www.gt4dc.co.uk
Maintain, Modify and DRIVE your GT-Four


It is currently Mon Oct 23, 2017 1:40 am




Post new topic Reply to topic  [ 13 posts ] 
Author Message
PostPosted: Fri Nov 04, 2016 9:44 pm 
Offline
New Poster

Joined: Sat Aug 13, 2016 8:14 am
Posts: 6
Car Model: None
Hello Again. (edit, apparently this is my first post actually)

My ST205 is now on the road.
I have a clunking noise from the passenger side when braking. (most of the time but not always)
as well as another clunk from the driver's side when turning the steering when parking.

I know the Fig8 were replaced in the past. however no record in the paperwork for anything else.

In the Celica club UK forum, i have posted asking for help with this situation and the replies i got were.... well... helpfull.... but also expencive.

One of the members suggested "Most of the more techie geeks are at http://www.gt4dc.co.uk" So, im hoping a discussion in here may lead to some insight into the problem. with technical/engineering/mechanical knowledge which ,in my best hope, will allow me to save a small fortune.

From the discussion on the other side, im told the SS arms are all very sturdy and unlikely to be damaged.
I asked "why cant we just replace the bushes then?" to which the answer was more or less "they are nearly impossible to replace"

Id like to build up my knowledge from this point in order to figure out how to proceed ref this clunking noise.

To my understanding, bushes are designed to be replaced, therefore being "impossible" to swap bushes sounds odd.

I understand the WRC GT4 version has a different suspension setup (mcpherson? ) which is the same as the GT and ST, under the assumption the refurb route is not possible for a DIYer, is it possible to swap the suspension from a ST/GT to an GT4 ?

In short, my questions at the moment are.

Why is it "impossible" to swap the bushes from the SS arms ?
Is the ST/GT suspension a "bolt on" swap alternative for the GT4 ?

I don't have a engineer or mechanic background, I have a working understanding of cars from working on both this ST205 and a lotus elan, so don't be afraid of explaining things on a technical way, there is always google to help if needed.


Any input you guys have is appreciated.

and apologies for such long post with ideas scattered all around. I did try to organize it, but there is a (very small) limit to my organizational skills.


Top
 Profile  
 
PostPosted: Fri Nov 04, 2016 11:13 pm 
Offline
Group B
User avatar

Joined: Sat Sep 02, 2006 3:13 pm
Posts: 3580
Location: Bournemouth
Car Model: None
Some joints can be replaced, and these are what is done on most of the refurb units. These are often not what wears out however so refurb ones often don't last long before the non replacable items fail. These are generally considered false ecconomy for this reason.

There are a number of joints which can fail causing similar symptoms. Generally, any clunking at the front is referred to as 'fig 8 failure' and all parts are replaced as the other bits would wear out soon. IMO this is a little silly as I've never come across another car where it is normal to replace the entire suspension setup when the first joint fails. I can, however see the arguement if you want the car to be in tip top condition and not need to be constantly replacing parts individually as they wear out.

The 'fig 8 failure' normally refers to failure of the joint which is part of the fig 8, or failure of the joint which is in the middle of the lower arm connecting to the other end of the fig 8. Play in either of these allows the bottom of the strut to move making the clunking noise and allowing the steering to wander. These joints are part of the arm and cannot be replaced without major engineering effort likely to weaken the arm.
The inner end of the lower arm is a spherical bushing which I thank can be changed if replacements are available. Don't get a polybushed one as this will be softer than standard. The outer end is a ball joint which again is built into the arm and the same applies as the centre joint.

The other expensive part is the tie bar or 'banana arm'. At the strut end is another ball joint built into the arm. At the chassis end is a very strange rubber bush joint, often referred to as 'crush tube'. It is actually a normal rubber void bush but used sideways, and the inner metal tube is much larger than the bolt. A 'crush tube' (thin metal tube which is a tight fit inside the void bush and the large holse in the chassis) holds the bush in place while the bolt is tightened. This joint relies on a combination of the weak metal tube and friction from the ends of the inner tube to hold the arm in place. Hitting a pothole often overcomes the strength available leading to the arm being able to slide in & out. Again, this produces a knocking noise. It is easy to test for this, just try to roll the front wheel backwards & forwards while the car is still and steering straight. There are a number of theories why Toyota did this, the most popular is it being a 'fuse' which gives before chassis damage occurs. The number of these that fail tell me that it isn't a good design as once the damage has occurred, the movement very quickly wears & damages the chassis anyway.

