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MG Midget and Sprite Technical - Why doesn't my suspension line up?
I'm replacing both wishbones and suspension bushes in my car. I did the lHS no problem but on the RHS the arm doesn't line up with the top trunnion by a long way. Looks like something is amiss. Nothing on the body looks out but I did notice the arms on the shocks are different and thought perhaps the arm on the RHS wasn't correct and sat further back. Anyone know if they are differnt in there offset or just a differnt looking arm? Or perhaps I've done something wrong? I can force it by loosening off the wishbones and removing the outer wishbone bushes and with a bit of effort force can get it to line up but this puts a lost of stress on the bushes and so I'm not happy with doing this. |
Greg H |
the difference between the LH and RH arms
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Greg H |
Greg I would say that there is a problem with the damper in the R/H picture, it looks to me that the arm is coming out of the main body of the damper. Ian |
I Pickering |
I'd say your LH damper is ruined and should be replaced. Is it possible that you switched the pan sides and the busted damper is associated with a twisted pan? |
Trevor Jessie |
I didn't notice anything wrong when I pulled it apart. The pans didn't have twists in them. I decided to replace them because the lower pin on the LH one was slogged. The RH pan actually looked fine but I replaced it anyway. I had to cut the king pins out so can't try it back in there. The LH side (right pic) is the side that fits ok yet you both reckon it has a problem. I take it there's not meant to be a gap between the arm and damper. Is it possible they are both ok but look different as the dampers are off a different model. |
Greg H |
sorry but l/h/s one isn't as it should be |
Nigel Atkins |
You guys really haven't helped at all on this one. I was after some advice on how to fix the RHS as that's the one with the problem and now both sides are stuffed. You're meant to be helping me fix it not break it. I shall investigate further tommorrow. I'll make sure I never put a photo of the whole car up on here. lol |
Greg H |
Greg since the BBS hasn't helped (YET) lets try a different tack can you slacken off the three shocker bolts on the "wrong" side (your wrong one, I've seen arms that far away from the body of the shockers before now. I don't think anyone died but they don't look good) With the shocker bolts loose try to move the body so the arm moves back to where it fits the kingpin, you may just have a slight alignment difficulty that will disappear when set up "proper like" then bolt the thing back down ever so tight, an' a bit! |
Bill1 |
Slackening the 3 bolts that hold the shocker in position should not have an affect. These bolts are designed to hold the shocker in exactly the right position and should have no movement in them unless you have used substandard fixing bolts which I assume you haven't. I have seen this on rebuilt and new shells when the shocker turret/base has not been welded correctly in position and will therefore hold the shocker in the wrong place to align the suspension, has any welding been done in this area? |
Bob Turbo Midget England |
Bob, It does have an effect, as Bill describes. Its not a lot, but with the length of the lever arm it may be just enough to make a difference. Slackening the shock mount bolts will allow a degree or two of movement at the end. One of the reasons I check mine are tight regularly! I also believe that even good condition lower wishbones take a "set" to the side they are fitted. If they inadvertently get swapped over this could explain the misalignment. But the "good side" shock doesn't look right does it! Mine are not like that. Maybe there were different batches made to slightly differing design and somewhere through its life it has acquired a mis-matched pair. |
Guy |
Well if it has that much affect Guy then something must be seriously wrong!! |
Bob Turbo Midget England |
Bob, If there wasn't some tolerance on the threads then I doubt that you would get all 3 shock mounting bolts through their holes in the shock body and into their respective threads without some difficulty. But I do agree, it shouldn't be enough to account for the misalignment in Greg's first photo which is rather more than "a degree or two"! Which is why I added the bit about wishbone pans. If ever removed, they shouldn't be swapped over |
Guy |
Whilst we agree that Greg's "good" damper doesn't look right at all, is there a chance that the problem on the "bad" damper side is not actually damper realted at all but more to do with how Greg has mounted the wishbone or possibly the kingpin? could you post a pic from below showing the wishbone mounts and from the side showing the lower fulcrum? |
Matt1275Bucks |
A number of years ago, I took a hit to my front offside tyre by another car, when I was turning right. It hit right in the middle of the tread. The shock arm was bent back towards the rear of the wheel arch, and the pan twisted. When I changed the shock and pan, I had exactly your situation but I can't remember if it was that much. I never worked out exactly what was bent. I just twisted the new pan a bit to accomodate the misalignment and bolted it up. It never caused me a problem with premature wear in the rubber bushes, and the bushes in the wishbone end seemed to wear at the same crap rate they always did too. Later when I fitted the FrontLine kit, the alignment was ok. So I assume it straightened itself out again in use. |
Lawrence Slater |
ok took a few more photos. 1. Slackened of mounting bolts but damper was very solid and had no noticeable slop. Put fwd pressure on it and retigtened. no change 2. Wishbones are new and haven't been on the road. 3. No welding has been done and all looks orginal 4. The damper housings are different and the LHS arm looks like it's sticking out further because the housing is shorter. I still think they are ok but one has been changed at some time. The back of the arm of the RHS (problem side) actually sits further forward and so should make it better. If there's nothing obvious I can force it on but I just don't like doing it to the bushes. |
Greg H |
the differences in dampers
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Greg H |
Greg did you take this car apart? and was it ok then? |
Robert (Bob) Midget Turbo |
Greg, Can you take the dampers off and put them back to back (base to base) to give a comparative indication of whether the damper arm or spindle is bent on one relative to the other. As far as I know they're mirror images so the arms should align with one another. Difficult to tell from the first pic but it does look a bit like the arm is more rearward than it should be. |
David Billington |
Yes I pulled the car apart. That was the easy part. It was good on the road. The car appears very orginal and straight. The the only change is new wishbones. Both wishbones were bought at the same time from same supplier and were identical. I didn't notice anything wrong when I pulled it apart but didn't pay that much attention to how it all lined up. I didn't notice the bushes to be unevenly worn either, just worn out. Another pic from above.
