Omega Owners Forum
Chat Area => General Car Chat => Topic started by: chrisgixer on 20 February 2014, 22:15:24
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Some of us have had issues with steering idlers failing early. On examination, the parts are fairly easy to separate. So the though occurs, could a poly sleave be manufactured and retro fitted..?
I'm guessing it would have to be a fairly hard shaw rating to allow a machined part to be pressed in, as opposed to a moulded part which would be tricky. Or trickier at least.
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Don't see why not.. Checked mine the other day. Absolutely solid at 159k. I don't know what everyone else does to them. ::)
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My gut feel is that you don't want any give at all.
Bronze bushes reamed to give a snug fit or needle rollers would be more appropriate in my opinion.
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Don't see why not.. Checked mine the other day. Absolutely solid at 159k. I don't know what everyone else does to them. ::)
You and me both ;D
Some of us have had issues with steering idlers failing early. On examination, the parts are fairly easy to separate. So the though occurs, could a poly sleave be manufactured and retro fitted..?
I'm guessing it would have to be a fairly hard shaw rating to allow a machined part to be pressed in, as opposed to a moulded part which would be tricky. Or trickier at least.
Had a thought on this... I vaguely recall 'Captain String' in the States separating his into three parts...
If the thickness of the sleeve is about a matchstick size, it should be possible to cast a new insert in situ :-\
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As always, its a compromise between comfort and accuracy. No rubber bushing, would mean very accurate steering, but transmit every single bump through the chassis rail and steering wheel.
Some shock absorption will be needed.
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Hmmm... :-\ I wonder about that... after all there's no such liner on the pitman arm as far as I'm aware :-\
Subjective question, was my car particularly harsh to drive :-\
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Hmmm... :-\ I wonder about that... after all there's no such liner on the pitman arm as far as I'm aware :-\
Subjective question, was my car particularly harsh to drive :-\
Two words.
Tyre pressures.
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As always, its a compromise between comfort and accuracy. No rubber bushing, would mean very accurate steering, but transmit every single bump through the chassis rail and steering wheel.
Some shock absorption will be needed.
I don't agree.
The steering idler is just mirroring the steering box on the other chassis rail. No give in that unit (or there shouldn't be).
The design of the power steering box is quite effective at preventing harshness reaching the steering wheel and there are already far too many sloppy linkages in the system :(
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Hmmm... :-\ I wonder about that... after all there's no such liner on the pitman arm as far as I'm aware :-\
Subjective question, was my car particularly harsh to drive :-\
Two words.
Tyre pressures.r
:P
They're lower than thery might have been ::) , but was referring to the suspension side of things...
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As always, its a compromise between comfort and accuracy. No rubber bushing, would mean very accurate steering, but transmit every single bump through the chassis rail and steering wheel.
Some shock absorption will be needed.
Considering how thin the bush is, 'some' is all you're currently getting. Removing compliance like this is a good way of breaking something else which isn't designed to take such loads. I've done this sort of thing with Capris: using poly bushes in the TCAs(wishbones on an Omega) and rack clamps means you wear out the internal bushes of the steering rack much quicker, and they're already a weak point. So you replace those with bronze, and find that the rubber coupling between the rack and the column starts to tear,. Hopefully, you notice this early because the column bush fails before you lose all steering! Replacing the coupling with a poly one makes for a nasty drive, and it's not unusual for the rack tube to split. I've even heard of one car with a cracked crossmember as a result of all this.
As we're talking about at least 10 year-old cars, with mileages around the 150k mark, having to replace an idler is just a normal wear and tear item, and should be good for the life of the car.
I think it would be more productive to replace the vertical rear bush with another front one, both acting in the same plane and axis. But that would require extensive re-engineering of the wishbone and subframe, neither of which are particularly practical, especially as it all works OK when fresh, it's just lacking in durability.
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Hmmm... :-\ I wonder about that... after all there's no such liner on the pitman arm as far as I'm aware :-\
Subjective question, was my car particularly harsh to drive :-\
Two words.
Tyre pressures.r
:P
They're lower than thery might have been ::) , but was referring to the suspension side of things...
Firm but with more travel. Some roll. Or more roll than mine anyway. But yours has self levelling.
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As always, its a compromise between comfort and accuracy. No rubber bushing, would mean very accurate steering, but transmit every single bump through the chassis rail and steering wheel.
