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Yes you did sirias...its just as it only makes the noise when going over uneven roads and only on passenger side,/that keeps throwing me towards suspension
Technical Knocking still after wishbones
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Technical Knocking still after wishbones
How much play is there BMS?
Only the inner joints should move in/out (to allow for suspension movement), the outer (Hub-end) CVs should have no significant longitudinal play.
You will always get a tiny amount of movement, but it shouldn't 'float' in the same way the inner one does.
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What do you mean by play in outer CV?
By just grabbing the shaft and pulling and pushing there's movement...the boots are still on so can't see where the movement is..
But as said both shafts have similar movement but only get the noise when passenger side is affected..
I may take the suspension leg off tonight if I get a chance and have a look before I splash out on driveshafts
By just grabbing the shaft and pulling and pushing there's movement...the boots are still on so can't see where the movement is..
But as said both shafts have similar movement but only get the noise when passenger side is affected..
I may take the suspension leg off tonight if I get a chance and have a look before I splash out on driveshafts
Are you saying you're seeing movement in the outer boots, when you grab the halfshafts and push them side to side (i.e. across the line of the car)?
The outer CV's can be replaced on their own and they're cheap (less than £20 each inc. VAT & delivery). There's no need to replace the entire halfshaft.
The outer CV's can be replaced on their own and they're cheap (less than £20 each inc. VAT & delivery). There's no need to replace the entire halfshaft.
The outer (Hub end) CV joints look like this . . .
The Spline on the Driveshaft is secured to the centre section of the Joint by a Circlip.
Because of the spherical design of the Joint assembly, it can swivel in any direction, but it can't move in/out (other than a very small amount due to the clearances involved).
The inner (Gearbox end) joint looks like this . . .
Usually called a 'Tripod Joint', for obvious reasons (or Tri-Pot in the US).
The Driveshaft mates with the Splines on the three-legged (Tripod) part, the Shaft on the left is the output shaft from the Gearbox.
It allows for slight angular movement (due to suspension travel), but also allows for the Driveshaft sliding in and out, due to the distance changes between the Wheel Hub and Gearbox as the suspension compresses and extends.
The longer the suspension travel, the more that distance changes.
So the Hub CV should prevent the Driveshaft moving in/out when you push/pull on it.
If there's any significant movement (more than say a mm or so), then it's badly worn, or the Circlip isn't fitted.
This video explains it pretty well, in the first 6 mins or so . . .
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Bikedoc..are you sure u aren't a car god?
There is definite play in the joint hub end as I can hear it knocking against the hub.. Movement though is very little and its Max 5mm of.movement and nothing up and down..same drivers side..
Really has stumped me and the hate being beaten...
Wish I had another multi to compare it with
There is definite play in the joint hub end as I can hear it knocking against the hub.. Movement though is very little and its Max 5mm of.movement and nothing up and down..same drivers side..
Really has stumped me and the hate being beaten...
Wish I had another multi to compare it with
Definitely not!
I've been around and under a good few in my time though (and Bikes).
Started when I was about Eight/Nine, helping my late Father fix his cars.
He was a proper 'Make-do-and-mend' type, like a lot of people of his era (that lived through WWII).
Buying a new part was always the last resort, if it couldn't be fixed, modified, replaced with a home-made one, or done away with altogether!
He'd take things apart just for the fun of seeing how they worked sometimes, I'm exactly the same
5mm is probably on the limit for wear I reckon, but if it's not knocking/grinding when you're turning (1/3 to full lock sort of turning), I'd leave them.
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Well...there is no knocking on full lock, which keeps swaying me from the driveshaft..
So today I nipped to da motors and bought a complete suspension leg.
Fitted it and the noise seems to have gone...but not taken it for an extensive drive yet...finger crossed.
I've taken the spring off the old shock...and I can easily compress the shock and on extension there seems no resistance..also fully extended, there is some sideways play and knocking..
So today I nipped to da motors and bought a complete suspension leg.
Fitted it and the noise seems to have gone...but not taken it for an extensive drive yet...finger crossed.
I've taken the spring off the old shock...and I can easily compress the shock and on extension there seems no resistance..also fully extended, there is some sideways play and knocking..
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After an extensive drive its now silent..
Thanks for all you help and advice guys..it was the shock that was knackered...add it to the list of things to change when a knocking is heard
Thanks for all you help and advice guys..it was the shock that was knackered...add it to the list of things to change when a knocking is heard
Cool on fixing it, good feeling when you sort them problems out there the type that do send you mad, was there no leaks any where when you inspected it, you would think the seals would wear and let something out if it moves sideways, ?
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No visible leaks what so ever and it looked visually in very good condition...a lot less rust than the one from da motors!
Also aren't these gas struts?? So would there be any fluid leak?
It is a great feeling as it was really getting to me! Hate being beaten.
Also aren't these gas struts?? So would there be any fluid leak?
