Lancia Beta Forum
Technical stuff => Suspension => Topic started by: JohnFol on August 22, 2023, 11:38:10 AM
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Morning all, over last few months I've had all the suspension bushes replaced and had new rear shocks fitted (by Lancia garages I hasten to add). I noticed the back of the car "wanders" even at slow speed, and I get tyre screech at very low speeds on roundabouts. Gut feeling is it's geometry so just had 4-wheel alignment done and it's clear the rear was out. That said, driving home and the issues are worse, i.e. tyre screech on straight at 20mph, car cannot hold a straight line.
Garage claim they cannot set camber as their computerised system doesn't have the specification. Even if I could supply it, they cannot set the values as it's all computerised.
Not sure where to go from here so any ideas, or garage recommendation near Reading who can diagnose suspension issues most appreciated
Car is '79 spider
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I'm reliably informed by the lovely chaps at Beenham Auto it's the beam. My guess is they will be hard to come by and probably as fragile.
Does anyone know of a source before I go the RSJ route?
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I’m confused with some of this. Claiming its ‘the beam’?
What does that mean? The rear cross-member? If so they are not very stiff pieces from the factory but they don’t really need to be. But what is supposed to be wrong with yours to be causing such severe problems as screeching tyres at low speed. Is it snapped?
Even if it was a little bent, with the measurements you have it’s not going to cause screeching at low speed.
Cheers
Ian
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Thanks Ian, intend to agree if all 4 corners are pointing all the same way, then where is the real issue. They fitted the rear dampers and commented the "beam" had some movement so today's comment is based on previous visit rather than inspection. So to be fair to them, it's the best guess until I can get it booked in
As for "beam", it's the bit all the suspension bits are bolted to so yes, cross member is a name I'm more familiar with.
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Hi John
Looking at your figures, it implies toe in at the front and toe out at the rear, pretty sure that the Haynes setting is toe out at the front and toe in at the rear? This is what I normally set the car to and never had an issue.
I do not know the value in minutes, just the value in mm based on 14 inch wheels, so cannot comment on the actual values. I could of course work it out….. will look to do so.
Anyone else care to correct me?
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Also just noticed you seem to have (if I am reading this correct) the camber changing between the two before and after which given you have no real adjustment on is interesting and implies all wheels are at negative camber?
As with previous comment, not sure what on the rear cross member can be affecting it as essentially just two bolt holes?
One thing to check is if any of those rear suspension arms are bent which is not uncommon.
Peter
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Hi John
The Beam description has me puzzled. Perhaps they mean the Rear anti-roll bar which on late Spiders can be moved in its U clamps affecting rear camber and set back (wheel base). I would look hard at all bushes and look for bent items as part of your strategy. Front wishbones bend far too easily as do the rear long links often thanks to poor jack use.
I fitted 4 adjustable rear links on mine to give more control over camber and toe at the rear. A very similar rear link design is used on Integrale. It may even be usable as a replacement although I have never checked the lengths.
Eric
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Hi
Just checked Haynes and rear camber is quoted as -30 minutes +- 20 minutes and front is +40 minutes to 1 degree 20 minutes. So looks like your camber is out as per diagram and I was correct on toe out for front wheels and toe in on rear. Your diagram shows different tolerances to Haynes for toe values.
Peter
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Hi Eric
Good point about the rear anti roll bar being adjustable on its attachment to the hub.
Peter
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Hi John
One last question (promise) are you running standard spacer at the front wheels and no spacer at the back as per original?
Peter
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No spacers have been added or removed.
All bushes replaced, a couple of bent bars straighten, new rear shocks... I'm reasonably confident with the diagnosis as if all 4 wheel were "straight" and fixed securely then I can't see what else it could be other than something flexing.
Rear wheel does look off vertical and I'll get a picture posted.
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Hi John
I still think you have the rear end setup wrong, ie it should toe in not out. Your original setup was way too much toe in at 1 degree, ideally should be around the 15 minutes by my quick calculation which sort of agrees with the chart, but as a toe in not out.
