Broken K-frame Fix
My 1984 300D right wheel started pointing 20 deg right with left wheel straight, while my son had it in San Diego. No photos that showed me the problem, so I had to take every tool I could think of. We were planning a Labor Day trip the next week anyway to swap the 1985 300D with him, but now drove our 2002 T&C van in case we had to tow-dolly it home (worst case). We tow-bar'ed the 1985 the 505 miles there (another post), saving fuel and easier for us, plus proved the method in case needed to recover the 1984.
I am sure most readers can imagine many things which could cause severe toe-out. Hint - when I bought the car years ago, the owner said the K-frame had "cracked again". First time was when it was stolen and crashed into a curb, then fixed by a shop. I found those weld repairs sound, but the left "LCA pocket" had cracked thru the hole, letting the LCA move outward, causing extreme camber & toe-out. After pulling back and tacking, I welded a metal strap across the bottom of the pocket. My son was sure the problem was that my weld had broken, but never sent photos of the left side, saying the problem was only on the right (makes sense?). 1st photo is my left LCA weld repair, still sound, though only 2nd time I had used my $90 Harbor Freight flux-wire welder.
I found the problem was on the right. The long-ago K-frame repair had separated (son swears he takes speed bumps lightly). The 2nd photo shows a large gap where it was welded to the spring tower, 3rd photo where it punched thru the bottom of the frame rail slightly. The car was in a parking garage. I strapped chains around the springs and used a come-along to pull the LCA back (as I did for prior right-side repair). I attached other chains (1300 lb rated, Ace Hardware) to the LCA's at their pivot and tightened (4th & 5th photo). The chain fit perfectly between the engine and K-frame, not touching the oil pan. I then adjust to 1/8" toe-in (used tape measure, required just slight tweak after pulling LCA tight) and drove 10 mi on I-5 to the motel, w/ just the chain holding the right LCA in position. The car drove like new, perfectly straight w/ hands off the wheel and steering wheel centered. Later, at the motel when I jacked the car by the frame, w/ wheels hanging, I found the chain loose so appears I didn't even need the come-along since the weight of the right wheel rotated the K-frame end into position.
We were going to tow-bar the 1984 home. Backup plan was to buy a tow-dolly (some for $400 on craigslist) or rent ($110 U-Haul). With a tow-bar, if something broke free the heavier van would still direct the car, so a bit safer. But, my wife wanted to attend a meeting in LA, so I ended up driving the 1984 home. No problems, or strange noises, and got 26 mpg even w/ crossing the mountains and stuck 2 hr in a jam (fatal accident in Lake Hughes). Many here wouldn't do that drive, and they should probably wear helmets while walking. I couldn't imagine the chains breaking.
At home, I made a permanent repair. I removed the turbo and engine mount, supported the car on the frame, then jacked the LCA pocket up tight against the K-frame and tacked in place, then removed the jack. The K-frame and LCA pocket is fairly thin sheet metal, not exactly the ruggedness people imagine of these cars (many also ask if I get 45 mpg, "no, that is VW diesels"). Previously I had fits trying to butt-weld a new floor (similar gage steel) in my 65 Dart, since kept getting burn-thrus. My HF welder has just min & max power settings. Max works well for 1/4" th steel, while min is a bit much for sheet metal. To try to reduce power further, I used a 100 ft, 16 awg AC extension cord (seemed to help). Welding was still tedious, w/ many passes of welding, wire-brushing, and grinding. I welded across some gaps by hammering re-bar tie wire into the gap.
To insure the top didn't pull away from the spring tower again, after solidly welding, I welded an L-brace over that (framing brace from Home Depot). Before covering bare sheet-metal you should protect both sides with "weld-thru primer". As others, I use the inexpensive "high zinc" primer shown. I also added a strap across the bottom to insure it couldn't punch thru the frame rail again. Probably over-kill, but don't want to revisit this repair. I would similarly improve the left side, but await a time when the hoses are out for other repairs. A tip, try to determine which side is thicker gage and start welding there, otherwise the new metal may stick to just the thinner side (appears what happened in the shop's job). In my case, the framing brace seemed thicker than the K-frame, and the lower strap seemed thinner than frame rail. Last photos (post 2) show the finished repair before paint.
Last edited by BillGrissom; 09-20-2014 at 07:23 PM.
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