All GT4 ST205 have superstrut, including the WRC model so there is no easy change to a normal McPherson setup. It would require a swap with a non GT4 celica and would lose the improved brakes of the GT4. Regarding the details, you would probably get more information from the celica club as I know people have interchanged the SS and McPherson on the normal celicas, although the GT4 may have different driveshafts.

personally, I wouldn't consider swapping away from superstrut and accepting worse braking for the potential cost saving. The initial cost to buy all the non SS parts (including brakes, hubs, struts etc.) would probably be as much as, if not more than, and entire new SS set which should last at least 60K miles. If you only change parts as needed, then I would expect to be at least 100K miles before you've saved any money. The cost of 100K miles of petrol will make the cost of the SS pale into insignificance.

_________________
If at first you don't suck seed, try drier grain.

Image


Top
 Profile  
 
PostPosted: Sun Nov 06, 2016 7:05 pm 
Offline
New Poster

Joined: Sat Aug 13, 2016 8:14 am
Posts: 6
Car Model: None
Hi Nibbles.

you probably have realised by now i am trying my best to avoid the big bill, if i manage that, there is hope for everyone else. so my first step is to gather information from everyone who has experiences this issue in the past.

according to the Celica page on wikipedia it states "Instead using the Super Strut Suspension as found in the production cars, the actual ST205 rally cars for WRC came with standard strut suspension as they found the wear rates too high from the rigors of rallying"
I had a look at the references, and the only one ref the st205 didn't mention anything in particular about the suspension.

Do you know this from experience?

I find it odd to see conflicting information between wiki page and someone with the amount of knowledge you just demonstrated.

with that detail aside. I wasn't aware switching suspension setup would compromise the use of the ST205 callipers. so knowing that now, I am no longer considering the swap.

which brings me back to the joints/bushes.
could you please confirm
is the joint that connects the no1 arm to the fig8 link (i will refer to it as the A-join from now), part of the no1 arm, or a joint that is pressed into the arm (and extremely difficult to remove)?

when fully functional, is there any movement allowed in the A-joint ? if there is, is this movement the same as the normal movement a ball joint would allow ?

the other joint on the no1 arm at the side of the wheel, (will refer as B-joint) is this a normal ball joint as in a McPherson setup?

I would also like to know if the joint on the fig8 link is the same as the A-joint

I am able to acquire a set of no1 arms and banana bars from another owner who had he's replaced upon failure, i've been thinking about the possibility of refurbishing these to swap with mine which currently are making the clunking noises.

I suspect the nearside of my car to have failed with the crush bar issue previously mentioned as my local mechanic mentioned there was some free play at that specific joint.

I am referring the following picture in order to try and understand the setup and why refurbishing these is "impossible"
http://www.gt4-racing.eu/images/st205-s ... lica-2.jpg

In short, I am trying to understand why its not possible to refurbish the suspension effectively, If i understand it, then i will probably end up ditching the money out, but if it doesn't make sense to me, and with enough information, i may buy the used set previously mentioned, and attempt to refurbish myself in the hope to save a fortune.


Top
 Profile  
 
PostPosted: Sun Nov 06, 2016 8:21 pm 
Offline
Group B
User avatar

Joined: Sat Sep 02, 2006 3:13 pm
Posts: 3580
Location: Bournemouth
Car Model: None
The actual cars used in the WRC didn't use the superstrut, but it was all custom made and the cost probably had a few zeros on the end. Saying that, I think they may have used superstrut on tarmac as it keeps the suspension geometry better and tarmac is more critical.

The McPherson has a single lower swivel which sticks out much further than the twin swivel on the SS setup. If you try fitting a 205 disk on a McPherson hub it fouls this swivel. If you search for information on upgrading the brakes on a 185 you'll see the pain. There are a number of option, but they are all effectively bodges requiring spacers behind disks or shallower disks (avensis or audi TT) and alternative or machined calipers plus a custom bracket.

