by Orlando St.R » Tue Dec 11, 2018 3:10 pm
I discovered, whilst having front wheel alignment undertaken on my car, that there was a fair amount of slop in the centre tie-rod end pins and bushes. The rubber that keeps the pin separate from the bush disintegrates. This allows the pin to move without that motion being transmitted along the centre tie rod. So, the right wheel on RHD cars moves in response to your steering input, but the left wheel doesn't; vice versa on LHD cars. This makes the steering feel vague and causes wandering. If you're trying to imagine what I'm talking about, see parts diagram below (which actually shows only the centre tie-rod and just one of the pin/bush assemblies installed in one tie-rod end. There are, of course, matching parts at the other end of the centre tie rod).
- tie rods etc.jpg (99.46 KiB) Viewed 1644 times
It's a bit of a faff getting the centre tie-rod off and, where the service manual reads 'tap the tie rod ball pins out of the steering arm and track rod end in which they are a taper fit', you will actually need a ball-joint separator.
Given that my standard tie-rod end pins and bushes had lasted only 6,000 miles, I decided to try the uprated version from SNGB, in which the rubber is replaced with PTFE:
https://www.sngbarratt.com/uk/#!/Englis ... c8db1911e0
- 133101U.png (55.24 KiB) Viewed 1644 times
I had the new parts pressed into the tie-rod ends by a local engineering shop. These then slide into the steering arms okay, although a fair bit of the shank of the pin is left visible because it doesn't seat quite perfectly in the taper. The silver lining in this apparent cloud is that it will be easier to get the ball-joint separator in there when the time comes for replacement.
- WP_20181029_19_57_25_Pro_2.jpg (545.72 KiB) Viewed 1644 times
The result is that the wandering is more-or-less eliminated. I don't think this design of steering will ever be as good as a rack and pinion set up, but the car no longer needs constant correction. I can't detect any downside to the uprated pin/bush design. If anything, it makes turn-in a little sharper, which I guess most people would welcome.
I discovered, whilst having front wheel alignment undertaken on my car, that there was a fair amount of slop in the centre tie-rod end pins and bushes. The rubber that keeps the pin separate from the bush disintegrates. This allows the pin to move without that motion being transmitted along the centre tie rod. So, the right wheel on RHD cars moves in response to your steering input, but the left wheel doesn't; vice versa on LHD cars. This makes the steering feel vague and causes wandering. If you're trying to imagine what I'm talking about, see parts diagram below (which actually shows only the centre tie-rod and just one of the pin/bush assemblies installed in one tie-rod end. There are, of course, matching parts at the other end of the centre tie rod).[attachment=2]tie rods etc.jpg[/attachment]
It's a bit of a faff getting the centre tie-rod off and, where the service manual reads 'tap the tie rod ball pins out of the steering arm and track rod end in which they are a taper fit', you will actually need a ball-joint separator.
Given that my standard tie-rod end pins and bushes had lasted only 6,000 miles, I decided to try the uprated version from SNGB, in which the rubber is replaced with PTFE: [url]https://www.sngbarratt.com/uk/#!/English/parts/fad0ba3d-395f-4470-9061-a3c8db1911e0[/url]
[attachment=1]133101U.png[/attachment]
I had the new parts pressed into the tie-rod ends by a local engineering shop. These then slide into the steering arms okay, although a fair bit of the shank of the pin is left visible because it doesn't seat quite perfectly in the taper. The silver lining in this apparent cloud is that it will be easier to get the ball-joint separator in there when the time comes for replacement.[attachment=0]WP_20181029_19_57_25_Pro_2.jpg[/attachment]
The result is that the wandering is more-or-less eliminated. I don't think this design of steering will ever be as good as a rack and pinion set up, but the car no longer needs constant correction. I can't detect any downside to the uprated pin/bush design. If anything, it makes turn-in a little sharper, which I guess most people would welcome.