I'm going to send 3 parts of a torsion setting article I wrote years ago. Enjoy!
From: Glen Hadley <[EMAIL PROTECTED]> To: [EMAIL PROTECTED] <[EMAIL PROTECTED]> Subject: Re: Turning your Own Torsion Bars Date: Monday, June 08, 1998 6:23 AM And here's the torsion bars: Erin Lassley wrote: > > I wrote this up on word pad and pasted it into the mailer. I've tried to > proof read it and catch spelling errors but I haven't actually ran it on a > spell checker. > ---------------------------------------------------------------------------- > --------------------------------------------------------------- > > Adjusting the torsions on a VW with an IRS style rear end is not hard but > it does require a clear head and proper safety in order to do the job with > the least amount of risk. You are dealing with torsion springs that are > under enough tension to break bones should the spring and its attatched > hardware come un-sprung. > Please keep in mind that I am a VW amateur. I've never been factory > trained and my experience comes totally from reading VW repair manuals and > tips from other VW enthusiasts. I also figure a bunch of stuff out on my > own. Read this post for pleasure but if you decide to follow it for real, > it's your risk. > > When I refer to using a hydraulic jack, I don't mean bottle jack - I mean > a > regular car jack with a nice wide flat jacking base and on wheels. Very > important. > > The vehicle used here was a 1974 Super Beetle. > > The first step in adjusting your rear torsion bars (torsions for short) is > to get your VW up on jack stands. Since you are going to be working in > the > area immediately in front of the rear wheels, you will want to locate a > position for your jack stand that won't interfere with your jack. I had > this problem and had to reposition my stands. I placed both stands on the > torsion housing itself near the center of the VW. > > After removing the rear tires, squat down and look at what you've got in > front of you. There is your brake drum (the thing the wheel bolts to), a > shock (vertical plunger looking thingy), behind the drum is your brake > line, CV joint, and drive shaft. Now look up under your fender and trace > it down towards the front of the bug (FIF). You should see a metal tube > looking thing poking out with a trapezoid shaped cover plate surrounded by > (-A-) 4 bolts - there are 2 on top and 2 on bottom. The torsion bar > actually runs into this metal tube thing that sticks out. If you look > between this metal tube thingy and the brake drum, there is a metal plate > with (-B-) 3 bolts in it. > > Now that I have familiarized you with the area under your rear fender, you > are ready to tackle the project. > > First, remove the upper and lower shock bolts and completely remove the > shock. At this point, it's only in the way. Behind the brake drum, there > should be a rubber cone shaped thingy (looks a lot like the Coneheads from > Saturday Night Live). If you grip it firmly and wobble it around and > around, it'll wobble right off of it's mounting point. Yours might not be > there however - I've seen them completely rotted off and in same cases, > the > mounting point was rusted clear off. :-( > > Get your hydraulic jack and position it directly underneath the lower > mount > where your shock was fastened too. Raise the jack until it just touches > the mount and then just about a 1/16 of an inch more. > Before you go any further, get yourself an awl or some kind of scribing > utensil. Remember where those 3 bolts are at? (See -B- above.) Those 3 > bolts hold together 2 flat pieces of metal. You will need to mark where > these 2 overlap because when you reassemble everything, you will need to > get it lined up right so your alignment will be right (assuming it was > right before.) > > At this point, I was able to use my impact wrench and just blast these > nuts and bolts off. It also helped that I had Mr.VW help me do this > procedure 8 months earlier so all the hardware had been replaced with new. > I *STRONGLY* suggest that if your 3 nuts and bolts are rusted on bad, to > twist them off and then replace them with new hardware. You may very well > have to redo this procedure and dealing with new hardware is an absolute > pleasure. > > After you remove these 3 nuts and bolts, your brake drum assembly will be > free to move up and down. I was able to pivot the whole assembly all the > way up until the lower rubber stop mount was touching the upper rubber > stop > mount. I ran my bailing wire through the upper shock tower bolt hole, > down, and under the lower rubber stopper mount. The higher you get his > drum assembly up, the easier it will make the rest of the procedure. I > used a combination of jacking and dead lifting to get this rear assembly > up > "all the way." > > The next steps are where you need to really pay attention to what you are > doing. The procedure is simple so don't be scared to try it - just keep > your