What a difference a few Thou makes
wilkingj - 28/3/07 at 08:50 PM
I have just spent a couple of days in the shed.
After several discussions with Melvyn aka Rusty Nuts, I took then plunge and stripped the suspension bushes.
I have measured them and the crush tube, and ended up shaving about 35 thou off each side of the bushes.
Now I can do the bolts up nice and tight, and the suspension arms are silky smooth and can be moved with a single finger, rather than a handful of
fingers and a bulged bicep
.
Also no lateral play either.
Two of the bolts have been worn by the crush tube. OK only a little bit, but the bolts are NOT the "hinge" This should not be happening, and
I believe is an accident waiting for the future. Although the wear was minimal, I have only done 2300 miles in the car, and all in 10 months. I was
not happy with that.
I have poly bushes all round on my Land Rover, The Bolts on them have to be done up tight. They move on the crush tube, and the bolt is solid / tight
with the crush tube.
If you consider Metalastic bushes they have to be done up tight as well, although you have to get them into the right position before tightening, ie
they are preloaded. (Same as the leaf spring bushes on a Landy)
I firmly believe that the crush tube should be held tight and should not be allowed to rotate on the bolt. Thus preventing wear and damage to the
bolt.
Furthermore, if the bolt can vibrate and rotate, it will wear the mounting bracket hole into a larger hole or probably an oval, depending on where the
forces are directed.
This is what I have done. I believe that Rusty is right, and based on the way my polybushes are fitted to my Landrover, I have followed suit.
Personally I think the crushtubes should be a bit longer, so you dont need to make the bushes shorter to obtain the clearance.
Also fitted some Nice 260mm discs and calipers off a 4x4 Sierra.
Should have done this from the start, then I wouldnt have had that Brake ballance problem at the SVA.
Just got a few more jobs left to do now, like realign the alternator as its wearing the fanbelt out.
resite the headlight brackets so I can take the nosecone off with out having to remove the headlights first!
It'll keep me busy for a few days.
rusty nuts - 28/3/07 at 08:55 PM
Have you road tested it yet Geoff? Proof of the pudding
Andybarbet - 28/3/07 at 09:00 PM
I presume i should do this to mine before i fit them too ?
Sounds like a major improvement.
By the way, just looked in your archive Geoff, those ramps look great !
wilkingj - 28/3/07 at 09:07 PM
quote:
Originally posted by Andybarbet
I presume i should do this to mine before i fit them too ?
By the way, just looked in your archive Geoff, those ramps look great !
Been using the ramps for the last few days. Not convinced that are as good as I thought. However just used them with the car on the slope today. didnt
bother to level it up. Worked fine.
Used my 1ton chain block to hold the car securely whilst taking the suspension off and had the car supported on a large bit of wood spread across the
gap. (Small railway sleeper type of thing!)
Assemble one or two joints, and do the bolts up tight and see if the arm is stiff or not.
As Chris says... its suck it an see.
Once I get the sizes sorted, it got easier!! I took about 35 thou off the outside of each bush. but only after checking how tight it was when bolted
up tight. ie if it aint broke, dont fix it
wilkingj - 28/3/07 at 09:11 PM
quote:
Originally posted by rusty nuts
Have you road tested it yet Geoff? Proof of the pudding
Yes, but not far.. only round the block when testing the new brakes. It seems a lot lighter on the steering / front end. I cant see why, as its not
the turning part of the front end that has been altered.
I need to get it out for a good run.
Also I want to recheck all the camber angles etc now its been on the road a while. ie its settled down a bit.
kenton - 28/3/07 at 09:32 PM
Rather than reducing the size of the bushes i added an m12 dowty washer (very thin) on the end of the insert. Its a perfect fit thus enabling the bolt
to be fully tightened.
Cubby - 29/3/07 at 01:24 PM
By how much do the crush tubes extend from the polybush now ?
wilkingj - 29/3/07 at 05:49 PM
quote:
Originally posted by kenton
Rather than reducing the size of the bushes i added an m12 dowty washer (very thin) on the end of the insert. Its a perfect fit thus enabling the bolt
to be fully tightened.
Thats a good idea... WTF is a Dowty washer?
I dont have any of those washers, but I do have a lathe. So I opted to turn the bushes down.
I suppose it depends on how long your crush tubes are. Mine are all 41.8mm
So I turned the bushes down to give an overall size when fitted in the arms of about 41.3mm ish!. The original width of the bushes in the arm was
42+mm on every one. Its just a lot of measuring and some simple maths.
There is very little protusion of the crush tube, you can barely feel it. but its enough to take the pressure off the poly bush.
When pulled up that are a nice fit, and with no binding.
It was a lot of suck it and see, and several attempts until I got it right. ie small slices taken off and then trial fit, then try again!!!
Like Chris says... manufacturing tolerances etc. Although my bushes were fairly consistent.
Paul (Notts) - 29/3/07 at 06:33 PM
Was planning to drill out some m10 washers but if these dowty m12 fit -where can I get some!!!!!
Paul.
rusty nuts - 29/3/07 at 07:37 PM
When I did mine Geoff I didn't bother refitting the arm each time I just nipped the crush tube in a vice and tested rotation. A lot easier than
refitting.
Danozeman - 29/3/07 at 08:43 PM
I did this on mine too. Its made the suspension hell of a lot better..
wilkingj - 29/3/07 at 09:46 PM
quote:
Originally posted by rusty nuts
When I did mine Geoff I didn't bother refitting the arm each time I just nipped the crush tube in a vice and tested rotation. A lot easier than
refitting.
DOH!!!! Why didnt I think of that! Bit late now, done three of the four corners.
kenton - 29/3/07 at 10:59 PM
Dowty washers are used on hydraulic fittings that do not have a taper fit to stop leaks.
They have a moulded bit of rubber on the inside edge (trims off in seconds with a stanly knife.)
They are exactly the right size!
Got mine from local tractor dealer, have a works account so as many fixings, paint,fuel hose etc as poss come this way.
Even managed to get a shotblast cabinet that so far only i have used!
kenton
kenton - 29/3/07 at 11:17 PM
Here they are
http://www.workshopsupplies.co.uk/en-gb/dept_701.html
kenton