Rear frame rail replacement - advice needed

[TT from NH]

My driver side rear frame rail is rotted away. I got a replacement from a donor car in AZ and now have a question about next steps. As you can see in the picture, the rot begins at the yellow line and goes to the back. I have extra on the donor rail and feel like I want to use what I can. What do you recommend to create the strongest and cleanest replacement? In addition to butt welding with a sleeve (see pic), how would I best reinforce this? (I am just learning to weld; do you recommend that I hire someone?) Thanks! Terry

 

[icetech]

With the butt weld/sleeve you won't need to reinforce it, but i would take A LOT of measurements and make sure it's 100% in perfect position before you start, also if you are new a word of warning, the first few tacks you do will move the piece no matter how well you clamp it, tack it and double check it until it's solid and then fill the welds in. I would also coat the inside of the frame with corroseal and then rustoleum, but i'm crazy bout that..

Also while uyou have the old frame section cut out eastwood makes a internal frame sealant that would be easy to put in there.. Being from the rust belt and repairing a rusty car it's all i think about now
P.S. if you do the eastwood thing, tape the tubes to a straight but of coat hanger so it doesn't coil up as you push it in.

Eastwood Internal Frame Coating 14 oz Aerosol

Destroys rust hiding inside chassis so it won't rust through

www.eastwood.com

 

[#41]

This is not a hard job. Brace off the old rail and measure very carefully where you cut both pieces. Use marks on the brace to reposition the replacement piece in the same spot. Practice horizontal welding a bunch before you start and make sure you are getting full penetration.

 

[slimt]

I sure would not weld it solid till you have the other tin in place and make sure its lined up.

 

[mgoblue9798]

My driver side rear frame rail is rotted away. I got a replacement from a donor car in AZ and now have a question about next steps. As you can see in the picture, the rot begins at the yellow line and goes to the back. I have extra on the donor rail and feel like I want to use what I can. What do you recommend to create the strongest and cleanest replacement? In addition to butt welding with a sleeve (see pic), how would I best reinforce this? (I am just learning to weld; do you recommend that I hire someone?) Thanks! Terry

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After you have it braced, you need to cut out the rot first and see how far it goes. Only then will you know how much of the replacement rail you will need to get rid of all the rust.

Making a sleeve like the pic will offer some additional strength. Drill out all your spot welds and use clecos or sheet metal screws to hold things in place while you do your plug welds. Check your alignment often and especially early on when you have a few welds holding things in place.

Something extra I do to prevent further rust is to use a zinc rich weld through primer before welding, and/or spray some primer inside the rail with a cavity wand after welding.

 

[RM23U0A]

Since you are the one asking for advice, here goes; I am a retired welder; highest cert. o'' to unlimited thickness, pressure vessel. and as a Mopar restorer I see so many challenges in the pictures that you show that I am sure that you do not know where to start and are unskilled to perform safe roadworthy repairs. I urge you to befriend someone who does know how to; before starting reassembly! Remember that you are the one liable for the car going up and the highway and that there are plenty of lawyers just waiting for something to happen. Good luck, Wayne

 

[1STMP]

I'm in agreement with RM23UOA on this one.
It looks bad enough to me that full access
to the frame is required to set the frame in
its' original position. Pulling the body off at
a minimum. Welding access to all four
surfaces is imperative. Doing this will also
allow you to inspect and repair other
questionable areas. It would require a lot
of effort to remove the body, but at least
you'll know what's under you won't
jeopardize your life, or someone elses'.