Front Lower Wishbone Clunk
#1
Front Lower Wishbone Clunk
A while back I mentioned a clunk I'd been hearing from the front of the car. Today, I took her in to get an oil change and new oil filter (technically, changing the oil is easy. But dealing with the used oil, and especially actually getting access, is a hassle), and took the opportunity to ask my mechanic about a few issues I'd been having. Especially the clunk.
Turned out to be the lower wishbone fulcrum. The bush appears pretty old, so will need replacing.
The mechanic suggests we replace the entire fulcrum rod. Parts 2 to 7 on the diagram. Would the rod itself need replacing? It seems to be a pretty hefty bit of kit. There also only appears to be one bush, #3, which doesn't seem right. Wouldn't you need two per side?
Parts 2 to 7. Especially #3
These are pics I snapped with my tablet while the car was on the lift.
The end facing the front of the car.
The end towards the rear.
I gather it's quite the procedure to replace these, involving removing the steering rack and compressing the springs. My mechanic reckons he can borrow a special device from his mate at the Jaguar dealership in town for the springs. But anyway, these need to be done right if done at all. With OEM metalastic bushes, I gather. No play in the joint at this stage, but the noise is getting gradually worse. It won't last forever.
Anyway, as usual, I come humbly seeking advice and guidance from the wise masters....
PS: What is this round plug, and why is it apparently leaking? And what can I do about it?
It's not a major leak, but the plug is a bit loose. Rotates reasonably freely.
Turned out to be the lower wishbone fulcrum. The bush appears pretty old, so will need replacing.
The mechanic suggests we replace the entire fulcrum rod. Parts 2 to 7 on the diagram. Would the rod itself need replacing? It seems to be a pretty hefty bit of kit. There also only appears to be one bush, #3, which doesn't seem right. Wouldn't you need two per side?
Parts 2 to 7. Especially #3
These are pics I snapped with my tablet while the car was on the lift.
The end facing the front of the car.
The end towards the rear.
I gather it's quite the procedure to replace these, involving removing the steering rack and compressing the springs. My mechanic reckons he can borrow a special device from his mate at the Jaguar dealership in town for the springs. But anyway, these need to be done right if done at all. With OEM metalastic bushes, I gather. No play in the joint at this stage, but the noise is getting gradually worse. It won't last forever.
Anyway, as usual, I come humbly seeking advice and guidance from the wise masters....
PS: What is this round plug, and why is it apparently leaking? And what can I do about it?
It's not a major leak, but the plug is a bit loose. Rotates reasonably freely.
#2
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Two bushes per side, yes. The only shows one for purposes of visual clarity, I suspect
The shaft (#2) can be reused....IF it isn't damaged on removal. In some cases the shaft is seized in place and brutality is needed to remove it.
How was it determined that the bushes are causing the clunk? It's certainly possible, of course. But, deterioration at the outer edges doesn't positively condemn the bushings.
Cheers
DD
The shaft (#2) can be reused....IF it isn't damaged on removal. In some cases the shaft is seized in place and brutality is needed to remove it.
How was it determined that the bushes are causing the clunk? It's certainly possible, of course. But, deterioration at the outer edges doesn't positively condemn the bushings.
Cheers
DD
The following 2 users liked this post by Doug:
Greg in France (04-22-2019),
Some Day, Some Day (04-22-2019)
#3
Agree with Dug, but age is against them now, sadly.
BIG job, the rack, yes, and the engine is in the way to clear them all the way out. Support the engine, lower the cradle, BASH those pins out.
New pins are NOT expensive.
Greg in France has done this recently, and has it listed here in the archives, or PM him, no issues.
That rubber plug is timing chain tensoioner ratchet access hole, and they leak with age, again. New plug (RTV coated) and carry on, OR, the newer one piece alloy style that Warjon uses is another option.
BIG job, the rack, yes, and the engine is in the way to clear them all the way out. Support the engine, lower the cradle, BASH those pins out.
New pins are NOT expensive.
Greg in France has done this recently, and has it listed here in the archives, or PM him, no issues.
That rubber plug is timing chain tensoioner ratchet access hole, and they leak with age, again. New plug (RTV coated) and carry on, OR, the newer one piece alloy style that Warjon uses is another option.
