Leaf spring again.

[aggie]

When I stripped down the rear suspension on my Mk1 Spitfire I decided to buy a new leaf spring. I now regret that decision as, compared to the old one,  it looks and feels cheap and nasty.  So, I would like to renovate my old one  but having not done this before I don't really know how to begin.  Do I have to dismantle the spring completely to change the isolators ?  I guess that I really should in order to clean and repaint the leaves but, is it necessary.  Also I notice that, having removed the old rubber bushes at either end there is a steel sleeve which is too narrow to take the new Superpro polyurethane bushes.  The new spring does not have these sleeves and neither does it have any isolators.  Any info on the process would be gratefully received.  Thanks

[Pete Lewis]

thats the  remains of the metalastic bush is the outer sleeve   you need to remove it 

normally a slit with a hacksaw and they pop out easy 

new bush with have its own new adhered tube  to fit into a bare spring  ...the old tube is redundant 

Pete

 

[aggie]

Thanks Pete, that clears that bit up.

[johny]

This is a good point, what are the symptoms of wear in the rear spring apart from sitting low and shot end bushes? My Vitesse spring is the original and has had never had anything done to it apart from some paint a long time ago - admittedly its had an easy life so Ive just installed a 0.5" lowering block but should I worry about lubing/cleaning it or replacing said isolators?

[Pete Lewis]

all leaf springs are designed to run dry any   lube just attracts dust and then the debris grinds away at the surfaces 

old rusty and dusty is fine 

Pete

[Colin Lindsay]

So: does anyone make a good leaf spring these days? I have quite a number of old rusty and decrepit looking ones, no real way to tell what's worth refurbishing and what's scrap. I was going to treat the Herald to a new one, if worth doing.

GB Springs don't list for Herald.

 

[PeteH]

There are, or where, a couple of companies who would refurbish your old springs re tempered and rebuilt. One was in the Doncaster area and had good reports. Old fashioned “forgemasters” who knew their business.

Pete

[johny]

1 hour ago, Pete Lewis said:

all leaf springs are designed to run dry any   lube just attracts dust and then the debris grinds away at the surfaces 

old rusty and dusty is fine 

Pete

What do these isolators/pads/buttons do then? Cant be any left in my spring after 50+ years😭

[Pete Lewis]

well .........they reduce noise and act as a slipper pad after 50 years   its a look see but they can last a long time ...or when you have a poke and a look let us know   Ha !

Pete

 

[johny]

Do you know what sort of noise you can expect to get if theyre shot so I can listen out for it😁

[aggie]

C'mon guys give me some help.  I'm going to do it but I just need some guidance. I'm assuming that if I take out the shackle bolts and the centre bolt it all falls apart.  I know it seems simple but I don't want to bugger it up.  I need one of you Masterclasses Pete/Colin.

[Unkel Kunkel]

I have only dismantled a “ Swing Spring “ on a Mk 1V , however I understand the spring for a MK I is a six leaf thing which is even more basic:

This should come apart fairly easily apart from the bit Pete mentioned and advised about - removing the shackle bushes - the outer  part of the bush needs to be cut through and collapsed (hack saw) or pressed out (  takes some doing with a big G clamp or a proper press,

Only then will you be able to push in in your polyurethane bushes - so much easier.

As for “ button” / “ isolators” or what ever you call  them - they are usually miserably squashed useless flat things.Can replace like for like or upgrade to more modern material( there’s loads of discussion on this website and elsewhere on this topic).They can compensate for a degree of spring sag but conversely  can make the rear end of the car sit too high if the “ Buttons” are make too thick. Many “replacement”  springs omit them.

 The subject of whether to lubricate laminated springs probably goes back to the earliest “horseless carriages”!
Some advocate it.Some don’t - as per Pete’s comments.

There are compromises - “dry” lubricants such as graphite based stuff.

( The original Triumph service schedule for these cars does mention lubricating them)

Don’t assume that a replacement spring will be better simply because it is “new” and it therefore must  be better because it is replacing something “old” 

That ain’t necessarily so…

 

[Colin Lindsay]

15 hours ago, aggie said:

C'mon guys give me some help.  I'm going to do it but I just need some guidance. I'm assuming that if I take out the shackle bolts and the centre bolt it all falls apart.  I know it seems simple but I don't want to bugger it up.  I need one of you Masterclasses Pete/Colin.

Ok... you talked me into dismantling an old one yesterday afternoon. Crusty and rusty and all four shackle bolts broke (7/16 nuts). I'll find replacements and post the source.

 

Once these are removed nothing happens. It's the centre dowel holds it all together, the nut on the top is 5/8. The other end is a circular dowel head, not a bolt, so needs clamped - originally there's a slot in the top for a screwdriver so you can tighten the nut with a spanner whilst holding the dowel in place but if anyway rusty that's not how it'll release. I used plenty of oil and an impact wrench, and still had to lightly grip the bottom of the dowel which sits into the hole on top of the diff. Be careful not to distort or burr it. Once that's undone the pieces just expand slightly - no massive expansion as in a front spring - and then fall apart. I cleaned them up with wire wool, an old cloth and petrol.

  

The rubber buttons were flattened and distorted. New set off eBay, £30 for the uprated versions.

