Hey guys, been lurking here since before I bought my car and finally decided to join. Always wanted c3 and finally purchased a 75 vette and have been having a blast driving it. I currently have the door off replacing hinge pins and bushings, as my doors sag (bushings are shot), and decided to remove kick panels and take a look. I naively assumed while looking at the car, that a good frame meant a good birdcage, I now know that not to be true. I know this post is overdone but obviously all circumstances are unique so I was hoping I could get some feedback on what I’ve found. Hoping I can clean/Dremel these areas and possibly paint with POR and continue enjoying the car. It stays in the garage and out of the rain. I am not capable or financially able to remove the body at this point. I just bought it hoping to be a fun driver. I know a 75 is not generally worth any extravagant repairs but I do love the car and would like to hold on to it. Thanks in advance for any advice!

Drivers side

Drivers side

Passenger side mount looks in better shape but appears to have been treated at some point?

Best photo I could get looking up passenger side #2 channel

This is what really worries me. Looking up under the car around #2 mount on drivers side. Passenger looks similar. Appears to be surface rust up the rockers except for right around these mounts

 

paint it up and enjoy the car. no dukes of hazzard style driving...

 

Thanks for the feedback. Does that rocker rust looking from under the car seem pretty significant/beyond fixing?

 

Had a 76 and yes, we had the most fun with it, our first C3.

IMO, I would do the following:
*check the frame carefully and search forum here for rust issues to understand more.
*rust expands 7 or 8 times original metal thickness so always looks bad, poke the frame where accessible with a screwdriver and see if you have good base metal, if you can poke through rust holes, I say you need to cut back to good metal and weld repair
*check the windshield frame carefully, sometimes you get rust holes under the glass that are hard to see. pulling the windshield out tells you for sure. But lots of C2 and C3 owners have small holes under glass and do not know it.
*See if the windshield frame flexes if you moderately push on it.
*if the doors sag, is it the hinge bushings or rust in the door frame area.
*Provided you think you have some solid metal and it is mostly surface rust, I like Walmart Rustoleum rust converter and spray in frame and up front door pillars above #2 body mounts. Eastwood makes a frame spray with a little plastic tube and spray nozzle that you can spray a lot of internal places. I adapted the Eastwood sprayer to the Rustoleum cans and did more.
*jack up on 4 points GM says to use and see if your door gaps change much, in other words, how is the frame flexing.
*get a HF remote viewing camera and see if you can see more.
Hope this helps and good luck.

I would poke the areas in your photos with a sharp screwdriver by hand and see if all surface rust. This area collects the rust flakes from a sizable area above, so hopefully it just looks bad. The bolt head looks pretty distinct which I think is good, seen worse!

 

Thanks for the response and a ton of good info. I will follow through and hope for the best. The car checked too many boxes for me to pass on and I’m just hoping I made the right choice. I want it to be safe for my girlfriend and I to cruise in

Although they have some light surface rust the hinges seem solid. I was worried the sagging was birdcage-related but I believe it’s just these nearly disintegrated bushings

 

hinge bushings are definitely the door sag issue. https://www.corvetteforum.com/forums...orvette-6.html roll down to post 107 and read. this is mainly what to look for to avoid buying a car like you got. but also helps show what to look for so you know what you got. i assume you did not pay top dollar for this car. since you don't seem totally heartbroken over the condition. clean out the junk in the 2 number 2 mounts and see how bad they really are. body off frame is not enough for doing this repair correctly. birdcage out of body is also usually needed. 3 bay garage and a year minimum. virtually no 75-79 corvettes can justify this expense and amount of work. hell, very few 68-72 corvettes justify this much.

 

Thank you. I’ll clean it up and see what I actually have. No I did not pay top dollar but I would be heartbroken if the car was not worthy of putting some time/money into. Has a brand new crate motor, rebuilt 4 speed, new paint, tires, exhaust, and I would love to overhaul the suspension. Anyway, here she is…

 

Clean those areas up the best you can without removing any mount bolts and coat with POR-15 or similar product. Enjoy the car as is.

 

every component you bolt into it can be unbolted and installed in a better body when one falls in your lap with mechanical issues or no engine issues.suspension and brakes are must-do if it is a driver. and in the mean time, if you don't shine a flashlight on the nasty parts, they don't show...

 

Vacuum the loose stuff…leave it..its not going to rust more without moisture..

drive it..

 

Nice Corvette! I like it, Steel Blue?

 

Agree, but if you pull the door up and down, does the metal body post that the door hinge is attached to flex much?

And thought for you, if you have a Corvette club in the area, you might join which is fun, and you might could locate a knowledgeable C3 guy in your area who would be happy to look it over for a case of their favorite brew (My Corvette friends currency of choice!). Agree, what you want to know, is the frame safe to drive? Hoping for the best.

 

Thank you. Yes Steel Blue, hard to believe so few were ordered in this color. I think it looks great

 

The body post feels solid, so I’m hoping I have more good news than bad. I’m in Delaware and there is a corvette club here I’ve thought of joining, and beer currency is my favorite form of currency. Thanks!

 

Put a roll bar in it and drive it......................