hands away from the area directly under the spring plate. > > Using my impact wrench, I was able to get 3 of the 4 bolts off (-A-) of > the trapezoid shaped cover that goes over that long metal tube thingy at > the bottom of the fender. These will be a PITA to get off without an > impact wrench. Believe me, it would be well worth it to get an impact > wobbly socket in the size of these bolts (I don't know sizes - sorry - I > just find my sockets by looking at them) and have a buddy blast them off > if > they are rusted in. Liberal amounts of penetrant will surely help. Just > don't twist them off in the holes or you will be in for a bad time. > > I didn't actually remove all my bolts one at a time. I broke each one > loose with a small bump from the impact wrench, and then I clamped a > c-clamp on the spring plate to keep it from sliding off its stop. I > removed all 4 bolts and the cover came off. Underneath that, is a ring > shaped piece of rubber - much like a doughnut. > Make sure you have a good set of gloves on your hands and carefully > (without getting your hand below the spring plate), remove the c-clamp. > Get your hydraulic jack and position it under the part of the spring plate > where the 3 bolt holes are. Since my torsions were weak, I was able to > jack up enough on the spring plate to just get it off of the stop (about > 1/16 of an inch) and then pull back on the jack (prying with a spoon bill > prybar) and working the plate off and over past the stop. I used the > prybar to work the plate past the stop and then at the same time, lowered > the jack s-l-o-w-l-y. You will be hitting on your trailing arm plate a > little bit but not enough to worry about. For cases where the spring > plate > has previously been installed too tight, you will need to get a bolt and > bolt a chain to the upper shock mount or any other holes in the shock > mount > area and the attatch the other end of the chain to your jack so the car > won't push up off your jack. I used a chain with a loop on one end and > hook on the other. The loop went over the bolt and then I picked up the > jack about an inch and wrapped the chain around the jack . You want the > chain good and tight when you start as any slack will waste jack travel. > This is why I would start with the jack hanging a little bit off of the > floor - there was enough tension during jacking that my chain or bolt > must > have stretched enough to let the jack touch the floor because it sure was! > > Once you get the spring plate off the stop, and lowered slowly with the > jack, take a hammer and tap around on it a little bit to make sure you > have > indeed released the tension. Once this is confirmed, you should be able > to > wiggle the spring plate up, down, and maybe in and out a little bit. > > At this point, I took my awl and struck a good scratch mark, even with the > top of the spring plate, on the hunk of metal behind the spring > plate(-C-). > I took good measurements the first time I did this and it wasn't good > enough. There is nothing like a visual reference for a guide during this > procedure. You will want to hold the spring plate up so that it isn't > sagging in its hole where the rubber doughnuts are. Keep it centered and > you'll have good accurate visual references. > > Now back to that metal tube thingy. I wasn't able to remove my torsion > cover or rubber doughnut completely off of the metal tube. (well okay, on > one side I could but that was because of the rust) Just slide them back > enough to get them out of your way. Firmly grabbing the end of the spring > plate and the end of the torsion tube, you should be able to wiggle and > jiggle and expose the orange rod inside the torsion housing. Don't get > too > carried away though. Pay attention to how things look (the orientation of > the spring plate) so that if you get all bawled up with the adjustment, > you > can put it back the way it was and start over. As soon as you can, get a > marker and mark a good black line in parallel to the torsion bar right on > the top dead center of the torsion bar. The change in the position of the > torsion is noticable on even 1 turn of the splines so this will be another > reference for you in case you lose track of where you started at. If in > the event the torsion assembly pops out and you lose your point of > reference, you can look at the little "tabs" or raised areas on the rubber > doughnut that runs between the body and the spring plate (the rubber > doughnut directly encircling the torsions.) Align the little tab with its > slot in the body and that should represent the initial setting your > torsions were at. For reference, we'll call this the inner doughnut. > > I must mention that on one side of my VW, the inner spline came out and > the > other side the outer spline came out. I used a vice-grip on the torsion > bar and then using my spoon bill pry bar, seperated the "stuck" end so > that > I had a free floating torsion