pinch bolt engineering

First off sorry for the non-technical names if they are confusing let me know. The metro is a 1996 1 liter 3 cylinder with 270000 miles. Alright I am asking for the knowledge of the World Wide Web on this one. It involves the pinch bolt behind the front tire that attaches the control arm to the tire. I replaced the driveshaft and control arms last april. Since I did that I had a slight steering annoyance going around corners. Well the other day I hit a big bump in town and the pinch bolt popped right off of the nub of the control arm creating mass mayhem, drive shaft came out and the tire looked like a wounded duck wing. After a quick fix in a snow storm I got the metro on a trailer and home. It is all a simple fix to put together except why that nub came out of the pinch bolt. The bolt I had in there was very worn you could see where the nub kept hitting it creating an area with no threads. So here is where I am scratching my head, is that nub held in there only by the threads of the bolt? I got a new bolt and tightened it as much as it would go and it does not pinch that nub securely. Is there a ridge that is supposed to catch that nub and mine is just worn off? I find it hard to believe that the threads of a bolt hold so much of the car together.

Can you identify the "nub" more clearly? Are you talking about the ball joint? I dont think you're talking about a tie rod because the axle wouldnt pop out if one of them gave way.

Yes the ball joint on the suspension arm. It is indented like a pawn on a chess board. that indention allows the bolt to slide through with thicker areas above and below the threads in the bolt. it is just hard for me to believe that is the only thing that keeps that ball joint in.

you probably didn't have the ball joint stud all the way up into the hole so the top of the ball joint was sitting on the through bolt instead of it going through the indented part of the stud. when ball joint stud is in the cosket far enough the rubber boot of it will be touching the part bolt goes through, its not uncommon to get have to tap the stud up the last 1/2" or so to get it up far enough

I cant say if i installed it right the first time or not. I can tell you where the bolt that comes in contact with the ball joint stud the threads where hammered flat. After installing it again i can move the suspension arm up and down just a bit allowing the ball joint stud to move a bit. the stud is flush with the top of the pinch bolt hardware with the bolt going threw the indentation. So i am guessing that if that bolt is the only thing holding that in, the small amount of play over time could hammer that bolt down and allow the stud to pop free?

if its in tight and correctly it shouldn't move at all

Well the loose ball joint stud has turned into two problems. I found one of the bolts on the control arm rear bracket was rusted out and would not tighten. This allowed me to move the control arm up and down which was causing the ball joint stud to bang on the pinch bolt. The second problem and just as worrying is with everything connected I can move my tire in and out about a quarter to half an inch creating extremely loose steering. The drive shaft and ball joint move. The tie rods are secure and I have checked the steering knuckle bolts and strut mounts everything was tight. The hub nut was also torqued down to 129. I am not sure how to correct this problem. Any ideas would be very helpful. the drive shaft is brand new and the control arm with ball joint was new in may.

http://img707.imageshack.us/img707/4223/driversidehalfshaft.jpg

I was wondering if this half inch is suppose to be there? I have about a half inch of movement in the shaft side to side when everything is connected. unfortunately i do not remember if this was there on the original half axle. I cant get it to go in any farther but it doesn't come out with firm pulling either. Is it possible they gave me the wrong axle? my metro is a 1.0L. I cant figure out any other reason why my wheel would move that much side to side.

Sounds like the excessive play in the ball joint either caused the snap ring on the trans end of the splined axle to come off in the differential or was it on there to begin with? Dunno if the lack of that snap ring could cause extreme force enough to work on the ball joint/control arm or if the ball joint was just installed incorrectly.Or both.

the snap ring might cause in and out play but if he can't pull it out its still on the axle. side to side play would indicate wrong axle or worn bearings inside the transaxle. it normal to have a little in out motion but not side to side and i would suspect your wheel bearings or a bad ball joint for hub movement

In my opinion if the axle was wrong it either wouldn't fit in or stay in. As many axles as I've done I always lay them side by side to compare critical dimensions. It only takes a minute. If the wheel hub bearings were that bad it would have either locked up by now or caused so much vibration and noise you teeth would chatter. The control arm bushings were probably so far gone that the thru bolt was bottoming out on the unthreaded portion of its shank resulting in extreme lateral movement. First you gotta address the control arm issue. You might have to replace it. Then inspect the steering knuckle for damage, replace the ball joint, remove the axle and inspect it for damage and if the snap ring is in place, get your fingers in there and inspect the splined side gear for damage, then check the side gears bearings for play or roughness. Then start back together with new parts. JMHO

i have replaced front wheel bearings on metro where there were no balls left on one of the bearings and it was still running down the road, no shake but nice rumble noise. also on the control arm you can take off the front nut and the 2 rear bolts to remove it and see what shape everything is in. do not need to remove the 2 larger center bolts. if you take the axle back off you can then spin the hub and see if the bearings make any noise or if there is any play in them

I re-threaded the rusted out bolt hole for the control arm and the new bolt can be tightened. the control arm with the ball joint was replaced in may and still looks to be in good condition. I attempted to pull the drivers side axle out of the trans axle but am unable to do so even with the assistance of a crowbar and plenty of frustration. i then took apart the passenger side to see what i could see. that side came out no problem like they have done in the past. looking through the other side i can see the axle there is the gear rod in between and the drivers side axle is touching this rod. now i think and may be wrong that the axle on the drivers side is too long. after popping the passenger side out the half inch gap that is currently on the divers side was apparent with more force i could snap the c clip all the way in and the cylinder would be touching the seal. I can not do that on the drivers side since it is already touching the gear rod. However i cant get the driver side out now so that C clip must be snapped into something. I still want to get that bugger off and take it in to a store and compare, just to see. Tomorrow i am going to replace the tire bearings seeing as the car has 270000 and i know i haven't done it in the last 110000. Thanks for all your help guys.

try turning the axle 1/2 turn and try popping it again, something you have to have the c clip facing just the right direction to pop it loose. if you keep doing that eventualy it will come out

alright so the wheel bearings where still in good shape. I still cant get the axle out so i went through and re read everything you guys wrote and made notes to check everything. My assumption that the control arm and ball joint where not the issue because they were new blinded me. the ball joint has excessive play in it and the boot around it feels like there is no grease in it. hope there was a warranty on this. I will let you guys know if this fixes my problem. Thanks again for all the help.