It is a great feeling as it was really getting to me! Hate being beaten.
I hate being beaten no what you mean, done my clutch in mid December god it was cold I almost give up and towed it to the garage but I had a brew warmed up and got stuck in
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The OEM Fiat struts are oil filled.
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Don't doubt your knowledge WMF, but are you sure? My struts bare bone dry but are definitely knackered
Only from what I've seen on other threads. There was another one some time ago where somebody (could have been Thirkell?) had very similar symptoms to yours and it also turned out to be a shot strut that time as well. An oil filled damper doesn't have to leak if it's knackered. The internal valving and guides can give up but the outer seal for the rod remain intact. It sounds as though something along those lines has happened in your case.
Also, this is from the FAQ's on Monroe's pages:
"A service technician said my struts had failed and were leaking oil; however, my vehicle has gas charged struts. Could this be true? Yes, gas charged shocks / struts contain the same amount of oil as standard hydraulic units do. Gas pressure is added to the unit in order to control a condition referred to as "shock fade," which occurs when the oil in a shock or strut foams due to agitation, excessive heat, and low pressure areas which develop behind the piston (aeration). The gas pressure compresses air bubbles trapped within the oil until they are so small that they do not affect the shock's performance. This allows the unit to ride better and to perform more consistently."
The Bilstein dampers I've fitted to mine are oil filled. I think I'm right in saying the Monroe ones for the Multi are too. KYB's are gas filled, or at least one of their models is. In theory the gas filled ones should be better. In practice, the quality of the engineering has a greater effect. I've got no complaints about my Bilsteins....
Also, this is from the FAQ's on Monroe's pages:
"A service technician said my struts had failed and were leaking oil; however, my vehicle has gas charged struts. Could this be true? Yes, gas charged shocks / struts contain the same amount of oil as standard hydraulic units do. Gas pressure is added to the unit in order to control a condition referred to as "shock fade," which occurs when the oil in a shock or strut foams due to agitation, excessive heat, and low pressure areas which develop behind the piston (aeration). The gas pressure compresses air bubbles trapped within the oil until they are so small that they do not affect the shock's performance. This allows the unit to ride better and to perform more consistently."
The Bilstein dampers I've fitted to mine are oil filled. I think I'm right in saying the Monroe ones for the Multi are too. KYB's are gas filled, or at least one of their models is. In theory the gas filled ones should be better. In practice, the quality of the engineering has a greater effect. I've got no complaints about my Bilsteins....
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RE: someone on here with a similar problem - it was more recent than I thought (which is probably why I remembered it!) :
https://www.fiatforum.com/multipla/424273-multipla-n-side-suspension-knock.html?p=4067042
https://www.fiatforum.com/multipla/424273-multipla-n-side-suspension-knock.html?p=4067042
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Yep that's what made me swerve the driveshafts...even though there is sideways play in them..
A true 'Gas Strut' doesn't have any Oil in it (other than a very small amount for lubing the piston), it's what you'll find under your office chair, or holding up your Bonnet/Tailgate.
Gas struts for Suspension are Oil-damped, and as WMF pointed out, there is pressurised gas to control 'Aeration' or 'Emulsification' of the oil.
Cheaper gas shocks just have the gas mixed in with the oil, they're called the 'Emulsion' types. (Left in pic)
The best Shocks have the gas separated from the oil by another 'free-floating' piston at the end of the unit (centre), or in the case of most Bike shocks, in an external reservoir (right).
There is another type, which has the gas in a sealed 'bladder', fixed in the base of the body or remote reservoir (pic), or in a 'bag' which surrounds the cylinder assembly.
Edit; As WMF also pointed out, a shock can fail (lose all it's damping) without leaking at all.
Oil is made up of 'chain' molecules, it's what gives it it's 'thickness' (Viscosity).
When it's forced through the damping system (valves, tiny holes, etc) of a shock, the oil's 'chains' get broken down steadily, until it ends up much 'thinner', and no longer gives the amount of damping needed.
Gas struts for Suspension are Oil-damped, and as WMF pointed out, there is pressurised gas to control 'Aeration' or 'Emulsification' of the oil.
Cheaper gas shocks just have the gas mixed in with the oil, they're called the 'Emulsion' types. (Left in pic)
The best Shocks have the gas separated from the oil by another 'free-floating' piston at the end of the unit (centre), or in the case of most Bike shocks, in an external reservoir (right).
There is another type, which has the gas in a sealed 'bladder', fixed in the base of the body or remote reservoir (pic), or in a 'bag' which surrounds the cylinder assembly.
Edit; As WMF also pointed out, a shock can fail (lose all it's damping) without leaking at all.
Oil is made up of 'chain' molecules, it's what gives it it's 'thickness' (Viscosity).
When it's forced through the damping system (valves, tiny holes, etc) of a shock, the oil's 'chains' get broken down steadily, until it ends up much 'thinner', and no longer gives the amount of damping needed.
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