Adj LCA separated (!!!)

Carl McFly · Unread post by **Carl McFly** » Wed Nov 23, 2011 7:13 pm

Not sure what to say about this. Noticed something not quite right on my Heep and found this....

that's my passengers adjustable LCA. I'll need to remove it and do a closer inspection but somehow, the threaded end pulled right out of the LCA shaft

but wow how can that happen?!? It was threaded in for a couple inches or more, you can see where the lock nut is. The short end has threads, I can see and feel them and the LCA seems to have intact threads on the inside but I'd expect one side to be almost smooth if it was torn out like that. Guess I'll know more when I remove the arm and take a closer look. Looks like a new set of adjustable LCA's is on my priority list

nostaw · Unread post by **nostaw** » Wed Nov 23, 2011 7:53 pm

Check to see if the tube stretched out and the threaded end just pulled out... Seems unlikely, but...

JW

ChrisD · Unread post by **ChrisD** » Wed Nov 23, 2011 8:02 pm

My question is... If they were threaded together by a couple of inches, how in the world a fixed length pull apart 2"? Think about it, just weird. You could always remove some of the tube and weld a nut to the end.

Carl McFly · Unread post by **Carl McFly** » Wed Nov 23, 2011 9:39 pm

Little Napoleon wrote:My question is... If they were threaded together by a couple of inches, how in the world a fixed length pull apart 2"? Think about it, just weird.

yup........ that's been bugging all evening.....

when I pull the arm out I'll take a look. There's gotta be something else

Kurt · Unread post by **Kurt** » Wed Nov 23, 2011 10:28 pm

I believe I can explain it

I'd say the lock nut loosened up a while ago and was no longer asserting pressure against the end of the tube.
As a result the threaded rod and the tube can work back and forth just a hair since the lock nut is no longer doing it's job.
Over time this constant back and forth tiny movement eventually wears the threads away on which ever piece is made of the softer steel. The more it wears the more movement thus accelerating the wear rate.
When the threads in the softer (tube) finally chafe away the rod eventually yanks out.

Other possibility is you just wheel the poop out of your rig

ZAEDOCK · Unread post by **ZAEDOCK** » Wed Nov 23, 2011 10:53 pm

Kurt wrote:I'd say the lock nut loosened up a while ago and was no longer asserting pressure against the end of the tube.
As a result the threaded rod and the tube can work back and forth just a hair since the lock nut is no longer doing it's job.
Over time this constant back and forth tiny movement eventually wears the threads away on which ever piece is made of the softer steel. The more it wears the more movement thus accelerating the wear rate.
When the threads in the softer (tube) finally chafe away the rod eventually yanks out.

X2

Kurt wrote:Other possibility is you just wheel the poop out of your rig

Looking at the pics, the threads don't seem all that sharp to me. If it were mine, I would drill a hole on each side of the arm, reinsert the joint, butt weld the joint, and perimeter weld the jam nut to the joint AND arm tube.

Carl McFly · Unread post by **Carl McFly** » Wed Nov 23, 2011 11:14 pm

ZAEDOCK wrote:
Kurt wrote:I'd say the lock nut loosened up a while ago and was no longer asserting pressure against the end of the tube.
As a result the threaded rod and the tube can work back and forth just a hair since the lock nut is no longer doing it's job.
Over time this constant back and forth tiny movement eventually wears the threads away on which ever piece is made of the softer steel. The more it wears the more movement thus accelerating the wear rate.
When the threads in the softer (tube) finally chafe away the rod eventually yanks out.
X2

Looking at the pics, the threads don't seem all that sharp to me. If it were mine, I would drill a hole on each side of the arm, reinsert the joint, butt weld the joint, and perimeter weld the jam nut to the joint AND arm tube.

Thanks guys! Guess I'll be tightening my jam nuts. And Joe I'm definitely trying the cut and weld. Beats dropping $300 on a set of new arms

Thanks again!!!

Kurt · Unread post by **Kurt** » Thu Nov 24, 2011 7:42 am

ZAEDOCK wrote:Looking at the pics, the threads don't seem all that sharp to me. If it were mine, I would drill a hole on each side of the arm, reinsert the joint, butt weld the joint, and perimeter weld the jam nut to the joint AND arm tube.

That would do the trick

Carl - Feel free to stop by most any day to weld that puppy up.

ChrisD · Unread post by **ChrisD** » Thu Nov 24, 2011 8:49 am

What brand is this?

Carl McFly · Unread post by **Carl McFly** » Thu Nov 24, 2011 10:37 am

Kurt - PM sent. And thank you! I was thinking I may need a ratchet strap to align the axle, and a level surface to work and straps are easy to get but a level surface.... not on my street

Chris - They're Currie's. Like 90% of the stuff I buy, I picked these up two years ago, used. Bought a full set of eight, only the rear CA's were used

ChrisD · Unread post by **ChrisD** » Thu Nov 24, 2011 11:50 am

So it adds up how the threads worn out, however it still does not add up is how it "separated". you had stated that there was a min of 2" of the thread inserted into the tube. That would mean that the axle would have to twist on a angle at least 2". Since you still had 3 control arms attached, the axle shouldn't of had that much off axis rotation. The distance from eye to eye is fixed.

Just a note.. When you weld the jam nut, you are going to need another jam nut to take it's place.

nostaw · Unread post by **nostaw** » Thu Nov 24, 2011 3:15 pm

Seems like adding a bit of lock-tite to the jam nuts after getting everything re-aligned would be the way to go.... Welding it just means you lose the ease of adjustment the jam nuts are supposed to allow.

JW

Kurt · Unread post by **Kurt** » Thu Nov 24, 2011 3:26 pm

If I understand the problem correctly the threads in the tube portion are stripped out so I dont' think he can just re-assemble it.
It would just slip right back out again once it see's a bit of tension.
Just my guess without actually seeing it.

nostaw · Unread post by **nostaw** » Thu Nov 24, 2011 8:02 pm

Kurt wrote:If I understand the problem correctly the threads in the tube portion are stripped out so I dont' think he can just re-assemble it.
It would just slip right back out again once it see's a bit of tension.
Just my guess without actually seeing it.

If the threads are out, yes... Can't tell for sure, but I thought the threads in the tube were intact in the pic.

JW

ZAEDOCK · Unread post by **ZAEDOCK** » Thu Nov 24, 2011 9:52 pm

Little Napoleon wrote:Just a note.. When you weld the jam nut, you are going to need another jam nut to take it's place.

Not if you drill the tube on each side and butt weld the threaded shank. I would then weld the jam nut to the tube and then add a couple of puddles at the jam nut and threaded shank. Weld it that way and it would be mint.
Technically, you could probably do away with the jam nut, but the jam nut is probably a higher grade steel and the stronger threads would give me piece of mind.

Regarding adjustability - well, I don't think Carl is going nuts with additional lift, so insert the joint in the tube back to the jam nut (measure and compare to the driver's control arm to be sure) and then zap away.

Carl - I would spin some wire on the other side control arm too.

Baystate Jeepers

Baystate Jeepers