Technical Croma springs

[kennethgordon]

I have just replaced my first broken spring on the off side front. The garage warned me it would boing a bit at first as I turn from lock to lock but that this will bed in.
However after turning the wheels fully to the left and then staightening them tthe car steers to the left. After applying full right lock the car steers to the right.
I do not fully understand the workings of a McPherson strut but this does not seem right to me.
Any info before I tackle the garage on Monday

 

[dave]

springs should be replaced in pairs

 

[lanciaman]

I would agree they really should be replaced in pairs - I didn't and 3 individually went within a space of 4 months or so, and no doubt the fourth will as well.

In saying that, when the fronts were replaced (3 months apart) by doing them singly had no effect on the steering geometry, any boinging or anything.

 

[DoIDon'tI]

Sounds like they didn't include the strut top bearing when they reassembled the strut - either that or they haven't reassembled it correctly. Springs should not cause this.

And yes, they should be replaced in pairs - not only because they sag slightly over time, but if one's gone then (as previously mentioned) usually the other's not far behind it. In addition, there are manufacturing differences between various makes of spring and you could end up with a different spring rate from one side of the car to the other. Not the end of the world but not ideal either.

 

[Caravadossi]

I have just replaced my first broken spring on the off side front ...

My o/s/f spring was declared “broken” at MoT(No.3) a few days back at 57.4K mls. I assumed they’d replace both, but a solo Kilen 12168 replaced the broken one - I didn’t query it. I’ve also recently noticed a sometime hands-off drift to left or right. But then can’t say if it was there before (with broken spring) – or maybe due to swopping wheels & tyres from back to front.

The Croma had a laser alignment check prior to buying it - & I thought I’d do another at 63K mls, in a few months time when new tyres will be on the front. But perhaps best with a new n/s/f spring.

---------------------
55 Prestigio 1.9/16v150 (58K mls)

 

[kennethgordon]

I take everyones point about replacing in pairs. The problem was initially misdiagnosed as the spring only broke at the very end and was not obvious. Consequently the drop links replaced so I think the garage were trying to keep costs down by only fitting one spring. With regard to the bearing I do not understand what this looks like and how it works and how wrong assembly could lead to the spring tensioning as the wheels are turned. Can someone give me a tutorial?

 

[DoIDon'tI]

The bearing at the top of the strut allows the whole strut to turn when the steering is moved. Any restriction in bearing movement will cause a 'drag' when the steering is moved - this will stop the steering from returning to the straight ahead position by itself. The spring rate should never be altered by steering movement, the spring itself should not be subjected to twisting loads as this will cause fatigue. Try twisting a small spring in your fingers and you'll see the effect.

It's not unheard of for a seized track rod end to cause the same symptoms. Without looking at (or driving) the car, it's very difficult to diagnose - sorry. As for what the bearing looks like, it's a large roller bearing between the spring and top mount which allows the spring to rotate relative to the top mount. At least, that's what the ones on Vectras are like, I can't see Cromas being any different.

There are several variations on the McPherson strut theme but having the spring rate affected by what direction the steering is turned is generally regarded as a bad thing More to the point, it leads to 'boinging' noises as the spring moves slightly and eventually causes spring breakages

Finally, there is a possibility that the strut was assembled incorrectly with the strut piston not located in the top mount properly, and this off-centre mounting is jamming the strut from moving correctly.

Whatever the cause, it needs looking at to find the source of the restriction. If it wasn't there before the strut was rebuilt then it's a reasonable assumption that something wasn't put together right. Please let us know how you get on

 

[kennethgordon]

Thanks for that very detailed description. I have since found a Haynes manual of my Fiat Marea (Brava) and despite the very grainy pictures I can see the roller bearing and plates. I spoke to the mechanic today (who has done many Vectras) and he cannot explain the symptoms other than the bearing being damaged or not reseated properly.
Any road up, it goes in on Wednesday for a strip down. At present we are all still talking.

 

[kennethgordon]

All is well. The garage simply dismantled the spring assembly and 'reseated' the spring in the top plate. Thanks for your help in this matter.