The following 2 users liked this post by Grant Francis:
Greg in France (04-22-2019),
Some Day, Some Day (04-22-2019)
#4
SDSD, Like Grant and Doug, I very much doubt that the lower fulcrum bushes are producing the clonk. I would ask your mechanic to check the following:
- Anti roll bar rubber bushes inside the bracket fixings to the chassis rails, or antiroll bar drop link bushes connecting it to the lower wishbone
- Front stub axle bearing race wearing grooves in the actual stub axle
- Front axle bearings too loosely adjusted
- Top wishbone bushes (easy to do)
- Lower shock absorber bolts not tight enough
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Grant Francis (04-22-2019)
#5
I agree with Greg about checking other possibilities before replacing the lower bushes
Just to add to what Greg said.
Shock absorber upper bushes are very soft and deteriorate, these will also cause a clunk.
If you do replace the lower bushes, make sure the mechanic does it by the book. The bushes are locked onto the shaft and do not rotate.
When new ones are installed full weight MUST be on the front suspension before tightening the fulcrum shafts or the bushes will fail.
Installing new bushes into the LCA is made easier with soapy water.
Just to add to what Greg said.
Shock absorber upper bushes are very soft and deteriorate, these will also cause a clunk.
If you do replace the lower bushes, make sure the mechanic does it by the book. The bushes are locked onto the shaft and do not rotate.
When new ones are installed full weight MUST be on the front suspension before tightening the fulcrum shafts or the bushes will fail.
Installing new bushes into the LCA is made easier with soapy water.
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Grant Francis (04-22-2019)
#6
Thanks everyone for all your advice, suggestions, and warnings. Much appreciated.
To narrow down the source, we had the car on a lift, the sort that lifts by the wheels rather than with supporting bars under the chassis. So the car was sitting normally, all weight on its wheels. Getting under the car, he pulled on the anti-sway bar to get the car rocking up and down, producing the clunk. Listening under the car to see where the clunk was coming from, he (and I, sort of helping) could place our fingers against the head of the fulcrum shaft #2 and feel a slight movement, like it was jerking around a fraction, and feel the vibration of each clack.
It is possible, I imagine, that a clack in another part of the general area would also vibrate down in the lower wishbone, so certainly some vibrations are transmitted, but I could also feel what seemed to be some torsional movement as the car clunked up and down.
At any rate, the parts at least don't appear to be expensive. And good point about the old pins getting damaged in removal. They're cheap enough. But first it wouldn't hurt to try to eliminate the list of alternatives Greg's offered. I'll try to find out where those are, and then translate them into Japanese....
To narrow down the source, we had the car on a lift, the sort that lifts by the wheels rather than with supporting bars under the chassis. So the car was sitting normally, all weight on its wheels. Getting under the car, he pulled on the anti-sway bar to get the car rocking up and down, producing the clunk. Listening under the car to see where the clunk was coming from, he (and I, sort of helping) could place our fingers against the head of the fulcrum shaft #2 and feel a slight movement, like it was jerking around a fraction, and feel the vibration of each clack.
It is possible, I imagine, that a clack in another part of the general area would also vibrate down in the lower wishbone, so certainly some vibrations are transmitted, but I could also feel what seemed to be some torsional movement as the car clunked up and down.
At any rate, the parts at least don't appear to be expensive. And good point about the old pins getting damaged in removal. They're cheap enough. But first it wouldn't hurt to try to eliminate the list of alternatives Greg's offered. I'll try to find out where those are, and then translate them into Japanese....
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Grant Francis (04-22-2019)
#7
Anti roll bar numbers 18 to 25:
Stub axle grooved and bearing loose tightness of 10 grooves in 3 (though from what you said in your last post sounds unlikely)
Top wishbone bushes 4, 5, 6, 7:
My favourite from your last post is the anti-roll bar fixings and rubbers, so I would get the guy to look at them first. Note that the ARB bracket bolts need a spanner on the top and the bottom, no captive nuts. The top hexagon of the nut and bolt (17 and 21) can only be reached (engine in car!) from above with a long extension on the socket. You remove the airbox and looking down you can just see and get on the bolt top, while someone else undoes the bottom from underneath.
Stub axle grooved and bearing loose tightness of 10 grooves in 3 (though from what you said in your last post sounds unlikely)
Top wishbone bushes 4, 5, 6, 7:
My favourite from your last post is the anti-roll bar fixings and rubbers, so I would get the guy to look at them first. Note that the ARB bracket bolts need a spanner on the top and the bottom, no captive nuts. The top hexagon of the nut and bolt (17 and 21) can only be reached (engine in car!) from above with a long extension on the socket. You remove the airbox and looking down you can just see and get on the bolt top, while someone else undoes the bottom from underneath.