bar. Vice-grips may not be the tool of > choice though. It mars up the paint on the torsion bar and can cause rust > and eventual breakage. Wrapping a rag around the bar and then gripping it > would probably work better or using a pair of padded-jaw tools. It's a > risk that I have assumed. > > Now the torsion bars have splines on either end. There are more splines > on > the outer shaft than the inner. I think there are 40 inner and 44 outer. > This allows you to fine tune the tension on your torsion bar. How so? > Well keep in mind that a change of 3/4" to 1" using your awl mark you > made > in the resting position of the torsion (this is about one turn of the > inner > spline) made a major difference in my 74 Super. This 3/4" to 1" is a > measurement taken at the rearmost gap formed by my awl marks on the metal > behind the spring plate(-C-). It made the difference of riding as high as > the suspension would go, or riding too low on the rubber stops. To get the > suspension just right, I had to adjust my "at rest" position of the spring > plate only 1/8 to 1/4 of an inch tighter. > > You may be wondering what I mean by "turning one spline." The end of each > torsion bar has splines or grooves cut into it which fit into a > corresponding grooves or splines. When you "turn one spline", you are > pulling the shaft out of it's splined hole, rotating it slightly while > attempting to stick it back in it's hole. When the splines line up again, > the shaft sinks in the hole, and you have just turned it "one spline." > It's like how you hold your hands when you pray. Your fingers are all > interlocked but you can pull your hands apart, and put each finger in the > next space (groove) over and although it feels weird, you've in essence, > turned one spline. > > So how are you able to adjust your "at rest" position in fractions of an > inch when the turning of one inner spline moves almost a whole inch? It's > much like being given a number, say, 5. You have to come up with the > number 10 by only adding or subtracting with the numbers 3 and 7. Well > you > can't just add 7 to 5 nor can you just add 3 to 5 - neither one gives you > the correct result. You can however, add 7 to 5 twice (19) and then > subtract 3 a total of three times. This would give you 10. So it is with > the torsions. You can rotate the inner spline one way (adding), and then > the outer splines back (subtracting) the opposite way and eventually you > will have come up with a setting that is mildly tighter than before - all > by adding and subtracting (splines) until you get the result you are > looking for. > > The more you adjust your spring plate (in its "at rest" position) > downward, > the more jacking force it's gonna take to compress it back up and onto its > stop. You will want to adjust for weak torsions by going down while in > the > at rest position, and adjust for too strong (too high) of torsions by > going > up in the at rest position. In short, the farther you have to move the > spring plate to get it back up on it's stop, the tighter the torsion and > the higher the rear end will set. > > After I set my torsions where I wanted them, I struck a line on that hunk > of metal behind the spring plate. This was in the at rest position. This > way if I went too far, I would have a reference point where my suspension > was at first, and then where it was now. I could estimate what further > adjustments I would have to make based up on the ratio between the at rest > position of the spring plate and the finished ride height of the car. > > Now you're ready to put it back together. You'll notice that your inner > doughnut has a couple of "tabs" that fit into a couple of slots in the > body > right around the torsion tube (mentioned earlier). I was able to spin it > by hand to get it to line up with the slots. If you do any turning of the > torsions at all, then you will have to rotate this inner doughnut. Mr.VW > and I had to use channel locks to move them initially. It can tear up the > doughnut a little but if you are careful, a few scuff marks won't matter. > Avoid massive damage. > > Once you get the assembly (spring plate, 2 doughnuts, torsion bar, and > trapezoid shaped cap) all kind of pressed back into their relative > positions, you'll want to use some longer bolts for the trapezoid cover. > This will help you draw up the cap tight around the torsions. It's just > too hard to get it all compressed into position without the aid of these > longer bolts. I actually ran a tap through these holes to clean them out > so that the new hardware would go in easier. It was slow - having to use > a > little 8mm wrench to turn the square end of the tap, but it did help. You > will only be able to get the 2 top bolts started and the one front bottom > bolt. The spring plate will be in the way of the lower rear hole. Snug > up > the 3 bolts (not as tight as you can go but get them firm and snug . You > want enough pressure