Peter
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Under the rear seats inside, is a cross beam that is welded to the sides and the floor. This hasn't rusted through has it, because that will allow the car to flex on the move rather than keep it rigid as all of the suspension set up (sway bar etc.) underneath then would be flexing wouldn't it?
C
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I'll have a look under the rear seats this weekend. I'm sure at least 1 wheel is pointing in the wrong direction so I might have a go at adjusting toe myself to make it more drivable (as opposed to not drivable)
Tyres lack date codes and are 185/65 so booked in Monday to get new tyres of original spec and revisit the alignment.
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Odd angle but this is me standing by rear nearside wheel looking down. My camera has a level in it so I know this was taken directly above and flat.
The spirit level is horizontal and touching each side of the wheel (tyre not rim). Red line is a good approximation of being parallel to the side of the car. 15 minutes toe in? I think not
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Hi John
Hmmmm…. Very little wonder the car is so erratic.
If you fancy a bit of home diy, you could use the string method of setting the car up. I did it for mine and it drives faultlessly and hence not at the vagaries of a company you do not know. Once you then know it can be setup to work then you could have it double checked.
PM me if you need any help doing it, pretty straight forward to do.
Peter
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Evening John
I’m not disputing your findings but. . . . You cannot setup or assess suspension angles by using the bodywork or other visual markers. It’s ‘very’ deceptive.
I have my own geometry setup equipment and have been tinkering with geometry on fwd Betas for 3 decades. I also calibrate my tracking/caster/camber equipment every time I use it.
Whilst I think it reasonable to question the reliability of the measurements you have been given, I think thorough visual checks under the car are the best place to start before you start moving tracking that allegedly isn’t far out.
As Peter has mentioned, the rear tracking needs to toe-in. Having said that, a little toe-out will not cause the car to ‘drift’. It will cause a fair amount of ‘lift-off oversteer’ when close to the limit but you won’t feel any noticeable unusual behaviour when driving sensibly.
Good luck
Ian
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Progress. Took it to another tyre place who confirmed tracking is way out. Also confirmed one of the (new) bushes in the cross member is/has failed. Also confirmed slight flex in cross member.
If anyone is interested I took a quick video but not sure how to post as it's 21Mb
Decided to bite the bullet and remove cross member, get it shot blasted and strengthen. What could possibly go wrong?
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Hi John
Post the vid on YouTube and link to it here.
Glad you have had your thoughts confirmed. I am guessing that it is one of the rear arms which are a sort of U shaped one which do look quite fragile compared to the earlier tubular ones?
Hopefully they will sort you out and get it to the point of driving ok.
Peter
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https://youtu.be/a_V3CAKxOxo
2 things to look for.
1) back right arm movement
2) cross member rocking
Hoping a refit / new bush solves 1) and unsure about 2) until I remove it
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Yep, that will not help the back end stability….
Peter
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The failed bush would make setting the tracking an impossible task.
As for the crossmember rocking, it’s normal if not ideal but check the nuts are tight to the chassis rails just for piece of mind (2x on either side).
Also remember to tighten the long bolts that pass through the bushes with the load of the car on the floor. Otherwise the bushes are twisted in a normally rested position and will fail prematurely.
Ian
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I seem to remember Eric? suggesting having a weight in the boot to load up the rear end before tightening. As you say the bushes will constantly under tension if you do not tighten them under load.
Peter
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Bushes are sub £10 so I'm going to swap them out anyway and have the offer of welding gear should I need to strengthen the bar.
Ian good to hear the rocking is not abnormal, and I'll check the bolts, plus what it's bolted to
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Ok, bush has disintegrated (left). I have a new bush (right) but it has a metal outer sleeve unlike the one fitted (which may have been incorrect
Does the new one look like the right one?
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Hi John
Yes I think so assuming you have measured the OD /hole ID. Glad you have found the cause.
Eric
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Just gone to press it in, checked measurements (thanks) and they differ a few mil inner and outer dimensions.
