Front frame repair

[hogie]

I have a new plan....I fill it back full of foam cover it with a small riveted in plate and sell it as proffessionally rust repaired!

Ok, my ethics would prevent that...

I really dont think it would be too hard to open up what is left and fill it with a 2x3 box tubing. Though it will be far from factory looking.

[Carl Beck]

Hi Hogie:

I may be looking at the pictures all wrong - but it seems that your Frame Rail is fine - it is the lower part of the inner-fender, that forms the outside of the "box" to complete the structure of the frame rail - that has rusted away.

I'd certainly clean the rust out of the frame rail itself - and treat it to prevent farther damage. Then I don't see any reason why you could not just cut the inner-fender back to a point where you have solid metal, then weld in a patch.

Replacing the frame rail with a new OEM part - still would not correct the damage to the inner-fender.

FWIW,

Carl B.

[hogie]

The frame rail is compromised, but not to the extent that the inner fender is. It suprsises me that this area isnt built any better.

I have tried to add a 3d's outline of where the damage is. The green line represents the lower outside edge (inner fender bottom). Red = damage....on the passenger side it only creeps up half way. On the inner fender edge it climps ot the top of where the frame rail welds on per carl's diagram. I need to pull off the angle iron to be sure though.

[stevef1972z]

I understand your situation and have a similar problem myself and recieved the same advice that you are getting. Living here in the heart of the Rust Belt, anything older than 15 years has rust. Replacing floors and framerails is standard work here for any Rustang or Camaro, and definitely on a 240z. Out West they part them out. The advice is solid, depending on skills and use of the car.

I went down and removed all of the undercoating in the area. Then I went through a very complete and brutal evaluation of the area. I cut out all of the rust, heartlessly. After that I knew what was looking at. I then bought several sheets of poster board and made patterns of the area that was to be replace. I bought a 4x4ft sheet of 18 guage to make the parts. I will bend them this weekend and start getting them welded into place. (if you dont have a sheet metal bender, you can rent one, or farm that work out with the patterns that you made) I will add a piece like the Bad Dog upgrade for the suspension mounts.

It can be done, to make the car safe and fun to drive. It depends on how much work you want to do. My car will not look factory, but lets face it, if it is a high number car with milage on it, its really not worth that much on the market. Parting out is time consuming as is selling all the stuff if there are not many Z cars in the area. It depends on what you want to do with the car, your skill level, and how much sweat you want to put into it.

For me, working on cars is half the fun, if I wanted to just drive something I would have bought a Miata.

Good luck on whatever choice you make.

[Carl Beck]

Actually the front frame rails carry very little weight. The weight of the engine is carried by the front cross member to the to the strut and strut tower. Most of the weight of the body on the front suspension is carried by the upper fender horns. The front frame rails main load, other than at the strut towers - is fore/aft.

So strength is needed primarily in the area between the front frame rail and the strut tower.

Again, I see no reason a properly welded in sheet-metal section, to replace the original - would pose any problem at all. I wouldn't recommend a butt joint - but rather a piece of metal welded inside the frame rail where you have solid metal - overlapped with the new exterior piece. That way you would have the needed strength with acceptable cosmetics. Just be sure to tie the frame rail to the strut tower - by fixing the inner-fender.

Should be an easy fix for experienced welders/metal workers.

FWIW,

Carl B.

[=Enigma=]

I'm no expert on this by any means, but based on all that's been said by you and everyone else I say go for it. Just do whatever work you're capable of and seek help for that which you aren't. In the end, you'll have a fun, drivable car that you can enjoy. As I see it, this is one more Z saved from the crusher!

[hogie]

I figure the strut towers would carry alot of the load. However I would think that cross member mount would have to handle cornering forces and at least a bit of twist from the engine.

Either way I am a bit less worrried now.The other thing Is would it be wrong to assume the front end is square still? The front radiator support is solid. Does anyone have the frame dimensions for our cars? I found the one in the FSM and it is essentially unreadable.

THanks

Edited June 9, 2009 by hogie

[ggarrard]

Hogie -Sorry I can't help out with dimensions, but unless you'v noted large body panel gaps, or signs of accident repair, you could start with confirming your car is square by measuring the open "box" of the engine bay. Patching the inner fender and the frame rails is doable - it's only sheet metal on the Z... You're on the right track...

Regards

GWGarrard

[hogie]

Well, I guess it is time to get the engine back out of it then. Though, I guess technically I didnt have it out the first time, but I did get everything hooked back up!

It may be possible to weld this up without pulling the engine. i am sure that will be harder though.

The panels actually fit quite well for now, but the previous owner got those set-up.

[geezer]

Am I missing something here? Looking at these pictures, starting with the first one, I see the rail distorting out of shape by just sitting on a jackstand. I really would like to see some pics with the angle iron removed. It's bolted on and fastened to the inner fender with aluminum rivets and has to come off anyhow. I don't think there is enough good original metal left intact to properly piece back together. Why not do it right and replace the rail, whether using the one available from Zedfindings or using square tubing? At least you could be assured of gaining the nessesary structural strength that would be a lasting repair. Any car I've seen with this much rust damage in this area, had much more unseen rust deterioration just below the surface throughout the entire vehicle. Couple that fact with the doctored repair work you have uncovered, its not a stretch to think more surprises are in store.

This is not a pessimist attitude, but rather a realistic viewpoint.

[hogie]

Yes, you do see a bit of distortion in the angle iron at the jack stands. I have since moved them to just behind the tension rod brackets and they are a bit more straight now.

Does anyone have a proper method of locating exactly where the crossmember mounting holes should be in relation to the front of the frame? Since they half arsed this part, I doubt they properly positioned it.

Knowing my friends it will end up with square tubing as opposed to sheet metal. We will see how much worse it is when I get that angle Iron out.

[John Coffey]

My opinion above was based on time vs. money. If you've got lots of time and want to tackle this project, go for it.

A big issue will be getting clean metal to weld to. Anything touched by the foam needs to removed. There really isn't a solvent that can clean Urethane based foam off of metal good enough to allow a clean weld. Maybe MEK but you'll still have some residue that will screw up part of the work. And breathing burning MEK will make your **** turn green and fall off. :-)

Edited June 9, 2009 by John Coffey