Technical bouncy bouncy wobbly wheels

[franglais]

Hello again,
i have wheel judder, it crops up at about 45 - 50mph (75-80kph) and so is not a problem 99% of the time, i rarely drive at that speed, but it's noticable as i accelerate through and wont be doing my bearings or suspension any good. it's only recently i noticed it, although as i said, i rarely drive at that speed and so might have just never paid it any attention or put it down to bumpy roads, and only now (i changed job and so take a now have kind of commute) it's come to light.
i went to the garage where i had the tyres fitted (i trust them) and they rebalanced my wheels (for free) but if anything, it seems worse than before. i had the impression that it was more in the steering wheel before the rebalance, and now it is definitely more in the body, i can feel the whole car bouncing where-as the steering wheel hardly moves.
could it be the back wheels causing this problem? maybe one of the weights has fallen off? my only other hunch is that the wheel nuts could be causing it, on one wheel, i have 3 normal 19mm nuts, and one 17mm (no idea how, i bought the car like that) but like i said, i have never noticed the problem before and so i doubt that could be the sole cause.

i was thinking of trying a home made wheel balancing test, jack one wheel off the ground stick it in 5th and accelerate to 78kph and see if there's any visual imbalance. i could take out the odd nut and it's opposite counterpart to eliminate that from the search, do any of you people have any other ideas of things to do or look at?

PS i've still not had enough good weather to sort out the injector pump leak, this will be doing my fuelly litres per/100Km charts no good whats-so-ever!

 

[Plbmak]

Do you have a spare? Do some swapping around, and yes, it could be a rear. My first port of call would be to go to another tyre place, just for a check. If not tyres, check ALL your suspension joints and bearings.

 

[bpetersb]

I had a similar judder on a car many years ago and it turned out to be rear wheel balance, the whole front end of the car would shake violently which is why it took me so long to find the problem. Worth getting the rears balanced if only to discount it. Good luck

 

[franglais]

yes, i will ring the garage tomorrow and see when they can do it, i had a look at the spare, and it's one of those emergency spares, it's not a full sized wheel and the tyre is rated to 40mph only, i could try swapping front to back left to right etc, but it would be easier to just pay £20 and have the garage do it in 10 minutes.
interestingly, i have noticed that sometimes it comes and goes, at first i thought it was the road surface playing a part, but i'm doubting that now, i've been noticing that when going round a bend, it will get worse or better and then back again, and when going in a straight line, the amount of vibration stays fairly constant, it seems that the wheels are syncing up to cancel out/accentuate the amount of oscillation.
it's funny how the front end is always the first to get the blame in these situations eh?
thanks for the replies.

 

[varesecrazy]

chances are you've got a slight imbalance in 2 wheels, and it's when they both get in-sync you get the bad vibes..,

I had this on an old fiesta - needed it sorted - and got 2 replacement wheels in the end!

swapping front to back may highlight the issue,

Charlie

 

[franglais]

i went back to the garage and they checked the back wheels, a very slight imbalance but nothing to be concerned about, they changed the weights to correct it, but still no joy.
we took the opportunity to check for play in the bearings while all 4 wheels were off the ground, nothing important.
they told me that had a Fiat Palio which did exactly the same thing at almost exactly the same speed. some hard web searching shall be taking place.....

 

[varesecrazy]

swapping the wheels around may still help..,
beware of directional tyres though..!!,

Charlie

 

[franglais]

well today was fairly uneventful, spent most of the weekend looking to get the injector pump leak fixed, but i couldn't get the clip off the oil vapor recirculator (black thing in front of fuel filter) and so couldnt get the mounting plate bolt off the injector pump, i shall have to tempt driving another week to work with a sickly pump :/
the wheel wobble is no nearer a solution either, im fairly certain it's failing bearings, but i cant be quite sure which ones yet. There is a slight change in sound when i go round a bend, but i can't distinguish it from a change in the tyre noise, it's subtle enough to be either. After taking the wheels off and revving the engine in 5th, the brake calipers do visibly wobble a couple of mm at certain speeds. i've had a tug on all the connecting CV joints, and found no play in any of them. on a side note, i did notice however that the gearbox makes quite a racket when spinning the wheels, is that normal under no load?
i think i might just have to wait until the problem gets worse to find the culprit.

i moved on to sorting out the glowplug problem, i was hoping to do this at the same time as having the injector pump out, mkaing access much easier, but having made such slow progress, and with the commute looming, i hurried the car back together and spent the last hour before sunset fiddling.
I have no idea of the piston number but the one nearest the timing belt was quite accessible (relatively, they are all AWFUL to get to) and i managed to take it out without too much trouble, tested it on the battery and it glowed up straight away that would have been too easy. So the next one along i though might just be possible, and with a lot of tinkering and a small amount of swearing, i got that one out too, checked it like before, and nothing, not even a spark when touching wires to it, DEAD. excellent, i whipped out the new bosch glowplugs and the swine would not for anything, screw back in, i tried and tried, i compared sizes, made sure the thread was exactly the same, all sorts, i just could not get it in, so i tried the old one, no problem, easy as pie, so i went back to swearing and getting frustrated as the sun was going down, and the pig decided to fall into the engine and not come out the bottom, i have a good lamp and a strong magnet on a flexible extension, and i could not find the little bugger. so i put the old one back in and gave up. :bang:

 

[varesecrazy]

we tried to change the plugs on outr JTD..,
took em out,
drove around 8 local places..nobody stocked the correct ones,
drove home.. then dropped 1 just like you,

took over an hour to find it perched on summat halfway down engine.. unfortunately need all 4 back in place ; - },

Charlie

 

[franglais]

took over an hour to find it perched on summat halfway down engine.. unfortunately need all 4 back in place ; - },

haha what a nightmare

i was following a tractor yesterday on a nice smooth road and noticed at about 35-40kmph the right hand side of the car bounced more than the left, that narrows it down a little and confirms my suspicion. i WILL find this annoying little bug!!! a little bit of daylight when i get home from work would be nice though :bang:

 

[franglais]

small update, i figured out why the new glowplugs wouldn't fit, the old NGK ones have no taper on the heating element, and the new bosch ones have a 1 or 2mm taper starting about 5mm from the tip, and so get trapped just before the thread catches. well i got fed up of looking for new glowplugs in the local shops, and the internet catalogue i usually use, seems to have only the glowplugs with a shoulder too, so i went all jeremy clarkson on the one i have, and stuck it in my cordless drill, made sure there was no wobble while spinning, and (gently) took my angle grinder to it!! GGGRRAAAAHHH :devil::slayer::slayer:
here's some new NGK plugs (which will apparently fit a TD100) with the taper/shoulder 5 to 10mm from the tip of the plug http://www.oscaro.com/Catalog/Part/GetGallery?idArticle=617370&show3d=True

i put the new plug in hassle free this time, then fired up the motor, only to discover i have at least one more faulty plug to find the next ones won't be so easy, do i have to take off the inlet manifold?

 

[franglais]

it's been too long that i haven't updated this thread, i figured out a while ago that it was the tyres which are egg shaped, this can be seen easily when running the car in 1st gear while on axle stands, i confirmed this today as my new wagon came with dead front tyres so i swapped my old wheels over to delay shelling out even more cash this month. the wobble has come back.
mystery solved, thread can be closed.

 

[bpetersb]

I wouldn't use that garage/ tyre dealer again, having balanced a lot of wheels it is always obvious when a wheel is buckled or a tyre is out of true when you spin it up on the balancer. The fitter was either not paying attention or didn't care.