Live axle rear radius arm bush

[andi4eyes]

Good morning, I like to tidy up my live axle a bit (wire wheel, paint) and replace bushes where needed.
Can someone tell me what the circled bushes are assuming they are not part of the radius arm assembly?

Cheers!

[7 wonders of the world]

you can get he bushes separately and press them out or upgrade to powerflex.

[Ivaan]

Redline will probably have these in stock. Just tell Chris you need a set of radius arm bushes for a LA and they'll be in the post. I changed mine last year. Used a local friendly garage with a big press.

[andi4eyes]

Thank you for your answers.

The bolt is under tension when the car is on jack stands. Is it enough to remove the bolt from the A-frame to release that tension from the spring?

[OldAndrewE]

Do you want to remove the axle to do the work or will you do it in situ?  

[paul richards]

Are your stands under the axle or chassis?

[andi4eyes]

I would do it in situ.

The jack stands are supporting the chassis. I have a floor jack to support the axle.

[OldAndrewE]

So you can remove the radius arms to do the bushes by removing the front nut and bolt and the rear nut. You should then be able to remove the radius arm from the bolt on the axle.  I would do one side at a time. 

[paul richards]

If you are not removing the axle I would suggest removing one radius arm at a time. i.e. remove and refurbish one radius arm, replace it and then remove the other for refurbishment. 

[andi4eyes]

Thank you for the suggestions on how to remove the radius arms. Will I be able to remove the entire bottom shock bolt (in order to get to the mounting point of the shock to remove rust and paint the area) when I disconnect the A-frame at the diff? Again assuming the chassis is supported on jack stands and the axle supported by floor jack.

[OldAndrewE]

Disconnecting the A-frame at the diff will make no difference.  I would leave that in place until you want to work in that area.  I would disconnect the top damper mount and then remove the lower bolt to remove the damper completely.  Do one side at a time and support that end of the axle on your floor jack

[Tazio]

And put some pipe lagging on the chassis rail under the axle to stop any unnecessary damage to the powdercoating.

[rkeywood]

Hi

Have the A frame bushes been replaced recently? If not I'd certainly be looking to do those at the same time and to ensure the axle is aligned and shimmed correctly. In that case I'd simply drop the axle onto the protected chassis rails and do the lot in one go. The existing doesn't look like it has the plastic washer/shims packing out the bushes which you might want to add (Caterham list as 'Nylon Racing Washer Shims') . The bushes and shims are still stock items at Caterham as well as Redline. As an aside, I personally wouldn't use Powerflex and in any case I don't think the 636 bush in the radius arm is available (I've machined the std PF99 in the past).

Robert

[andi4eyes]

Thank you for all the excellent tips.

I ended up lowering the spring platforms to release as much spring pressure from the bolt holding the radius arm and the damper.

Regarding the "Nylon Racing Washer Shims": I did include some of those in yesterday's Redline order. However I can't find them in my 90s assembly guide. Do they go either side of the radius arm bushes? Is there enough space?

 

[rkeywood]

Hi,

Use them on the bushes to take up the difference between the inner sleeve and the outer. They're 1mm thick and just fit what you can either side. The shortened 636 has been somewhat 'variable' in it's length in the past. Use them on the A frame chassis bushes as well and can be used on all the 636 bushes on the front suspension. 

R

[Iamscotticus]

OP, I would replace every bush you can while the section is apart.

Remember to do final tightening while the car is on the ground, or on a lift, at its riding stance.  This is because when tight, the bush center core sleeves are tightened between the brackets so the bonded centers resist movement while the outer rotates.  Tightening the links in their neutral position, not hanging, will ensure the bushes aren't being twisted100% of the time.

If you will PM me, we will exchange emails and I will scan and send you all the info I have on bush part numbers and locations.

I share the same views on not using bush compounds of polyurethanes or anything other than the soft rubber specified by Caterham, which predates back to Lotus.  Much cheaper to replace worn bushes than repair cracked chassis.  This includes avoiding the use of rose joints on Live Axle cars.  

On the subject,

Is there a OEM source for those live axle bushes?  From another BL car?

[rkeywood]

I think the shortened 636 and 2030 are bespoke to Caterham but all the others are parts bin bushes used on numerous cars (AH, MG, Ford, London Taxi...)  easily available as pattern parts from elsewhere BUT quality varies and, after spending the time to trace the OEM part no, the saving is usually pennies. The Y9 and Y16 are QH parts and the last time I looked you could save about 10p a bush buying elsewhere. Far better to buy from and support Redline or Caterham. In 30+ years I've never had a 'fall apart rubber' bush from Caterham but I have from elsewhere.