Some shock absorption will be needed.
I don't agree.
The steering idler is just mirroring the steering box on the other chassis rail. No give in that unit (or there shouldn't be).
The design of the power steering box is quite effective at preventing harshness reaching the steering wheel and there are already far too many sloppy linkages in the system :(
There is also quit a large rubber damper between the steering box and column.
Trying to find my thread with pics of the idler in bits, but google seems restricted for some reason. :-\
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Apologies Nick, as I seem to have mudied the water somewhat :-[
The front of my car is completely polybushed, with the notable exception of the top mounts. The point I was trying to make, was that it doesn't make the car significantly harsh to drive...
Therefore, if the hard vinyl sleeve in the steering idler were replaced with the same substance I made my diff mounts from, it wouldn't make a noticeable difference to the feel of the steering. Especially as there is no such damping of the pitman arm :y
Hmmm... :-\ I wonder about that... after all there's no such liner on the pitman arm as far as I'm aware :-\
Subjective question, was my car particularly harsh to drive :-\
Two words.
Tyre pressures.r
:P
They're lower than thery might have been ::) , but was referring to the suspension side of things...
Firm but with more travel. Some roll. Or more roll than mine anyway. But yours has self levelling.
Exactly, see above for the reason behind the question :y
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As always, its a compromise between comfort and accuracy. No rubber bushing, would mean very accurate steering, but transmit every single bump through the chassis rail and steering wheel.
Some shock absorption will be needed.
Considering how thin the bush is, 'some' is all you're currently getting. Removing compliance like this is a good way of breaking something else which isn't designed to take such loads. I've done this sort of thing with Capris: using poly bushes in the TCAs(wishbones on an Omega) and rack clamps means you wear out the internal bushes of the steering rack much quicker, and they're already a weak point. So you replace those with bronze, and find that the rubber coupling between the rack and the column starts to tear,. Hopefully, you notice this early because the column bush fails before you lose all steering! Replacing the coupling with a poly one makes for a nasty drive, and it's not unusual for the rack tube to split. I've even heard of one car with a cracked crossmember as a result of all this.
As we're talking about at least 10 year-old cars, with mileages around the 150k mark, having to replace an idler is just a normal wear and tear item, and should be good for the life of the car.
I think it would be more productive to replace the vertical rear bush with another front one, both acting in the same plane and axis. But that would require extensive re-engineering of the wishbone and subframe, neither of which are particularly practical, especially as it all works OK when fresh, it's just lacking in durability.
The rubber is dimpled. So the dimples wear and give play. If poly, lubrication won't cause failure. I don't think its wise to stray too far from the original design.
It's purely a durability issue tbh.
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So a replacement sleave moulded in situ might be viable then :-\
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Apologies Nick, as I seem to have mudied the water somewhat :-[
The front of my car is completely polybushed, with the notable exception of the top mounts. The point I was trying to make, was that it doesn't make the car significantly harsh to drive...
Therefore, if the hard vinyl sleeve in the steering idler were replaced with the same substance I made my diff mounts from, it wouldn't make a noticeable difference to the feel of the steering. Especially as there is no such damping of the pitman arm :y
Hmmm... :-\ I wonder about that... after all there's no such liner on the pitman arm as far as I'm aware :-\
Subjective question, was my car particularly harsh to drive :-\
Two words.
Tyre pressures.r
:P
They're lower than thery might have been ::) , but was referring to the suspension side of things...
Firm but with more travel. Some roll. Or more roll than mine anyway. But yours has self levelling.
Exactly, see above for the reason behind the question :y
Front of mine is buggered ATM, so no point comparing there steering wise. Ride wise, as said.
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Do you have a spare idler which could be experimented with?
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As always, its a compromise between comfort and accuracy. No rubber bushing, would mean very accurate steering, but transmit every single bump through the chassis rail and steering wheel.
Some shock absorption will be needed.
I dissagree, there is no shock absorption via the pitman arm and steering box on the drivers side.
Rubber is only used as its cheap and easy. :y
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Slightly off topic but i'll probably get a answer quicker here :)
I've been under the front of mine and had a poke around.
I'm happy that all rubber bits are how they should be BUT they is quite a bit of slop in the steering while straight ahead.
Can this be adjusted in anyway at the ( I presume ) steering box ?
