Aprilia steering joints

[davidwheeler]

I fitted new Silentbloc bushes to the steering but those on the ends of the drag link have both failed in 1000 miles or so. The track rod ends seem OK so far. The one on the end of the steering box arm I have replaced with a nylon bush gripped in the drag link end and sliding on the inner of the old bush.  It seems to have sufficient compliance but I have no idea how long it will last.  I have ordered new bushes from Omicron but the whole concept seems dodgy to me even though it was also used on the Aurelia.  Has anybody come up with a better solution?  Some sort of spherical bearing would seem to be ideal.
David

[ncundy]

Funnily enough my father was discussing this at he weekend. Not that long ago he replaced the Silentbloc bushes with normal ball joints on his Aurelia. But the ball joints have worn rather quickly (and leave a small vibration through the steering) so he is going back to the Silent blocks, although he has some thoughts on it. He is hoping to get to the AGM on the Sunday, so if you are around I can point him out

[JohnMillham]

Very interesting! Augusta owners have long been having a discussion about Silentbloc bushes, as Karl Sänger in Switzerland is of the opinion that the "pins" should be just free enough to turn in the bush. He greases his each year or so and says they don't wear noticably. The rubber doesn't wear out as it's no longer twisted. I doubt very much that this is the way Lancia intended the bushes to be used, but I have been trying this method for the past few months on my Augusta with no noticable ill effects so far. The trouble is, I suspect that modern Silentbloc bushes have a harder rubber in them than the original ones, so it's more likely to "tear" when the pins are tight. I worked out the angles the steering joints have to attain, and it's considerably more than recommended for modern bushes. The angles would probably be very similar on Aprilias, so perhaps you might try the "Sänger method" and keep the pins lubricated but very slightly loose, so they can turn in the bushes.  Let us know how you get on.
 Regards, John

[davidwheeler]

Most interesting!  I must confess I am a little alarmed at the thought of using the pin in the bush as a bearing but it is worth a try I guess, with plenty of rubber grease it should not come to much harm.  This means trusting to the split pin in the nut of course!  I may just see how the experimental nylon bush works, it runs on the old centre tube of the Silentbloc bush which is nice and shiny.  Failing that, I shall try the Sanger fix.  I shall not be at the A.G.M. its a bit costly for a pensioner!