35 replies to this topic

[Mangham54]

Hey guys,

Sorry for yet another thread about my bloody brakes... but here goes:

I have just been preparing the car ready for my new handbrake cable and noticed that there is some play in the offending Caliper on it's lower slider. However when I undid the upper bolt I noticed that I could slide the whole caliper straight of the lower one. Additionally as it came out a small piece of white plastic fell out!!! Without this piece of plastic the amount of free play on the caliper just gets worse.

I have now had a look at the EliseParts website and noticed the rear caliper servicing kit they do... http://www.elisepart...urbishment-kit/ and clearly there is no little piece of white plastic like this:




or as you can see on this pic:




.

Now Having had to undo the retaining bolt on the lower slider with a pair of pliers (as the bolt head had previously been chewed before I had got the car it turns out) I need a new one anyway. AutoVaux or Loti I presume.

But my big question is - do I need to replace the caliper given the amount of play or am I likely to find replacing the slider will reduce the amount of play (The other caliper seems much more robust in comparison)

Here is a pic of the whole where the lower slider runs through:



or another




My guess is that the lower slider has worn beyond use at somepoint and a garage has just tried to fix it without really replacing parts. Alternatively I could be alltogther wrong. This car has been such voyage of discovery it is untrue - I am learning a lot, but every time I touch something I end up with more questions than answers.

I open this one to the floor hoping for someone to make sense of my utter confusion.

[Nelly Vx]

The slider on the lower bolt should be a metal sleeve, someone has obviously put that plastic sleeve in to take the slack out , sirprised it has not gone sooner

[Mangham54]

The slider on the lower bolt should be a metal sleeve, someone has obviously put that plastic sleeve in to take the slack out , sirprised it has not gone sooner

There was a metal slider on the lower bolt, but also the piece of plastic !

I take it the black part on the Elise-Parts site is supposed to be in the caliper itself - there was something in the caliper, but looked more rubbery than plasticky or black metal like!

EDIT: I have just also had a look at the Seloc Wikipage: http://wiki.seloc.or..._Brembo_Caliper and the pics of the black outer sleeve on their pic looks a little more robust than on mine.... again I take it that is the black part on the ElisePart refurb parts picture.

If anyone else has some close up pictures of what it should look like that would be a massive help.

Edited by Mangham54, 14 June 2010 - 09:47 PM.

[techieboy]

I've got the white plastic insert on both of my rear calipers. I've also got a reserve pai of rear calipers and one of them has the insert (I guess the other was lost at some point).

[Mangham54]

I've got the white plastic insert on both of my rear calipers. I've also got a reserve pai of rear calipers and one of them has the insert (I guess the other was lost at some point).

Hmmm.... The plot thickens!

I am right in thinking that there should be no lateral play on the sliders - might even explain the knocking on that particular corner of the car on bumps and the rear track control arm rod ends don't feel like they have any play in them.

[techieboy]

No idea, mine have some very slight play in them but doesn't seem to be any problem with them after the handbrake mechanism was freed off at TMS probably 3+ years ago. I'd always assumed the plastic insert was there to assist the sliding function but maybe it is to take up some play. I've got a couple of the refurb kits sat in the garage and the insert certainly doesn't come with that kit.

[techieboy]

Looks like it should be there according to TIS

[techieboy]

This is a shitty picture of the Elise-Shop servicing kit for the Brembo that I bought a couple of years back

[Mangham54]

Looks like it should be there according to TIS

I had wondered that if there was too much play then as the handbrake is applied (especially if the footbrake is also being used firmly) that the caliper may twist slightly and allow the handbrake auto-adjustment to wind out an extra bit too much. Therefore when released not quite allow the caliper to open enough to run completely freely and create my build up of temperature in the pad and disc and then the infernal squeaking.

I might just get a service kit ordered from EliseParts or EliseShop and see what happens if I try and repair it... New handbrake cable should arrive tomorrow so will try that first. Looks like the trial and error torture may be the only way forward.

Edited by Mangham54, 14 June 2010 - 10:34 PM.

