Pinch bolt for knuckle/lower ball joint binds and strips on removal?

[W124_Karl]

Hi all,

I actually found some threads that looked kind of like this question, but not quite. And they were years old, so I thought I'd try a new one.

I'm rebuilding the front end of my new to me '89 with all made in the USA Moog stuff. The car came with updated knuckles for the 96 brake conversion. The problem I'm hitting is, when I remove the pinch bolt that clamps the knuckle to the ball joint on the end of each lower control arm, the bolt binds up. It's so bound up that removing it tore the threads right off of it the first time.

Now that I'm putting the car back together, it's the same problem. With the ball joint completely inserted, I can't simply slide the new pinch bolt in. In fact, I can't even hammer it through...instead, I had to turn it, as if threading it into the knuckle itself. And that had such resistance that it's tearing up the threads again, so I stopped.

I've never seen a pinch bolt do anything like this. Only thing I can think to do is drill the holes in the knuckle ever so slightly to get some more clearance.

Anyone ever seen this before? Maybe the previous owner overtightened it so badly that the knuckle is bent?

 

[rubydist]

I have had to put a screwdriver in the pinch area to pry it open so the bolt will go in. A large screwdriver or a small chisel should do it for you.

 

[W124_Karl]

I have had to put a screwdriver in the pinch area to pry it open so the bolt will go in. A large screwdriver or a small chisel should do it for you.

Thanks, rubydist. I haven't been able to go back out to the garage to try again, but I'll give it a shot. It seemed really odd to me that the presence of the ball joint shank would reposition the eyelets enough to make it hard to get that bolt through. Nice to hear that I'm not the only one to have seen this. Thanks again.

As an aside, getting the new lower control arm into place on the subframe side was a real chore as well. I finally managed to get that bolt through, but it really put up a fight. I have to imagine the suspension on these cars is really sensitive to bushing wear, because having stuff even slightly out of position can really introduce a lot of bind.

I'll get back to it tomorrow. Can't finish the job either way though. Not sure how, but I ended up with the wrong passenger side half shaft. Really looking forward to having it back together with an all new suspension.

 

[pjtoledo]

lets do a quick review on the lower ball joint and bolt.

being in the rust belt, its usually required to use a large punch to pound the old bolt out. never had one so stuck that it wouldn't come out after a couple of whacks.

then I put the tapered end of the lug wrench in between the stud and the CV, spray some **** while you work the stud a bit. they usually loosen right up.

the stud is "all the way in" when the indent on the stud lines up with the bolt holes. don't push it in too far. I use a tapered punch to align it.
the bolt is not supposed to be turned. the knurl under the head should be pushed into the hole, then hold the bolt and tighten using the nut.
chances are the hole is stripped where the knurl goes, so yeah its probably going to turn.
the holes like to fill with rust making it difficult to align the bolt. clean using something hard enough to chip out the rust without gouging the good metal.
test fit the bolt before the stud is inserted, clean and dress the hole as needed.

when installing the lower ball joint stud into the knuckle I use a piece of heavy pipe about 4 feet long. goes over the top of the tension rod and under the frame. then carefully keeping my feet under me I sit on the pipe to lower the control arm. use a big set of pliers to align the stud with the hole. you can also use an open end wrench.

 

[rubydist]

^^ all of that is correct, but sometimes the clamp will have the holes tight enough that it will not allow the bolt to go in unless you spread the clamp a little like I described in my earlier post.

 

[W124_Karl]

In the spirit of giving something back, I discovered something about these Moog lower control arms I bought. They're nice, seem to be of the appropriate thickness to be SHO specific, and made in the USA. They also have ball joint boots that are impossible to get seated. Turns out a spacer for 2" PVC piping plus a bench vise is just the right thing to get the boot on.

Anyway, back to the responses. Thanks for them, BTW, this is very helpful. This car goes together somewhat differently than the other stuff I've worked on over the years.

lets do a quick review on the lower ball joint and bolt.

being in the rust belt, its usually required to use a large punch to pound the old bolt out. never had one so stuck that it wouldn't come out after a couple of whacks.

then I put the tapered end of the lug wrench in between the stud and the CV, spray some **** while you work the stud a bit. they usually loosen right up.

the stud is "all the way in" when the indent on the stud lines up with the bolt holes. don't push it in too far.

Wow - now that's not something I ever would have guessed. Thanks so much! As soon as wife and kid are off doing their thing this morning, I'll be out into the garage to check on this. Here's hoping I can get the ball joint stud to back out some.

 

[W124_Karl]

Solved! Thanks to you guys. The ball joint stud wasn't in the knuckle quite far enough, it turns out, and it was the upper part of the stud that was interfering with getting that bolt through. The reason? Paint. Those knuckles had been painted black, and the paint was in the pinch bolt hole as well.

I also, stupidly, had the two bushing halves for the tension rods at the subframe backwards, explaining why it was such an ordeal getting the LCA bolted in.

Next project will be to order the correct halfshafts. BOTH of the ones I got from Rock Auto had the wrong spline count on the transmission (or int. shaft) end. I'll be getting this pair from shosource. More expensive, but they should also be a lot higher quality. And, you know, fit the car.