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rutthenut
29-08-2012, 11:26
Any suggestions on how best to stop my car squeaking like a family of mice are stuck in the suspension arms?

I've got the nylatron-type suspension bushes in the upper front wishbones, plus those in the rear wishbone/hub connections. Those in the front make a hell of a racket as the suspension moves, once it has warmed up. Spraying on WD40 or silicone lube spray doesn't achieve much other than making dirt stick to the outside.

If I do get to take off the wishbones at some time, what is the recommended solution to stop them from squeaking like a bunch of b*st*rds when reassembled?

strat24v
29-08-2012, 11:54
Fit some mos2(molydenum) modified nylatron bushes with stainless inserts. What you have are more than likely polyurethane. Easy to check, can you make a mark on the bush with your thumb nail? If so they are poly. The bent wishbone I got from Chris Richard had poly bushes. One problem with proper nylatron bushes are they are very hard, if the front upper wishbone bushes arent perfectly alligned, you wont get the bolt through, same with the rear wishbone, if you dont have perfect alignment you'll end up breaking something. The Nylatron doesnt give. Nylatron is a sort of brand name for Mos2 modified Nylon.

rutthenut
29-08-2012, 13:09
From what I recall, they were extremely tough and not something that a nail could make an impression on.
But I would've thought that if the bushes have molybdenum in them, that should be a lubricant so should be less likely to squeak? Will see what type they are though.

Don't want to get new bushes and inserts if the old ones are fine, as that would seem to be creating more work (and some expense) for myself. Also means I would need to know the specs in advance, or have the car on ramps for some time. Ok, it doesn't go out much, but that would mean not being able to take it out at all until replacements parts are ordered and fitted!

Spoken to someone and they did provide a hint that it *can* help for the wishbone bolt to only get tightened up when under load, with the wheels in their normal static position. Having said that, they have been on rather a long while, so might've expected them to find their natural base position with suspension travel. Any form of axial preload on the bushings would perhaps have been shifted since then. That is if I didn't tighten them with the car on the ground - I might well have done that in the first place, I can't remember that sort of detail now.

Thanks for comments though

strat24v
29-08-2012, 13:35
If they are Hawk parts, i think theyll be black polyurethane, mos2 nylon is mid to dark grey in colour if that helps.

May have a pic somewhere.

rutthenut
29-08-2012, 19:11
That's fine thanks - my bushes are indeed black plastic, of whatever form, so almost certainly not mos nylon. Still bl**dy tough to get in place though; I remember that much about them.
Do you have specs for mos nylon bushes and inserts that would fit the hawk upper wishbone, and a recommended supplier?

strat24v
29-08-2012, 19:34
Not saying Hawks bushes arent hard, think black poly is the hardest poly but Nylatron is hard(er) nylon, different again. No specs as such John. I just bought a length of solid bar and machined my own for various things.

try www.lamins.co.uk/ (http://www.lamins.co.uk/) they will have some stock, used to dealing with motorsport people and can supply.

Just checked the bush in Chris Richards old wishbone, definitely polyurethane, injection moulded and slightly deformable. Same applied pressure doesnt deform the same size nylatron bush.

I'd also check with Craig at ListerBell, his suspension bushes look a similar size and are definitely Nylatron, chance they may be interchangeable, worth a shot? Manufacturers tend to have their plastic bushes machined or moulded to suit the inner and outer metal bushes they use rather than the other way round.

Also, don't fit any type of poly or nylatron bush in the front end of the rear radius arms, besides rotational movement, the arm also transcribes an arc not in line with the pivot. If you did, you will end up with a snapped radius arm.

Marcolino
29-08-2012, 20:38
Or make the bushes with a lathe ...
I made some bushes a few years ago and bought the material at RS Components.

Also available in uk:

http://uk.rs-online.com/web/c/?sra=oss&searchTerm=nylatron&x=0&y=0

I cooled the material in the freezer and during machining with coolant spray.

rutthenut
30-08-2012, 09:59
If I had a lathe, and had used one at all in the last few decades since I left school, sounds like this would be a good option. If nylatron has built-in lubrication and even less flex, sounds better than tough black poly.

My rear tie bars have rose joints at both ends, but good warning for others who may look at upgrading bushes.

Thanks
J.R.

john
30-08-2012, 13:22
Aaah! But where is the squeak?
It's not necessarily in the poly or whatever the bushes are made of. The squeak is either between the bolt and the inner metal sleeve of the bush, or it's between the poly and the outer metal bush, (or the wishbone itself of course as there is probably no outer metal sleeve of the bush itself).
If it's the former then you have to withdraw the bolt and lubricate it with coppaslip or some such.
If it's the latter then red rubber grease (which is the same as no-crode for battery terminals) will keep it all quiet.
Of course using Nylatron is an even better idea.
No inner metal sleeve employed when these are made I assume?

rutthenut
30-08-2012, 14:56
They do have an inner metal sleeve, through which the pivot/mounting bolt is fitted. That bolt is tightened up through the whole assembly, so that the inner metal sleeves should be fixed and not rotate on the bolt at all (or else that through bolt will wear).

The bushes are of a top-hat design, with an inner sleeve and thick mounting washers on the outside, against the larger diameter of the bush. So the squeak will be between either the inner sleeve and the bush, the bush and the wishbone, or maybe between the bush and the end washers.

Doesn't sound metallic at all, so not expecting it to be the bolt and inner sleeves. Much worse in warm weather, once the car has been driven a way. Not something I plan to dismantle the front suspension to fix, but at some point I'll be changing the front springs/dampers and would take that opportunity to try and reduce/remove the squeaking.

Red rubber grease? I've always used vaseline on battery terminals!
Guess I should try and get some of that in the garage for whenever I work on such things.

Cheers,
John

john
30-08-2012, 16:36
AAh! Right, I'm getting this now. So the inner metal bush is free to rotate within the poly bush material.
I'm thinking Corse, and the Spax bushes fitted in the wishbones in which the inner and outer sleeves are bonded to the poly or rubber.

strat24v
31-08-2012, 12:19
With a spax bush, the inner and outer bushes are fixed tight and the rubber twists. With the poly and nylatron, the inner bush is clamped but the plastic is free to rotate. There should be a clearance of say half a n
Mil between the inner bush and the combined metal outer and poly/nylon top hat sections.