A joint - I'm not 100% certain whether this is a pressed in insert or machined into the arm, I haven't pulled one apart. When I have heard of people changing an A joint or B joint it has involved machining the arm to take a standard part. Knowing that breakage of this arm could easily lead to a nasty accident, it isn't a course of action I would take or reccomend.

The A joint allows rotation only, as does the joint at the other end of the fig 8. When funtioning correctly, they hold the bottom of the strut so it cant turn or rock forwards/backwards or in/out - it can only go up/down. This is then connected to the top of the hub via a replacable ball joint (These also wear).

B joint - this is a standard ball joint as is normally found in McPherson setups, but it is not the replacable one used on the Celica McPherson. It is built into the arm as above.


The best way to save money if you are doing the work yourself is to find out which joint has play in it and just change the required part. Some of the joints will probably last twice as long as he first to fail.

There has been much discussion about crush tubes. In my opinion the best option of those available is to use the 'uprated crush tubes' available fron a number of places. These are basically a solid version which won't give and allow the arm to move. Make sure the inside of the arm is thoroughly clean so the tube slides in & out easily and use plenty of grease when assembling otherwise you'll never get the arms out again without removing the entire subframe.
If someone fancies doing some engineering, then I would suggest getting shoulder bolts made (i.e. bolt + uprated crush tube in one piece). This will get rid of the problems of geting crush tubes back out again.

_________________
If at first you don't suck seed, try drier grain.

Image


Top
 Profile  
 
PostPosted: Sun Nov 06, 2016 9:07 pm 
Offline
New Poster

Joined: Sat Aug 13, 2016 8:14 am
Posts: 6
Car Model: None
Thanks for the clarifications.

once I have confirmed its the crush tube, i will probably go the route of those uprated ones mentioned.

Am i correct to assume when the A-joint fails (or gets loose), welding it in place is not suitable because the metals available to weld cannot sustain the forces exerted in the joint ?

here is a link to the used set previously mentioned.
Image
From the picture it looks like the A-joint has a rubber boot, which seems odd considering the forces applied to it are rotational.

I am likely to swap whichever part is needed with a new one. so far im trying to understand why refurbishing seems to be impossible, as for the cost of parts, and depending on where the failure is, i would much rather refurbish than potentially spend 350 quid on "a metal bar".

Also, this may be a much more important question. should I stop driving the car completely until i fix these noises, or is it ok to drive in these conditions as long as I don't do any sharp turns at speed ?

So far i drove to work twice with the car, there was no noticeable problem in the steering comparing to my SR, and the grip around the roundabout near work was better than my Lotus, basically, as a driving car, the only issue i can pinpoint is the noises, nothing wrong with the drive-ability, and since my SR runs out of insurance and tax next month, i was hoping to drive the GT4 instead daily.

*EDIT*
forgot to mention, my drive to work is basically 2 miles city, then 18 on motorway, the only turn that allows for any kind of spirited driving is the roundabout to the motorway, basically I've done 80 miles on the car so far.


Last edited by tuga2112 on Sun Nov 06, 2016 11:20 pm, edited 1 time in total.

Top
 Profile  
 
PostPosted: Sun Nov 06, 2016 11:09 pm 
Offline
Group B
User avatar

Joined: Sat Sep 02, 2006 3:13 pm
Posts: 3580
Location: Bournemouth
Car Model: None
Assuming the clunking is just play due to wear then you shouldn't have a problem driving it, you may just find it wanders a little at higher speed.
Bear in mond though, that if it's crush tube joint failure you will be wearing away the void bush inner and the subframe as they slide against each other so it's better to do it sooner rather than later. The uprated crush tubes are pretty cheap and it's not a huge job to change them.

IMO it's worth diagnosing exactly which joints do have play so you have at least checked it's not bolts coming loose or something broken.

The Celica club link doesn't work by the way, just comes up with a 404 error (and I am logged in on it).

_________________
If at first you don't suck seed, try drier grain.

Image


Top
 Profile  
 
PostPosted: Sun Nov 06, 2016 11:23 pm 
Offline
New Poster

Joined: Sat Aug 13, 2016 8:14 am
Posts: 6
Car Model: None
ive re-uploaded the picture in tinypic. it should now be visible.