on the torsion cap to press the spring plate into > position when you jack it up but not enough to warp the cap. > > Next, using your hydraulic jack, position it under the spring plate. Bolt > a chain to the upper shock tower mount and run it down as straight as > possible and anchor it to your jack. Watch out for your brake lines - I > was able to avoid mine. I had to actually raise the jack up a ways so > that > I could wrap the chain around underneath the moving arm of the jack. Make > sure you get all the slack out of the chain so that you don't waste > movement of the jack. I actually let the chain hold my jack a 1/2 to an > inch off the floor out at the front wheels so that when I started raising > the spring plate, I knew I would have maximum travel. It sucks running > out > of travel when the spring plate is almost into position - it just will not > go on until you are completely up and a hair past the stop. > > I now started jacking up on the spring plate. The tension on the chain > was > pretty darn tight. The first time I did this, I had a little slack in the > chain and it allowed the bug to actually come off the jackstand. It's a > very dischanting sound to hear the sound of creaking jackstands and metal > noises when you are doing this so down the jack went and I snugged the > chain up as previously mentioned. That took care of the problem. > > Once you get the spring plate jacked up so high, it will want to hit on > the > plate that extends forward from the diagonal swing arm. I took a hammer > and whacked on the springplate a couple times so that it would slide in > behind the swing arm plate (the one with 3 holes in it.) Once I got the > spring plate up high enough, it kind of wanted to slide back over onto its > stop but not quite enough I took my breaker bar and installed the the 4th > bolt on the torsion cap (the one you had to leave out previously). Use > gloves and don't get your hand underneath that spring plate in case for > some reason it pops down out of place. Tighten up all 4 bolts to spec > (I'm > not sure on the spec.at the moment) Now when you lower the spring arm, > push in on the jack so that it forces the plate over onto it's stop. Use > your spoon bill pry bar if you can to help gain little leverage and to > coax > it over. A few strategically placed hammer blows will help you as well. > Once you are on the stop, (make sure you really are completely on the stop > and not half hanging on!), you can lower the jack all the way down and > remove the chain. Take your jack and immediately position it under the > lower shock mount and cut your bailing wire off that holds the swing arm > up. You can lower this arm into position (it may need to be coaxed back > over the spring plate - a few good yanks here and there will guide it to > where you need it) and get your 3 nuts and bolts installed. You can use > the old ones if you have to but I suggest using new. Chances are that you > may have to do this all over again so it'll make disassembly easier. When > joining the trailing arm to the spring plate, you will want to make sure > you align both pieces using your awl marks you made previously. I just > barely snugged them up, moved the trailing arm into position with hammer > taps, and then snugged the bolts back up. Use lockwashers for safety's > sake. > > All you need to do now is reinstall your shock and your rear tire. Once > you get both sides done, you can check for whether or not you are sitting > level and adjust accordingly. Lower the vehicle and roll it back and > forth > to let the suspension settle into place. I measured from the ground to > the > fender lip. Previously I mentioned that I took good measurements in the > at rest position on the spring plate. I was off by about a 16th of an > inch > and that's all it took to be able to see the car lean when I was done. I > was dumb to assume it wouldn't have been anything different. So taking > meticulous measurements of your own could help you match the other side. > It also will help if you remember how many splines you rotated, inner and > outer, and which direction each side was rotated. Assuming your vehicle > sat level before, the same amount of turns on each torsion should keep > things nice and even. I didn't have the benefit of having identical > turned > torsions previously so I had to do a lot of guess work and ratio figuring > to get the desired results because I failed to remember how many splines > had been turned and on what side. > > I think that about sums up the process. > > You all have permission to put this up in your tech sections on your > pages. > Please let me know if you want to modify anything in the article. > Chances > are that something should be changed or added to, and I'm fully in > agreement with this. > > Email: [EMAIL PROTECTED] _______________________________________________ vintagvw site list vintagvw@lists.sjsu.edu http://lists.sjsu.edu/mailman/listinfo/vintagvw