 

[dave]

do vectra lowering kits fit cromas?

 

[Chris@souls]

do vectra lowering kits fit cromas?

Id imagine so, all the standard stuff has GM plastered all over it

 

[dave]

Id imagine so, all the standard stuff has GM plastered all over it

cool am getting cravings for a black one slammed, debaged and decromed

 

[s130]

Well I knew my time was coming.

Today, reversing off the drive a horrible noise. Grate/grind. Stop in road and look inside the wheel arch.....broken spring! (front offside).

Will have to wait till Monday to see what my local motor factors can get, meanwhile tomorrow will be a Google day

Half of me wants to claim against Fiat as this is no an inherrant fault and as such in the UK is not restricted by a warranty period. However going that route takes time and you end up with a crap GM/Fiat spring replacement for all your trouble.

Think I'm tempted to just go ahead and replace them (possibly all 4) and bill Fiat for parts and my labour afterwards.

Now all I need to do if find a good quality spring! Any suggestions?

 

[JOHN COOPER]

Eibach springs the best of the best. thats what i use at my garage for bmw/mini.

 

[s130]

Just got 4 new springs.

Phoned my local parts factor this morning. Springs arrived early afternoon.

Set of 4 Kilen springs (http://www.kilensprings.com or http://automotive.lesjoforsab.com)

Total cost of £169.74 (trade).

A check on latest ePER shows that Fiat no longer supply springs alone for the front and will only supply a complete strut at MEGA BUCKS!

Now comes the fun fitting. I see that eLearn claims some of the bolts require replacing but I've found no garages Fiat/GM that actually replace them unless they are damaged or obviously over stretched.

I'm hoping that rears are simpler than eLearn suggests. They use a deepish rear sping compressor to compress the spring in situe. I'm hoping that removing the shock lower bolt will allow the suspension to drop down enough to just remove the spring. This is how I've changed rear springs in the past. Dead simple. Local garage also claims this is all that is required. Time will tell.

Final more intricate and added expense is all 4 wheel tracking. The rear as we all know is a real tyre wearer and I'm guessing that in the last five years the rear springs have sagged a little and this affects both camber and toe. I can check front and rear tracking fairly easily but camber is difficult to get right / measure. Requires accurate all wheel leveling of the car.

Guess I measure all the toes and if still OK then decide if I take a risk or just take a longish drive to my favourite 4 wheel alignment shop and write another check for yet more money!

Just wish the spring had failed before I had all the tyres and geometry setup a short while ago.

 

[Hellcat]

The Corma is in a garage getting an MOT and having its rear shocks replaced During the MOT they found a cracked spring on the rear.

The garage said they will swap the springs for new while they have the shocks off, so I would suggest the arms will drop lower if you take off the shocks. No doubt some garages would charge you fitting for both shocks and springs, so thanks to Barry and Paul again for keeping us on the road and money more or less in our wallets

The shocks we have bought are Bilstein OEMs.

edit: as if by magic, their advert pops up in the banner!

 

[notorious]

I fitted b4's and they were same catalogue numbers for Vectra C and Croma

 

[Hellcat]

Other manufacturers dont list them as the same part - only Bilstein.

 

[s130]

One front strut done, other half done....

Looking at the unbroken spring it is clearly rusting at the lower point where is just leaves the strut saddle. This is obvioulsy the highest stread area and the sping flexing is causing the original paint (power coated ???) to fracture and allow water in.

New springs are suposedly powder coated but if this area just above the saddle is still a high stress area for the new springs, possibly due to saddle design, then we could be looking a more spring failures in the future.

Anybody tried rust preventive methods, like by liberally greasing this area in waterproof moly grease?

 

[s130]

All the front springs done now. Will need the tracking redone all around ......

Has anybody here PERSONALLY change the rear springs themself?

If so was it as simple as removing the lower rear shock absorber bolt and pulling the arm and hub down to withdraw the spring (with or without spring clamp) or did you have to split the suspension somewhere else as well.