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With the engine off then that is correct with a re-circ ball steering box setup
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With the engine off then that is correct with a re-circ ball steering box setup
Okay, cheers Mark
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As always, its a compromise between comfort and accuracy. No rubber bushing, would mean very accurate steering, but transmit every single bump through the chassis rail and steering wheel.
Some shock absorption will be needed.
I dissagree, there is no shock absorption via the pitman arm and steering box on the drivers side.
Rubber is only used as its cheap and easy. :y
Not convinced, given the "flap" action on the idler, over bumps with the weight of the steering arm and the pas side road wheel gyroscopic inertia.
I'm thinking dead ahead/stearing stright, the slightest play and it will knock through the steering.
In corners I'd expect any play to be taken up. But dead ahead where there's no pressure on it the forces are purely vertical/up and down. Needle rollers aren't good in applications such as suspension and steering where the vast majority of the time is spent at or near normal ride height or, as in this case, steering dead ahead. As all the wear is consentated in one place on the bearing surface. Bit like top mount bearings. I've seen them pitted, as on bikes with rising rate rear suspension linkages. After 5000 miles, grab the rear tail unit and lift. There's guaranteed to be at least 5 mill of play. That's fine on a bike where most of the time the suspension is loaded. Unless your over the mountain at cadwell, then it knocks on landing.
But on a car where it's unloaded a good deal of the time, IMO, any play will resonate to the driver.
I'm thinking along the lines of a table tennis bat type material. If the right thickness and consistency can be found. Cut to length, roll into a tube, press the brass insert in....
Note to self, stop thinking aloud ;D
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I think what your missing is that yes, the passenger side might have any transmitted knock reduced thanks to the flex in the bush but, consider the drivers side, that has none removed.
So given that whats ok for the goose is good for the gander, I see no issue with changing from rubber on the idler as it can only get as bas as the already ok drivers side.
I can see a bush machined fom oil impregnated Nylon 7 working pretty dam well
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This is what I was thinking of...
http://www.ebay.com/itm/Black-Fast-Cast-Polyurethane-Liquid-Plastic-Casting-Resin-250g-230ml-litre-Kit-/281263962708?pt=UK_Crafts_Other_Crafts_EH&var=&hash=item417ca37a54
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All this trying to stiffen up the car only leads to one thing stress fractures,and cracked turrets.
i know the manta and the omega are different,so are escorts and mantas. My last two mantas had grA tarmac suspension, rose jointed arb. When i stopped driving it,and looked at probably, all turrets cracked,chassis rails cracking,and rear sills cracked.
should have seam welded it.
Omegas are 10+ years old,shells are tired and soft,go to stiff and fracture's will occur,unless you start seaming,and fitting a cage.
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I'd go with Nylon, I think.
Here's the original rubber innards. Note the dimples.
(http://i344.photobucket.com/albums/p326/chrisgixer/5C41C72E-5334-4A62-B7C7-9B1813C1DDD7-11353-00000BCD1A9083D3.jpg)
But I really don't see a big inanimate lump like a stearing box behaving like a spindly arm with a pivot under the same vibration. But I guess we'll see.
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Dimples only there to force an interference fit, whilst allowing large moulding tolerances :-\
Reassemble without the sleeve, suitably spaced with summat to give location, fill with resin mix, allow to set and trim excess as required :y
Unless the sleeve allows rotation of the arm/bush... :-\
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Surely 10 minutes on a lathe would be easier than moulding, and you could be sure that it's not off-centre then, too?
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But I really don't see a big inanimate lump like a stearing box behaving like a spindly arm with a pivot under the same vibration. But I guess we'll see.
Exactly, what I am saying is that the big inanimate lump that is the steering box is currently transmitting every vibration going from the drivers side through the chassis and setup and hence using an alternative material on the idler will make bog all difference. :y
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All this trying to stiffen up the car only leads to one thing stress fractures,and cracked turrets.
i know the manta and the omega are different,so are escorts and mantas. My last two mantas had grA tarmac suspension, rose jointed arb. When i stopped driving it,and looked at probably, all turrets cracked,chassis rails cracking,and rear sills cracked.
should have seam welded it.
Omegas are 10+ years old,shells are tired and soft,go to stiff and fracture's will occur,unless you start seaming,and fitting a cage.