Last edited by Greg in France; 04-23-2019 at 02:41 AM.
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Some Day, Some Day (04-23-2019)
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#8
Thanks very much Greg. Very helpful indeed. I'll print those out with some Japanese translations, and see what my mechanic thinks. The ARB did seem to change direction (rotate a bit inwards) as the car was pulled down. I assume that's normal, or perhaps I was imagining it.
Though first priority is the chewed high-tension coil lead. Though I don't want to buy a whole new set--I'm sure a single one of a suitable shape can be found. Time for some hunting....
Though first priority is the chewed high-tension coil lead. Though I don't want to buy a whole new set--I'm sure a single one of a suitable shape can be found. Time for some hunting....
#9
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#10
Hmmm. Not many speed bumps in Japan (anywhere), but it does clack when going over ramp lips in parking buildings. When the front is temporarily unweighted, then weighted again. The clack isn't really loud enough to be heard with the windows up, for what it's worth.
Out of curiosity, I went out to the car, wiggled under the front bumper, and pushed up on the bumper (figuring it's bolted on there very strongly) to bounce the car as vigorously as I could (making sure that I had enough room that the descending car wouldn't crush me or the number plate slash my throat) and while there was an initial clack or two, I couldn't get the regular clacks we got in the garage using the ARB to pull on. Was that simply as I wasn't moving the car as much as I thought, or could it actually be the ARB? I rather hope it is, though with my luck with this car, it's usually the harder, more expensive thing at fault....
Out of curiosity, I went out to the car, wiggled under the front bumper, and pushed up on the bumper (figuring it's bolted on there very strongly) to bounce the car as vigorously as I could (making sure that I had enough room that the descending car wouldn't crush me or the number plate slash my throat) and while there was an initial clack or two, I couldn't get the regular clacks we got in the garage using the ARB to pull on. Was that simply as I wasn't moving the car as much as I thought, or could it actually be the ARB? I rather hope it is, though with my luck with this car, it's usually the harder, more expensive thing at fault....
#11
#12
One additional question, if I may. Would it be an idea to get both sides done, assuming it's the wishbones?
I'm thinking if it's the hard-to-access lower wishbone, which requires dropping the steering assembly, that would probably make access on both sides easier so on the assumption that the rubber is equally old, get 'em both done and be done with it.
On checking from the bill from when I had that huge overhaul done, the wishbones weren't touched.
I'm thinking if it's the hard-to-access lower wishbone, which requires dropping the steering assembly, that would probably make access on both sides easier so on the assumption that the rubber is equally old, get 'em both done and be done with it.
On checking from the bill from when I had that huge overhaul done, the wishbones weren't touched.
#13
Hi Someday
With that amount of work involved, it would certainly pay in more ways than one to have them both done at once, together with the drop links on the Anti Roll Bar as well as the Shock Absorber Bushes
As on my last two MOT's the Tester completely failed to see that the Shock Absorber Bushes were worn out, which made a very loud Clonking Noise under the Car when going over Manhole Covers or Speed Bumps
This was mega annoying, as it took me forever to track down the Cause of this noise but when I eventually found it, I decided that I would make my own Shock Absorber Bushes and Fit them myself
Which was 'easy peasy lemon squeezy' and best of all you can tune the ride to Hard or Soft or Something in between, depending on the Hardness of the Rubber that you use and I've even cut some from a Nylon Chopping Board and they worked Great
Really, Really, dead easy to do all you need is a drill with a Cheap and Cheerful Hole-saw Cutter
I only came unstuck once when the Previous Owner used the Strongest Loctite on the Shock Absorber Nuts but that usually doesn't happen and it usually doesn't take three days to try and undo those Nuts
More often than not you can easily do it in one hour per side or even less
Here is the Link Below: which includes the Shock Absorber Saga of the Day it all went Wrong! when the Previous Owner used Grade 'A' Loctite on the Nuts which really drove me, er...Nuts! trying to undo them
What was he Thinking!
