Cj5 rusted frame repair

[Vibe guy]

I have a 1974 CJ5 that is getting a fiberglass body. It has some rust issues with the frame. The body mount location just above the lr spring mount is rusted through and broken. The frame lower rail is also very thin at the spring mount and jounce bumpers, and is rusted through at lr shackle mount. I'm thinking of replacing the lr section at shackle and welding flat stock on thin areas. Unsure whether its better to cut out sections and weld in repair pieces on top or bottom rails to eliminate rust build up between new and old or just put a patch over it and weld in place. Any advice from a voice of experience would be appreciated. Thanks!

 

[Hedgehog]

There comes a time when a replacement frame is the best move you can make. I've always heard that it's tricky business to weld a frame.

 

[tarry99]

I have a 1974 CJ5 that is getting a fiberglass body. It has some rust issues with the frame. The body mount location just above the lr spring mount is rusted through and broken. The frame lower rail is also very thin at the spring mount and jounce bumpers, and is rusted through at lr shackle mount. I'm thinking of replacing the lr section at shackle and welding flat stock on thin areas. Unsure whether its better to cut out sections and weld in repair pieces on top or bottom rails to eliminate rust build up between new and old or just put a patch over it and weld in place. Any advice from a voice of experience would be appreciated. Thanks!

The amount of rust is what is important................basically you have to have firm good steel to weld to otherwise you are just wasting your time. That may require adding a section of frame just to get back to something that is strong enough to weld to and support the weight & stress.
I would suggest that you take this to a competent welder and ask there opinion...........no one hear could give good advice without first seeing all or the extent of the damage.

 

[73CJ]

Boxing and replacing sections can add years. How good a welder are you and how much time do you have to spend?

Mild trails and street use, sure. They're getting harder to find for the intermediates. Only 4 years.

Many articles on the net about fabricating new frames.

Time vs money.

 

[S76]

I just had a similar exercise on my CJ7 frame. A long time was spent trying to figure out the best way to do this. In the end, I cut out the bad sections and made duplicate pieces that were welded in flush. Then I put doublers over those areas so they extended well past into good metal. Overall I am sure it is stronger than new. But it took a long time.

Your frame is junk as it is. So if I were you, I would get a thin cut off wheel on a 4" grinder and little by little cut out the bad spots, moving further out until you get to good metal. Then you will have a good idea of what you have to work with. If you can tackle it, fine. Or maybe a good welder can do it for you. But whatever the case may be the thin rusty spots have to be removed. Then take it from there.