Most aftermarket ball joints come with a plug in the bottom that gets replaced with a zerk fitting,(grease fitting),that comes with it. If this wasn't installed and the ball joint greased it wont last very long.
I once had a Camry that I couldnt get the left axle out to save my life. I even had a neighbor freind of mine who was a Toyota line mechanic at a dealer come over with his tool and he couldnt get it either! We pulled the right axle and with a long thin rod knocked it out from the right side! It worked, but I had to change the seal on that side due to buggering it up some. The seal was easy to change. HTH

i have bought probably about 15 of the metro control arms from various sources and so far only one has come with a zerc fitting. on the other ones i used a needle fitting on grease gun, slipped it past the stud and filled boot with grease in case they didn't grease it at factory or was inadicuate ammount

i have bought probably about 15 of the metro control arms from various sources and so far only one has come with a zerc fitting. on the other ones i used a needle fitting on grease gun, slipped it past the stud and filled boot with grease in case they didn't grease it at factory or was inadicuate ammount
Nice try but that wont get grease circulated around the ball stud. Thats why they put the grease fittings at the bottom.

it will work its way past as ball joint moves around, don't really want to drill a hole in the bottom and take a chance on getting metal shavings inside it. most ball joints have grooves on side of ball to allow the grease to lube both sides of it, thats why when you use one with zirc the grease fills up the boot and comes out there if you overfill it. would rather add grease and add some from the top for extra lube than run it dry

Nice try but that wont get grease circulated around the ball stud. Thats why they put the grease fittings at the bottom.

Crvette69,

It seems none of us are ready to take you at your word lately. Don't let us drive you batty :runaround:. I can say personally I appreciate your input.

Alright so the ball joint was bad but it was not the complete fix. After everything was put back together the car drove like crap. I had my dad drive the car on our driveway while i watched the front wheel it would toe in greatly while driving forward but right itself when going in reverse. I need to get it aligned after this but something is still not right. So i took the wheel apart and got the bearings so i can see them again. the inner bearings look fine however they have a lot of play side to side between the outer bearings. The Chilton manual says there is a wheel bearing spacer? there isn't one left in mine. So i started calling all the part stores and they only sell one bearing for the front wheels and no wheel bearing spacer. is this because they have combined the two bearings? leaving no need for this spacer. I would hate to spend all this money to find out i still need more parts that i cant get.

i found the spacer Duh its attached to the hub. i am still confused on the bearings though. there are the encased bearings that have a little play in them and then the ball bearings. why wouldn't part stores and internet stores have both?

I went back to the first post to see that you have a 91 Metro, I assume that came with 12" wheels. In that case, you have two separate bearings with a spacer in between. You need a slide hammer to take the hub off and then a hydraulic press to press the new bearings in. Best thing is to take it to a machine shop and have them press in the bearings. If you have a 91 convertible, or any other Metro that came with 13" wheels, then your front wheel bearing is a single part # which consists of two rows of bearings. It's easier to remove and install, and also a bit more sturdy.

Alright Still in a world of hurt. When i tighten the axle nut onto the axle the wheel will no longer spin. it will move but with a lot of force using a crow bar. I tighten the nut to 129ft pounds. last week i had this same problem so i took everything apart and found that my inside oil seal was not seated all the way due to grease that had hardened over time. i chiseled this out and ordered a new seal since the spring in that one was ruined. that part came today put it all back together. everything works and spins like it is suppose to until that nut gets tightened down. Are there any ideas?

did you put the other spacer in between the 2 bearings before you pressed them into the hub?

And once you get the spacer sorted out, get another set of wheel bearings. Those ones that have been tightened down like that are probably no good now.

I am not sure about the spacer? This metro is a 96 and the bearings come as one unit. I took the entire assembly into a mechanic buddy and he said everything looked fine, same way he would do it. We got to looking at different axles and noticed the one i had on was for abs. i knocked that ring off and still does the same thing. I will describe what i do and post a picture later this afternoon. Alright the bearings come in a cylinder with two tracks in the middle i pound the cylinder into the Knuckle untill it is seated. I then install the C clip that keeps the cylinder in place. I install the outer oil seal. I then remove the outer track in the middle so the bearings in the knuckle can fit on the hub assembly i then hammer the inner track in the middle onto the hub assembly securing the knuckle to the hub, finally i install the inner oil seal. every thing works fine at this point. Am i missing a spacer somewhere in there? I did the other side the same way with no problems.

the bearings and the hub and the spindle should be pressed into place, not hammered. once bearing is pressed into place and you have used a bearing splitter to remove old inner race from the spindle then (making sure spindle spacer is in place and facing the right way, inner taper goes toward outside of car) you then press the spindle back into the hub using the center of the bearing to press against

Oh okay, a 96. That's a completely different deal and has a one piece twin bearing with no spacer. I don't remember needing to press it onto the spindle though, thought it just slipped on and then the axle nut held it on. I've heard of guys taking apart the brand new bearing to find little or no grease in there.

My bad, you do need to drive the hub and bearings back on with either a hammer or press. Here's a link to someone repacking a brand new bearing before installation:

http://geometroforum.com/topic/4294417/1/