Those circular doodahs on the leaf spring of a 78 Spitfire 1500.

[Aristotle]

Chaps, currently car is up on axle stands awaiting a diff rebuild.

To make it a bit easier to to get the diff out I also removed the transverse leaf spring and at face value looks in good nick.

Now - - the leaf leaf spring was "Ahem" - allegedly a refurbed one some ten years ago although the car has done only about 300/400 miles per year since.

The circular doodahs I refer to are those little (plastic/rubber?) buttons which fit between the moving bearing surfaces of the leaves each side of the spring.

There is evidence of these doodahs still being there but seem a bit thin to me.

So my questions are do these things contribute much and should I wait (on the basis I've enough to do) till they completely wear out ?

If I do need to replace - I've seen there are some whizzy Delrin thick-uns which (reputedly) last ages and make the car ride higher - do I go for those or just a set of standard replacements ?

The car isn't going to be doing high mileages any time in my ownership, it's just for top down pootling summer time fun.

 

 

[Colin Lindsay]

For many years I drove Triumphs and never worried about the leaf spring buttons. Do they contribute? Well, they're supposed to stop wear, but if they're completely absent... I never noticed any noise nor excess wear without. I've replaced them in recent years on leaf spring refurbishments, but in the springs I refurbished before I just used loads of grease and wound putties round the spring leaves. As you say, there are thick ones plus the thinner 'original' types, but I didn't find any real difference in the Herald's stance after I used the thick ones on that spring last year.

[Mjit]

They do reduce noise a little bit, from the sping leaves sliding against each other - but so does a good squirt of spray Lithium grease between where the leaves touch every few years.
And they do reduce wear, caused by that leaf rubbing - but you'd probably need to drive 50,000+ miles to be able to see anything.
They also make reassembling your spring a royal PITA as they keep trying to escape and need to compress the spring a lot more to do up all the shackles - and that's with an original spring with the little recesses for the buttons.  Aftermarket replacement spring tend to be simple 'flat' strips of spring steel.

I did replace them when I overhauled my orginal spring 30 odd years ago - and found most of the rubber had crumbled and escaped after a couple of years.  I've since switched to an aftermarket replacement spring and run sans-buttons without issues.

Edited March 8 by Mjit

[Jon J 1250]

There are various alternative buttons available made out of Delrin, an Polyurethane in circular and top hat shapes.
I'm not 100% sure the originals were rubber as the ones in my original spring are like a hard black plastic and top hat shaped, though I can't say for sure they haven't hardened and been squashed into a top hat shape after 60 years in a leaf spring. (see photo)

As well as reducing wear and noise (they do wear a ring into the spring, see photo), I guess the original springs were designed so that the correct set and therefore ride height is achieved with the buttons fitted.

A problem I have seen others reports is the modern alternatives are too thick making the spring too curved, or making it hard to do the shackles up without straining the leaves, and giving high ride height and therefore too much positive camber when fitted.

I'm just in the process of rebuilding my rear suspension and currently plan to get some poly buttons, but will thin them down a bit where necessary.

Edited March 8 by Jon J 1250

[Aristotle]

Many thanks Chaps - - I am reassured - will leave well alone.

[ed.h]

Some pics here show what they look like on a GT6 (similar, maybe?)

http://bullfire.net/GT6/GT6-8/GT6-8.html

Ed