Mark shows out of stock so looking for alternatives
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I may have a spare arm, condition unknown. If that's a potential solution for you drop me a PM and I'll check tomorrow. I think it's in the shed!
Guy
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Interesting to see how this has developed. Have you paid the first place a visit to get a refund on what was evidently a poor job!
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Just gone to press it in, checked measurements (thanks) and they differ a few mil inner and outer dimensions.
Mark shows out of stock so looking for alternatives
Hi
Interesting, I wonder if that bush is from the earlier round arms? I would however have thought the inner diameter would be the same.
If Guy does not have a spare arm, I have the suspension off the Coupe which is the same and one of them probably has decent enough bushes to get you going, though I would change them whenever you can.
As to Mark, drop him a message as he may have some coming in?
Peter
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I have this arm. Neither bush is perfect but will be better than none at all. The bolt is partially out and stuck at the moment but I think I can persuade it to move later today if I can find the right diameter thick wall tube an an appropriate washer. I have a plan…
If you want it please PM me your address John.
Guy
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Hi Guy, Peter many thanks for the offer.
Car is on 4 stands as taking the opportunity to get wheels refurbished, new disks pads and possibly strengthen cross member. Finding out the 4 cotter pins in rear caliper wedges were missing, and front disks on order with Mark so I have a bit of time to track down a pair of bushes(after symmetry)
Good to see the diagrams as my new-original look a bit different.
If the offer of a flying visit is there though, seeing how it should look would be appreciated
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Hi John
Remember you can go with 4 adjustable links deleting the pressed links and the design was carried over to Integrales. Perhaps a conversation with Tanc Barret with the hole center to hole center dimensions to hand along with the bolt hole size which is the same both ends.
You probably then have options for brand new links with bushes fitted delivered. He will also have assorted rose joint options.
Given how rusted and weak many of the pressed links now are I would explore options with Tanc.
You might need to make a mod to hook up the rear brake balance valve but this would be in the easy category in my world.
Eric
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Hi John
I do not think you mean cotter pins, I suspect you mean the 4 small spring type which stop the wedges coming out? I think Mark also has those or you could just use a piece of wire ….
Peter
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This is what I mean and yes, bent bit of wire installed :)
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The originals are not R clips they are simply figure of 8 springs.
I have dug out the two rear supports I have. Both are ok to use with solid if old bushes which will get going in the short term. Message me if you want to have one.
Peter
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Thanks for all the offers of help and spare parts.
Cross Member blasted and ready for painted and new bushes now arrived (many thanks Mark) and doddle to fit.
Just need to put it all back together
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Progress, all reassembled, loaded, tightened, wheels back on before a final check and, errr..
https://youtu.be/EMt1xe7_HBg?feature=shared
Video shows rear bar flexing as I first grab right wheel and wiggle (in 3/9o'clock position), then do the same on left wheel.
Cross member to chassis is bolted tighter than Haynes misprint suggests although not yet followed a suggestion to add thick washers to spread load.
What I'm seeing is the cross member twisting along the length rather than rotating along the length. ie distortion rather than a solid bar not bolted tightly enough.
Does that sound about right?
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Hi John
I think considering where you cam from originally, I would accept it for now, get it tracked and see what the result is. Most of the lateral force will be at 6 o’clock, so I think you may be being too cautious, though I have not tried that on my Spider, but could do when I return to the U.K. also I assume you have both wheels off the ground which is also not real life. One quick question, did you tighten the bushes up with the rear end loaded up to avoid premature bush damage?
Peter
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I did, bit of 1" stick with right angled bracket whilst wheels off the ground.
Weather in UK looking good this weekend so a few local trips in order.
Thanks again
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Hi John
They all do that Sir.
Actually I have never seen that before and wonder if it would happen on mine if I tried it? Welded braces could stiffen up the box section, but the inside of the U section might need metal welded on to stop that happening. I did wonder if rust has weakened your part but it only looks like surface corrosion. I would expect the hefty rear Anti Roll Bar to stop that flexing, but I do wonder if that is normal?
Eric