In this case its not one of trying to stiffen things because a good quality new idler has pretty much no give in it, its more the fact we are trying to find an alternative which wont wear and fail nearly as quickly :y
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Dimples only there to force an interference fit, whilst allowing large moulding tolerances :-\
Reassemble without the sleeve, suitably spaced with summat to give location, fill with resin mix, allow to set and trim excess as required :y
Unless the sleeve allows rotation of the arm/bush... :-\
It does, hence the recommendation of oil impregnated nylon 7
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Surely 10 minutes on a lathe would be easier than moulding, and you could be sure that it's not off-centre then, too?
If you have a lathe... could space it evenly with matchsticks or similar :-\
Dimples only there to force an interference fit, whilst allowing large moulding tolerances :-\
Reassemble without the sleeve, suitably spaced with summat to give location, fill with resin mix, allow to set and trim excess as required :y
Unless the sleeve allows rotation of the arm/bush... :-\
It does, hence the recommendation of oil impregnated nylon 7
Got it :y
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But I really don't see a big inanimate lump like a stearing box behaving like a spindly arm with a pivot under the same vibration. But I guess we'll see.
Exactly, what I am saying is that the big inanimate lump that is the steering box is currently transmitting every vibration going from the drivers side through the chassis and setup and hence using an alternative material on the idler will make bog all difference. :y
....If there's no play. With play in a bearing in the idler, or something solid used instead of the rubber....
....it'll give an audible warning. :y ;D
The dimples shown allow some play to gradually creep in. The steering box, when loose, creaks. As we know, thanks to the pikey pensioner. The creak is totally insulted from the driver thanks to the riveted damper at the join of the column to box. Forget the name of it.
Anyway, I don't agree with you. :P ;D but let's see what transpires.
I need to get the old idler off and fit the new one first. Not this week anyway.
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At least it won't need a set up after... :y
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Fitted another new lemforder idler today, to a members car.
Had to tighten it to 110nm to get most of the play out of it. Correct torque being 60nm I believe.
There is still vertical play even now. :(
Cast arm is very different to the gm part. The number on the rubber bush is different between the two as well. Although I suppose they would be.
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Hmmm, has the Lemforder part changed? Or was it an ebay special, and a clone?
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Does anyone see a problem with making this in two halfs? Ie top and bottom top hats.
So it would be a case of inserting the top and bottom half, then inserting the inner sleeve, and then bolting it up as normal. Bit like the poly wishbone bush, but on a vertical plane obviously.
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Anyone?
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How thick would the material be? Installation might be an issue if too thin :-\
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Has anybody got an old idler arm and chassis mount?
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Has anybody got an old idler arm and chassis mount?
Yes 2. ...but oe one has very knackered rubber, partly missing, and pattern one might have odd dimensions.
Unfortunately these guys are very busy. :(
I rekon two halfs would work...? No?
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Inserting a poly sleeve without kinking/creasing it might be impossible as it will have limited structural strength until it's assembled :-\
That stuff I used for the diff mounts might work if the components can be positioned correctly and the resin can be poured/injected into the assembly...
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Inserting a poly sleeve without kinking/creasing it might be impossible as it will have limited structural strength until it's assembled :-\
That stuff I used for the diff mounts might work if the components can be positioned correctly and the resin can be poured/injected into the assembly...
Material will be Nylon, initially. Then if acceptable That oil impregnated Nylon 7 Mark mentioned.
It's quite hard, but does need to be a tight enough fit to avoid play, obviously.
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How thick are the walls of the sleeve?
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How thick are the walls of the sleeve?
1.5mm, going by the worn oe item here.
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...and it's bonded to the inner sleeve. Being rubber and all.
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You know if it's a part that could be turned down out of poly bar stock I'm more than happy to help..
Maybe once I've replaced mine I'll be able to visualise what parts actually do what on the idler ;D
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You know if it's a part that could be turned down out of poly bar stock I'm more than happy to help..
Maybe once I've replaced mine I'll be able to visualise what parts actually do what on the idler ;D
Hence my enquiry last week re the lathes. Is there a part seized? Or some issue currently?
The thickness of the wall may hinder machining, as the original
Part is moulded.
But lathe use would be handy. :)
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I reckon one lathe will run just fine with the motor bolted back on :y Might even get chance to do that this weekend.. really must get myself a mag base DTI so I can check the bed for true when it's screwed down, too.