Making and fitting my own Shock Absorber Bushes to Fix a Clonking Sound under the Car
With that amount of work involved, it would certainly pay in more ways than one to have them both done at once, together with the drop links on the Anti Roll Bar as well as the Shock Absorber Bushes
As on my last two MOT's the Tester completely failed to see that the Shock Absorber Bushes were worn out, which made a very loud Clonking Noise under the Car when going over Manhole Covers or Speed Bumps
This was mega annoying, as it took me forever to track down the Cause of this noise but when I eventually found it, I decided that I would make my own Shock Absorber Bushes and Fit them myself
Which was 'easy peasy lemon squeezy' and best of all you can tune the ride to Hard or Soft or Something in between, depending on the Hardness of the Rubber that you use and I've even cut some from a Nylon Chopping Board and they worked Great
Really, Really, dead easy to do all you need is a drill with a Cheap and Cheerful Hole-saw Cutter
I only came unstuck once when the Previous Owner used the Strongest Loctite on the Shock Absorber Nuts but that usually doesn't happen and it usually doesn't take three days to try and undo those Nuts
More often than not you can easily do it in one hour per side or even less
Here is the Link Below: which includes the Shock Absorber Saga of the Day it all went Wrong! when the Previous Owner used Grade 'A' Loctite on the Nuts which really drove me, er...Nuts! trying to undo them
What was he Thinking!
Making and fitting my own Shock Absorber Bushes to Fix a Clonking Sound under the Car
The following 2 users liked this post by orangeblossom:
Greg in France (04-24-2019),
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#14
Thanks. I've taken a look at your home-made fix, OB. I know the top bushes are new-ish, replaced in 2016, and don't make a noise (the noise is very definitely from the bottom part of the engine bay), though I don't know when the underside bushes at the top of the shock absorber were changed. When you lowered the shock absorber, that wasn't by hand, was it?
I need to get the clunk source alternatives eliminated, but if it does prove to be the lower wishbone, I might get the upper wishbone and anti-roll bar ones done anyway. Parts seem cheap. And the extra work wouldn't be that much compared to the lower wishbone fulcrum, I gather. I thought all the rubber the car rides on had been replaced when I got that major overhaul done, but apparently not. This is the only rubber-related stuff I can find that they did:
I need to get the clunk source alternatives eliminated, but if it does prove to be the lower wishbone, I might get the upper wishbone and anti-roll bar ones done anyway. Parts seem cheap. And the extra work wouldn't be that much compared to the lower wishbone fulcrum, I gather. I thought all the rubber the car rides on had been replaced when I got that major overhaul done, but apparently not. This is the only rubber-related stuff I can find that they did:
Front member mounts shot --> Replaced. 30,000 yen
Engine mounts --> Replaced
Tie rod end boots --> Replaced
Power steering bushes --> Replaced
Engine mounts --> Replaced
Tie rod end boots --> Replaced
Power steering bushes --> Replaced
#15
One additional question, if I may. Would it be an idea to get both sides done, assuming it's the wishbones?
I'm thinking if it's the hard-to-access lower wishbone, which requires dropping the steering assembly, that would probably make access on both sides easier so on the assumption that the rubber is equally old, get 'em both done and be done with it.
On checking from the bill from when I had that huge overhaul done, the wishbones weren't touched.
I'm thinking if it's the hard-to-access lower wishbone, which requires dropping the steering assembly, that would probably make access on both sides easier so on the assumption that the rubber is equally old, get 'em both done and be done with it.
On checking from the bill from when I had that huge overhaul done, the wishbones weren't touched.
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Some Day, Some Day (04-24-2019)
#16
Thanks as always, Greg.
Step 1: Confirm location of clunk by eliminating easier-to-access alternatives given above.
Step 2: Order two sets of everything that goes in the wishbone.
Step 3: Feel vaguely like a fraud as I pay others to do that which I am too incompetent to do myself. This one seems like it wouldn't be easy even for an experienced wrencher, at least.
Step 4: Enjoy smooth, clunk-free driving. Until the next thing goes wrong....
Step 1: Confirm location of clunk by eliminating easier-to-access alternatives given above.
Step 2: Order two sets of everything that goes in the wishbone.
Step 3: Feel vaguely like a fraud as I pay others to do that which I am too incompetent to do myself. This one seems like it wouldn't be easy even for an experienced wrencher, at least.
Step 4: Enjoy smooth, clunk-free driving. Until the next thing goes wrong....