  

The end bushes have to be driven out; I use a large socket (1 1/8) in a vice with just a bolt pushed into the other end because my vice isn't big enough for two sockets; as the bolt pushes the bushes into the socket just remove it and shim out with nuts or washers. As usual the bush looks like it has come out, but it's only the rubber centre; the steel sleeve has remained behind. It needs driven out but a hammer and chisel works very well.

 

 

After that it's only a case or reassembly in the same order and as each leaf gets progressively smaller you can't mix them up. I'm going for polybushes this time, part of a set I used on the Herald so might as well try them.

Only thing holding me back now are the shackle bolts, but I'll source those now over a coffee, and the buttons, but it'll be reassembled in an hour at most. Hopefully this helps! 

[aggie]

Absolutely brilliant, just what I needed. Thanks,Colin.

BTW, did you get the photo of my Spitfire?

Alun.

[Colin Lindsay]

1 hour ago, aggie said:

Absolutely brilliant, just what I needed. Thanks,Colin.

BTW, did you get the photo of my Spitfire?

Alun.

Yes, still drooling over it.

[PeteH]

Went looking for some pic`s I took, when I worked on Mine (Swing Spring). But Colin beat us to it. So settled for a Piccy of the end result

Pete

[aggie]

Very nice too Pete. 

[Pdv]

Shackle bolts available from Paddocks.

Steve 

[Colin Lindsay]

2 hours ago, Pdv said:

Shackle bolts available from Paddocks.

Steve 

Slightly shorter shoulder than the originals, so the threads are against the shackle itself, not the shoulder. I've no idea how much difference it will make to the finished spring, but it's bound to be weaker than original. I'm still trying to find a source of longer bolts; might even have to go an inch longer so the shoulder clears the shackle, then cut the threaded section off once tightened.

 

 

[aggie]

Did you get them from JP ?

 

[alan.gilbert_6384]

On 13/11/2022 at 10:04, Colin Lindsay said:

Ok... you talked me into dismantling an old one yesterday afternoon. Crusty and rusty and all four shackle bolts broke (7/16 nuts). I'll find replacements and post the source.

 

Once these are removed nothing happens. It's the centre dowel holds it all together, the nut on the top is 5/8. The other end is a circular dowel head, not a bolt, so needs clamped - originally there's a slot in the top for a screwdriver so you can tighten the nut with a spanner whilst holding the dowel in place but if anyway rusty that's not how it'll release. I used plenty of oil and an impact wrench, and still had to lightly grip the bottom of the dowel which sits into the hole on top of the diff. Be careful not to distort or burr it. Once that's undone the pieces just expand slightly - no massive expansion as in a front spring - and then fall apart. I cleaned them up with wire wool, an old cloth and petrol.

  

The rubber buttons were flattened and distorted. New set off eBay, £30 for the uprated versions.

  

The end bushes have to be driven out; I use a large socket (1 1/8) in a vice with just a bolt pushed into the other end because my vice isn't big enough for two sockets; as the bolt pushes the bushes into the socket just remove it and shim out with nuts or washers. As usual the bush looks like it has come out, but it's only the rubber centre; the steel sleeve has remained behind. It needs driven out but a hammer and chisel works very well.

 

 

After that it's only a case or reassembly in the same order and as each leaf gets progressively smaller you can't mix them up. I'm going for polybushes this time, part of a set I used on the Herald so might as well try them.

Only thing holding me back now are the shackle bolts, but I'll source those now over a coffee, and the buttons, but it'll be reassembled in an hour at most. Hopefully this helps! 

Hi Colin, can I ask you, where did you get your replacement nylon buttons from ?

Thanks. 

[Colin Lindsay]

27 minutes ago, alan.gilbert_6384 said:

Hi Colin, can I ask you, where did you get your replacement nylon buttons from ?

Thanks. 

https://www.ebay.co.uk/itm/144504702564

[Colin Lindsay]

11 hours ago, aggie said:

Did you get them from JP ?

 

No, but going by the photo on the website, they're identical. The ones I'd prefer to get have a much longer collar and so a shorter threaded section. I'll keep enquiring.

  

 

 

[Clive]

11 hours ago, Colin Lindsay said:

Slightly shorter shoulder than the originals, so the threads are against the shackle itself, not the shoulder. I've no idea how much difference it will make to the finished spring, but it's bound to be weaker than original. I'm still trying to find a source of longer bolts; might even have to go an inch longer so the shoulder clears the shackle, then cut the threaded section off once tightened.

 

 

 

When I want 12.9 spec prop/diff bolts I had to use some longer ones and cut part of the thread off. Unless the bolt is application specific (so will likely be unavailble for anything Triumph these days) so the only option is chop chop.

[Colin Lindsay]

13 hours ago, clive said:

When I want 12.9 spec prop/diff bolts I had to use some longer ones and cut part of the thread off. Unless the bolt is application specific (so will likely be unavailble for anything Triumph these days) so the only option is chop chop.

The bolts I went for needed to be 1/4" diameter, 2" plain shank and about 1/2" threaded; the ones I bought online were quoted as 2 1/2" with the plain shank as 2 1/8". They actually aren't; they're 1 5/8 plain shank so I've notified the supplier and am awaiting a reply. 2 1/8" would be perfect.