In that case i will avoid using it untill i can be sure what the problem is, good thing my SR is still road legal for a month.


Top
 Profile  
 
PostPosted: Thu Dec 22, 2016 1:45 am 
Offline
New Poster

Joined: Sat Aug 13, 2016 8:14 am
Posts: 6
Car Model: None
finally got the time to put the car on jacks and had a look

i *think* the crush tube is fine. but the bush on the banana arm seems to be gone.

this is a picture of the side that does the clunking noise every time i break
Image

this is a picture of the opposite side
Image

from the pictures both sides seem to be equally worn, but from visual inspection, the "clunking side" seemed to not have any rubber at all left, while the "good side" still had a ring of black in the area.

i would like a second opinion on this before starting to take the suspension apart, because by hand, i cannot see or feel that there is anything "loose" or moving too much.


Top
 Profile  
 
PostPosted: Thu Dec 22, 2016 4:44 am 
Offline
Clubman
User avatar

Joined: Wed Dec 14, 2016 8:25 am
Posts: 78
Location: Russia, Izhevsk
Car Model: ST205
Rubber silent block in the banana lever can produce a knock in only one case - if the bolt is not spun or twisted slightly.
This thin-walled sleeve is not fulfilling hub crushing is used only for centering bushings in the subframe mounting, no longer functions, because the bolt has twisted and Hob standing rigidly in a stretcher.
Check my topic. You'll find the answers to their questions: viewtopic.php?f=1&t=7688

_________________
vad07@inbox.ru


Top
 Profile  
 
PostPosted: Thu Dec 22, 2016 9:09 am 
Offline
New Poster

Joined: Sat Aug 13, 2016 8:14 am
Posts: 6
Car Model: None
бешаный 202 wrote:
Rubber silent block in the banana lever can produce a knock in only one case - if the bolt is not spun or twisted slightly.
This thin-walled sleeve is not fulfilling hub crushing is used only for centering bushings in the subframe mounting, no longer functions, because the bolt has twisted and Hob standing rigidly in a stretcher.
Check my topic. You'll find the answers to their questions: viewtopic.php?f=1&t=7688

Had a look at the post you mentioned, I'm very happy to see you managed to fully rebuild the sss and mane it in a way that allows further rebuild easy, I would love to be capable of such thing.

I don't fully understand what you mean on the reply, are you trying to say that nothing looks wrong from my pictures and probably the bolt that holds the banana arm needs to be tightened?


Top
 Profile  
 
PostPosted: Thu Dec 22, 2016 9:22 am 
Offline
Clubman
User avatar

Joined: Wed Dec 14, 2016 8:25 am
Posts: 78
Location: Russia, Izhevsk
Car Model: ST205
I can make such suspension arms for you.
In the picture it is difficult to assess the situation correctly.
If the rubber joint is smooth and well-screwed bolt, it can not issue a knock.
But if the bolt slightly twisted or rubber joint is initially crooked, then when you turn the steering wheel under your foot, you feel the clicks, as well as when starting and braking of the car.
Generally SSS difficult to diagnose when it is set to car.
It is easier to understand when the SSS is completely removed from the car and disengaged from each other.

_________________
vad07@inbox.ru


Top
 Profile  
 
PostPosted: Fri Dec 23, 2016 5:57 pm 
Offline
Group N

Joined: Sat Jul 16, 2011 8:13 am
Posts: 187
Location: North East (Cullercoats)
Car Model: ST185 CS/RC
Quote from бешаный 202... I can make such suspension arms for you.
Please advise a cost (in UK£) how much including postage please?
Sorry Tuga 212... we all have this problem :)

_________________
UK WRC & a CS :)


Top
 Profile  
 
PostPosted: Fri Dec 23, 2016 6:28 pm 
Offline
Clubman
User avatar

Joined: Wed Dec 14, 2016 8:25 am
Posts: 78
Location: Russia, Izhevsk
Car Model: ST205
I answered a personal message.
Payment for delivery to your significant :(

_________________
vad07@inbox.ru


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 13 posts ] 


Who is online

Users browsing this forum: No registered users and 1 guest


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum

Search for:
Jump to:  
cron
Powered by phpBB® Forum Software © phpBB Group