Just got a 92 si off a kid yesterday for good price, heard clunking when hitting dips, thought it was blown rear shock like he said. Got home and the rear sway mount has torn out on the drivers side and is clunking against the frame. The tire shows HEAVY inside wear and is down to the belt, I'm assuming from lack of sway pressure don't know much about suspension.

Possible to cut out ripped section and weld a plate to the frame or is it too risky? How much stress is placed on that mount? Would the hole need to be perfectly placed to get allaignment in check>?

Thanks

Mike





BTW to those who say to search, don't really know how to explain what this incident is and need to fix it for daily driving.

 

well first off, your tire wear issue is most likely from a camber/toe mis-adjustment. that kind of tire wear would not be caused by a broken sway bar.

-get an alignment

to repair the broken mount i would cut out the frayed metal, then fabricate a "U" channel from some heavy gauge steel that goes up half way and wraps around the frame channels.

weld some large nuts to the inside of the fabricated piece so that they recess into where the old holes used to be.

fit the new piece so it fits where the sway bar mount used to be and make a complete seem weld around the fabricated piece to the frame.

re-mount the sway bar.

>>>>be sure to use a wire brush to get rid of ALL the undercoating, it will ignite and drip hott *** burning liquid rubber on you! not fun i learned this by experience.<<<<

 

this actually happened to my car as well. My mech simply welded the remainder of the bracket to the frame and its held up perfect.

 

There seems to be allot of material left on the frame and mount so you should be able to remount it and weld around the perimeter to have it hold very well. But remove the undercoating where you are going to weld so it doesn't catch fire.

 

Thanks for the replies, I would like to do it with the U joint like h23prelude suggested, but there is no room between the frame and the interior wheel panel.

Going to try to weld rest of piece back on, got it hammered/bent back pretty good, and hope it holds.
If not Ill plasma the section of panel that is in the way, cut out about 3/16in of frame and weld a 5/16 piece of U tubing all around.
Looks like he hit that back end HARD, the wheel itself has a weld on the inside part of rim...
Good thing I'm motivated for projects/fixing.

Thanks again.

 

Spent all day saturday fabbing up a piece of 4"L x 2"W plate steel on advice from one of our families friends who has been a mechanic for over 30 yrs and put together halves of cars.

Was skeptical but worked out ok. What also helps is to countersink a couple holes through plate to make "spot welds" to the remainder of the frame in center section. On the plate we made we had 4 of these spot welds.

Welded 2 nuts to the back of plate before welding plate to frame for bolt to screw into.

Tacked around the out side corners in torque like pattern, tack one corner then tack the opposite to allow for thermal expansion. After tacking one side, beat the whole plate with hammer to make it sit as flush as possible with frame, as well as shot peening the welds to some extent to remove stress.

I was doing this with 3/32in 7018 stick on DC - polarity at around 80-85amps which was on the hot side. Not having good fitup, as well as some coating remaining on the frame, recommend you use some acid to remove gunk from weld area, played hell with the arc.

As a result, the spot welds and the 4 corner tacks (When i refer to tacks, holding for a good 3 seconds to make a complete fusion) turned out good. The rest of the attempted welds went shitty. Hard to start arc, long arcing, excessive amperage and heat from long arcing melted through frame metal causing multiple gouged holes.

Regardless, the integrity is good and sprayed with rustoleom immediately after should ensure decent longevity and i know what to change if I ever do frame work again.

To anyone welding 3/16 steel to frame with 3/32 7018 rod I recommend the following procedures:

75-85amps DC negative (varies by machine, do a test plate in the position you will be welding in, when you do a bead and the back of weld plate has bubbled through with a clear heat line throughout the whole weld, that is you setting.)
Also that amperage was for overhead welding. For flat, horizontal, or vertical you should use less > 3-6amps

Instead of doing beads, spot weld sections in opposite torque patterns.

CLEAN THOROUGHLY! Prep is 90% of the finished product and it is especially true in welding. Wire brush as much as possible, use some degreaser and stripping compound (pb blaster/ brake cleaner?) and final with rubbing alcohol to remove flammable agents.

When spot welding, use drill bit to counter sink holes in plate so you get penatration into frame completely.

After each weld, hammer piece/weld to get it to conform as best possible to frame. The more flush it is, the less stress with have leverage to the tearing and cyclic stresses placed on the frame. Also, beating the weld removes stresses from it as the metal cools and contracts, slightly helping prevent the Martinsite crystal lattice structure from forming and making the weld area brittle.

DO NOT USE TOO MUCH HEAT! The hotter the weld gets, the more likely you are to have blow-through. More importantly, at 1333 F, the crystal structure of the steel changes and the hotter the affected area gets, the longer it takes to cool down and the more brittle the steel becomes. Run test beads and use the lowest setting that still provides adequate penetration.

DO NOT QUENCH THE STEEL! Allow the metal to cool down naturally by itself. Accelerated cooling makes the steel hard and brittle which is not what you want in a part that is subjected to constantly changing stresses.

When welding around the screw or nut area, have a bolt screwed into the nut but not hanging out depending on the side you are welding. This will prevent any spatter from damaging the thread of screw or nut and rendering all this work null and void.

We used a small self-tapping screw in one of the spot weld holes to hold the piece tight to frame while making first couple welds. After that take screw out and spot weld the hole it was drilled into.

That's all I can think of now. Was a great learning experience and know now how to make it quicker and more effective if need arises again.

Any ?'s let me know and I will try to answer.

Mike