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Greg H |
David I suppose I could do that but I only just put the LHS back together :( It would certainly show whether that's the problem. Were there different types on different models or did they all look the same? |
Greg H |
Were the wishbones new or refurbished ones? Perhaps that isn't critical. But when they are refurbished new bushes are braised (or welded?) in, using a dummy fulcrum pin screwed into them to get them aligned. I guess only a small amount out when they are fitted would cause the kingpin to cant over out of alignment. One used to be able to buy just the bushes for DIY repair but I never had the confidence that I would get the alignment correct. I am sure it should be properly jigged, but maybe one of yours was faulty. It would be almost impossible to tell just by looking at it. |
Guy |
New wishbones
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Greg H |
Maybe just the way the light is reflecting but the one on the right looks like it could be a refurbished one. The bushes for the fulcrum pin would only need to be fitted in a little crooked to set the kingpin out of alignment at the top. |
Guy |
No not the light the one on the right is a knackered one out of the car. They were both as per the left one. A comparison showing that the new and orginals looks exactly the same. |
Greg H |
LoL I thought it looked a bit grubby for a new one, but didn't want to be rude about it! |
Guy |
Guy, I've heard of that technique of using pre-threaded bushes and a dummy fulcrum pin to align them but was told years ago that the correct way is to use plain bushes and a special stepped tap to make sure the threads are cut accurately after brazing and with the helix coincident. Maybe that tap is now rarer than the kingpin reamers. |
David Billington |
David, Beyond my abilities either way! Greg, It seems to me that as it all aligned before you dismantled it and the wishbone pan is the only component changed, then it rather points at that being the culprit. Maybe a manufacturing fault. Its clearly critical that the bushes are aligned correctly, however they are fitted. If this bit of the job was done wrong and not checked, then that could be your problem. Can you go back to the supplier? |
Guy |
Have you tried refitting the old wishbone pan to see if it aligns correctly? If so, that would confirm it is the wishbone that is out of kilter. |
Chris H (1970 Midget 1275) |
On holidays this week and so I thought about it today but that was about it. I decided to finish making all my new brake lines and also stripping my wooden steering wheel to see if I can restore it. i.e. finding excuses not to tackle it. :) I want to take both dampers out and compare them but it will require a bit of fiddling as the car is on jack stands and my only jack is holding the RH wishbone up from under the spring. As I don't have another jack I'll have to pack that side up first. If the dampers look the same then I'll either try the old wishbone back in but it's been a little hacked where the kingpin goes so don't know how that will work. I'd also hav eto get half a chopped pin out of it or I could put the new LHS one in the RHS, but that will require a bit of motivation for me to do that. I promise I'll tackle it tommorrow and report back. |
Greg H |
Greg, I seem to recall that people have put themselves through this before because the jack has been bearing unevenly on the underside of the wishbone causing it to twist and giving the misalignment you're experiencing. |
David Billington |
It was misaligned before I put the spring in there and there was no jack under it. It was free to move but didn't line up. When I wa sfitting it several weeks ago I loosened the wishbone pin bolts off to force it in. I decided this week to remove the damper to paint it. I put the jack under there to hold it all up when I removed it. Putting the damper back on I decided rather than just force it I'd see if I could fix it. I'll see what I can sus out tommorrow. |
Greg H |
Good point David, I hadn't noticed the springs in the original photoes. Greg remove the springs and then offer up the trunnion to the arm and see what difference there is then. Dave |
Dave Brown |
Dave that's how I fitted them. i.e. no springs in then put the springs in after. LHS no drama RHS not ok. |
Greg H |
Greg, for reference, here is how the shock arm should align with the shock body. The trunnion face should be exactly perpendicular to the cover plate on the shock body, and should align with the arm-side edge of the shock casting. Hope this helps. Peter
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Peter Caldwell |
What Peter says. Failing that, I'd be tempted to try another wishbone, but that's easy for me to say... |
Dave O'Neill2 |
squirrel or magpie? |
David Smith |
LOL |
Dave O'Neill2 |
I doubt the replacement 'bones are the issue. I suspect the chassis is tweaked. The right shock arm appears bent toward the rear of the car. The let side shock shows the arm "wants" to pull out of the shock... or forward on the car. Take a close look at the subframe. The left shock arm wont stay where it is for long. There is distressingly little to hold it into the shock. Peter C |
Peter Caldwell |
Looking at Greg's photos of the shocks, it looks as though the LHS projection on the trunnion is too short when compared to Peter C's photo. so probably the LHS trunnion is at fault and not the shock lever. Could be wrong but that's where I would be looking. |