[Arno]

The small teflon sheet on the bottom slider is normal on the original setup. Any lateral play in the caliper is most likely caused by the large upper mount/slider having play. This is the part that really fixates and stabilises the caliper. The bottom one is really only there to stop the caliper from rotating away from the disc under load and not there to really stop it moving around. The top slider is a quite substantial steel tube that has a tight fit in the upper guide of the caliper and is the main 'anchor' for the caliper. If the boots are damaged then dirt can get into the slider and wear the tube or caliper hole. The slider refurb kit replaces the bottom rubber insert and is tighter than the original one. You won't be able to re-use the teflon sheet/tube in this case and it's not really needed anymore. For lubrication of the sliders use a thick silicone based grease, *not* a petroleum/oil based grease as this will soften the rubber and seals. In any case the rear caliper design will always allow it to move around a little. This is normal and unavoidable in such a single piston sliding caliper design. You will always notice that the handbrake can be pulled up higher when the foot brake is applied and vice-versa the foorbrake will feel more solid when the handbrake is applied. Bye, Arno.

[techieboy]

Thanks Arno. As helpful as ever.

[redvts]

All the brakes I have done on VXs have all had the white sleeve, I assume it's some kind of PTFE to stop the caliper seizing onto the slider just read above it's Teflon

Edited by redvts, 15 June 2010 - 06:50 AM.

[FLD]

Yeah, I have the white plastic too. If you need a metal sleeve making give me a shout.

[SteveA]

When you say play, which direction to you mean? Front to back of car or towards and away from the car? It is supposed to slide towards and away as that is how single pot calipers work there shouldn't be much in the way of tolerance front to back though. Eta - mine also has the white sleeve.

Edited by SteveA, 15 June 2010 - 07:56 AM.

[Mangham54]

When you say play, which direction to you mean? Front to back of car or towards and away from the car? It is supposed to slide towards and away as that is how single pot calipers work there shouldn't be much in the way of tolerance front to back though.

Eta - mine also has the white sleeve.

The play allows the caliper on the bottom slider to move about 1-2mm perpendicular to the natural sliding along the piston (if that makes sense).

Ie I can move the caliper away from the disc to the point where I can create a small knocking of the caliper against the slider forwards and backwards (towards front and back of the car - which manifests itself as a twisting of the caliper on the upper slider.

Hope that makes sense- trying to describe in my phone whilst on a coffee break on a course at work!

Should be able to post a vid on YouTube tonight which may make things a little clearer!

[Mangham54]

Yeah, I have the white plastic too. If you need a metal sleeve making give me a shout.

Mate that is an awesome offer should it be required....

You seem to be keen on the metalworking at the moment - a lost ambition from years previous?

Anyhow... my secondary handbrake cable has arrived from Elise-Shop will unwrap it properly when I get home and get some more pictures up.... Also if I manage to make the time to change the handbrake cable over tonight I will get plenty of pics of the process and then write up a 'how-to guide' as I have yet to find a .org one already - should be a peice of p*ss, but knowing the VX one bit will have seized up solid and take an hour to do rather than 30seconds if it hadn't.

+Given the feedback from the Lotus technician it could be a very useful thread.

[FLD]

Yeah, I have the white plastic too. If you need a metal sleeve making give me a shout.

You seem to be keen on the metalworking at the moment - a lost ambition from years previous?

Yeah, always been a technical geek. Mostly 1/4 mile stuff but done some stuff for track cars and planes in the past. Unfortunately the machines I have are a little limited in capacity but I'll have a craic at anything. Done a bit of casting too when needs must. Did a bellhousing for my cos GBB to T56 a few years back. Like I said techno geek, dont have the B**** for driving too fast.

[Duncan VXR]

Between the various levels of experiance, ability and knowledge we should get together all the bods and build a F1 Macca style version of the vx220 Come on guys donate your gold for the boot lining DG

[FLD]

Between the various levels of experiance, ability and knowledge we should get together all the bods and build a F1 Macca style version of the vx220

Come on guys donate your gold for the boot lining

DG

Well my initial plan was to liner a block and graft on a TVS2300 to a 2.2. That'd move! Much as I love turbo's I've gotten quite fond of the supercharger route.

[techieboy]

TVS2300? More capacity in the compressor than in the cylinders. Interesting.