway, looks like the window motor has been replaced as the PO claimed, but the window regulator is quite clearly 50 years old like the rest of the car. I'm pretty sure if it's not the problem it needs to be replaced anyway. Because my patience is limited these days the guy who does all my body work strongly suggested I just leave the window repair for him, and based on many decades of experience, including vintage vettes, I'm gonna take his suggestion rather than frustrate myself with it.
As for the wires I discovered, I "think" they may have been part of the oem radio and speakers, which I did get with the car, in a cardboard box. The oem radio, it's separate amp, and two oval speakers have been replaced by some real garbage aftermarket radio and what looks like little old boombox speakers from the 80's. (So far musical static is what I get from this crap.) Down on my "to-do" list will be replacing that "system", (I use the term VERY loosely) with something that looks like it actually belongs there.

Ya know, as a total aside, I always loved the dark brown metallic and probably allowed that to sway me in my decision to buy this car and pay as much as I did for it, considering it needs both front and rear bumper replacement and several "little" repairs. The matching hard top included along with the like new soft top influenced me as well.
But I'm told brown was an unpopular color in it's day and to this day this color lowers the value as compared to a red or blue example. True or false?
Yes, I know the only opinion of a car that matters is it's owner, BUT, I always like to know what to expect when the inevitable day comes that the car will be moved on to it's next steward.
Thoughts on color vs value? Really curious as to what you guys think!

 

There are those people who will pay more for a car based on its color, but being a roadster with both tops, in very nice condition, I don't think so. At least not a significant amount. I'm curious as to why the bumper covers need to be replaced. How about pictures of the damage? Maybe check with your body guy about repairs?

 

I like brown, it's not my first choice. But it looks good with the buckskin interior. I'm not sure if it would hurt the valve much. It was the last year for the C-3 Roadsters until he 80s, so that's a plus. What color are the tops? I once had a Blue 70 with a white soft top and a Black vinyl hard top. From what I can see from the picture the front bumper has waves in it on the left side. I myself can put up with a lot of waves at $500 a pop for bumpers and the TruFlex are not a lot cheeper.

 

The front bumper cover on my '73 has been slowly dropping pieces on the garage floor over the last 10 years. The pieces are almost as brittle as glass.
I don't recall seeing many '74 brown cars back in the day so I suspect that the take rate on that color was probably less than 10%.