#17
Hi Someday
Replacing the Shock Absorber Bushes is easy! including the ones on the underside of the Wing/Fender and easier still if you take the road Wheel off first
Once you undo the Top Nuts which are either 2 Nuts locked together or sometimes just a Nylock, then that's the worst part over as long as you have your New Shock Absorber Rubber bushes placed within easy reach
Just use Two Hands to pull the Shock Absorber down and then hold it down with one hand while you put the underneath Shock Absorber Rubber Bushes on
Then guide the threaded Spigot of the Top of the Shock Absorber through the hole in the Wing/Fender as you Carefully let it expand, then do the ones on Top and replace the Lock Nut
Worn Top Shock Absorber Bushes and by 'Top' I'm also including the ones that go under the Wing/Fender, can make a noise like someones is sawing your Car in half with a hacksaw
Or a very definite 'Thump' which sound like the noise of a loose Exhaust Pipe banging against the underside of your Car
Maybe quite unusually for an XJS, there is no 'Point of no return' where you wish you hadn't started as once you undo the Locknuts which are easily accessible from under the Bonnet/Hood
Doing this job is really a 'Walk in the Park'
And as I say if you make your own, rather than using 'Stock' then you can very easy 'Tune your ride' to either Hard or Soft, or something in between, which can make an Amazing difference in the Handling of your Car
Just before I did mine, 'Cherry' was rolling around like a drunken Sailor but after I fitted my Home Made Shock Absorber Bushes, She Corners like a 'Lotus' dead flat like She is on rails
Replacing the Shock Absorber Bushes is easy! including the ones on the underside of the Wing/Fender and easier still if you take the road Wheel off first
Once you undo the Top Nuts which are either 2 Nuts locked together or sometimes just a Nylock, then that's the worst part over as long as you have your New Shock Absorber Rubber bushes placed within easy reach
Just use Two Hands to pull the Shock Absorber down and then hold it down with one hand while you put the underneath Shock Absorber Rubber Bushes on
Then guide the threaded Spigot of the Top of the Shock Absorber through the hole in the Wing/Fender as you Carefully let it expand, then do the ones on Top and replace the Lock Nut
Worn Top Shock Absorber Bushes and by 'Top' I'm also including the ones that go under the Wing/Fender, can make a noise like someones is sawing your Car in half with a hacksaw
Or a very definite 'Thump' which sound like the noise of a loose Exhaust Pipe banging against the underside of your Car
Maybe quite unusually for an XJS, there is no 'Point of no return' where you wish you hadn't started as once you undo the Locknuts which are easily accessible from under the Bonnet/Hood
Doing this job is really a 'Walk in the Park'
And as I say if you make your own, rather than using 'Stock' then you can very easy 'Tune your ride' to either Hard or Soft, or something in between, which can make an Amazing difference in the Handling of your Car
Just before I did mine, 'Cherry' was rolling around like a drunken Sailor but after I fitted my Home Made Shock Absorber Bushes, She Corners like a 'Lotus' dead flat like She is on rails
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Some Day, Some Day (04-24-2019)
#18
A walk in the park you say, OB? Well, there are walks and there are parks....
Lady Mary corners very well--the limiting factor is usually my fat **** trying to slide off the seat. I wouldn't mind sacrificing a bit of that for a softer ride, however. I don't know what sort the seller put on when he replaced them prior to delivery. Harder than OEM? Softer? Actual OEM? Your instructions seem clear and easy to follow, so it's definitely something to consider. I should take a wheel off and see what the under-top ones are like. And see how easy the nuts are to undo on both sides before I commit myself--your experience seems pretty hellish.
Lady Mary corners very well--the limiting factor is usually my fat **** trying to slide off the seat. I wouldn't mind sacrificing a bit of that for a softer ride, however. I don't know what sort the seller put on when he replaced them prior to delivery. Harder than OEM? Softer? Actual OEM? Your instructions seem clear and easy to follow, so it's definitely something to consider. I should take a wheel off and see what the under-top ones are like. And see how easy the nuts are to undo on both sides before I commit myself--your experience seems pretty hellish.
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orangeblossom (04-24-2019)
#19
Hi Someday
I just got unlucky when the P.O. used Loctite on the Locknuts, (which doesn't usually happen)
More often than not doing this Job is unbelievably easy and very Satisfying and I've even changed these Bushes multiple times in one day, in my ongoing quest for the perfect ride!
They make more of a difference than you would ever think!
I just got unlucky when the P.O. used Loctite on the Locknuts, (which doesn't usually happen)
More often than not doing this Job is unbelievably easy and very Satisfying and I've even changed these Bushes multiple times in one day, in my ongoing quest for the perfect ride!
They make more of a difference than you would ever think!
#20