Peter B |
Well I know where the problem is. It's the RH damper. Peter your pic made it easy for me and saved me a bit of work. My car was a little offended at your subtle suggestion its chassis was tweaked i.e. bent. Thanks guys for all your help identifying it. So the LHS one which some of you guys hated appears ok but the RHS angles back. Why so? The housing is different to the RHS so is it the wrong damper or just a bent or incorrect arm? Dave, WTF?? Perhaps a sign that the bodies don't last long there? Not many spare midget parts here. I'm lucky to see one on the road every few years. I've saved you a bit of postage as there's no need to send the wishbones now, but if you've got a spare RH damper laying around that'd be nice. No dodgey bent ones I've got enough of them. ;) |
Greg H |
I've probably got about 30 of each, so take your pick. |
Dave O'Neill2 |
I wonder, are there perhaps two styles of damper body and you have one of each. Then to go with the two body styles there would be two different lever arms to give the correct offset required. If your RHS unit has been refurbished and fitted with an arm of the other style of body then that might explain why it is wrong. Peter will know for certain. |
Guy |
Guy I thought something like that but it doesn't appear to be orginal as it's got an Aust patent on it. Although since it's so similar I wonder whether it was made under licence. The arm has Mowog on it but the two arms on my car are different so defintely a couple of different types of original arms. Dave thanks for the offer. I'll take the one that's 3rd to the right of the yellow one and two down. If that ones no good or the paints a bit average I'll have the one 2nd to the feft and five back. lol. Problem is there a bit heavy 3.3kg so postage to here would have to be by courier and courier deliveries start at about £60. A new one is only £50. I have to buy a bit of stuff for my car which will come from the UK and if I add one to the order the extra post may not be too much. If it's a problem I'll have to try and source one in Aus. |
Greg H |
Greg Down your end of Tassy is a guy called Craig Trenham He has quite a lot of sprite/midget stuff, I'm sure he would have one or know where there is one for you. Or Craig Twining in Launceston It looks like a bent arm in the pics. to me, as the arm appears parrallel to the housing at the shockie end but definatley twisted around out of square on the outer end. If you run a pair of straightedges along the machined sides of the inner and outer ends of the arm they should run parrallel to each other-- Hope this helps -- Willy |
William Revit |
Thanks Willy hopefully one of them will have one. If so it'll makes things a bit easier for me. Found a couple of possibles for them in the phone book Cremorne and Sth Launc? |
Greg H |
Greg and Guy. There is only 1 shock that looks like these. They can't be confused with any other. No other shock uses that arm. The arm and body is unique to Spridgets and some years of A35s and A40s. Typically, the slotted head screw ones are earlier production, and the cross-headed screw ones are later. I think you have one of each. Certainly one is bent. If it were due to a collision, then likely there was some collateral damage. If it was bent to enable installation previously, then certainly there's damage. Be safe, it's "only" suspension. Peter C |
Peter Caldwell |
Greg Twining's home no. is 63443128 He is also president of MGCC Tas Willy He will know where Trenham hides as well |
William Revit |
Willy, spoke to Craig's son, he's going to have a look for me. |
Greg H |
Willy, Craig Trenham had a pair for $20 which I got off him. The right one was stuffed but I thought I could use the arm off it until I took the nut off and found it had been welded onto the damper. I assume the spline was flogged out. Craig Twining gave me the name of another guy called Jim Hooper in Devonport who had one. All sorted. :) Thanks for your help. |
Greg H |
Hey Greg I live not far away from Jim-------- Didn't think of him initially, but as long as you are all sorted, that's Ok Cheers Willy Do you know the past owners of your car, it looks sort of familiar but just can't click on where or when----- |
William Revit |
I bought it in July 1993. It was sitting in a shed in Fern Tree where it had been for most of the 10 years before that. The previous owner was Alasdair Adams. Mostly complete but no interior trim, no hood and the head was off the engine. It had a hard top. The engine was already 0.060" over when I got it with high compression pistons so the owner may have been a bit of a lad. I suspect a problem with it is why it orginally came off the road. Back then I painted it, rebuilt the engine, interior. I only drove it for a few years in the mid 90's and it has sat since. So it's been off the road for most of the last 30 years. Perhaps another one you're thinking off. The little car certainly deserves some time on the road. |
Greg H |
Cheers Greg Can't be your car I'm thinking of then, I don't know Mr.Adams. Just interested me that it looked familiar Looks like it's coming up ok in your pics Willy |
William Revit |
This thread was discussed between 03/01/2012 and 18/01/2012
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