TechWiki - User contributions [en-gb]

Replace the steering rack

2017-01-15T05:27:31Z

Andy R: /* Re-fitting */

{{Infobox Timetools
|time = 1 hour to remove rack
|tools = 17mm deep socket / 17 mm spanner to release track rod end, 13mm socket, 17mm socket, ratchet, numerous extension bars, 13mm spanner, 32mm spanner, 36mm spanner, 5.5mm allenkey, chisel and hammer (to remove rivnut), drill, 2.5mm and 3mm drill bits, vice
}}

Reading the factory manual will have you believing that it's just undo a couple of bolts and bosh, out it comes.

Err, no. Be prepared to be very uncomfortable:

==Removal==
===S1===
First, loosen the front wheel nuts then jack up the front of the car and place on axle stands. Leave a good amount of space at least on one side as you need room to withdraw the rack.

Remove the front wheels.

Now you need to split the track rod ends from the steering arms. Slacken the nuts off to the end of the thread. At this point, it's worth giving the nut a whack upwards with a copper mallet, as this is sometimes enough to free the joint without reaching for your balljoint splitter. If this doesn't work, you're best to use a scissor-type splitter to free the joint.

Now, with both track rod ends released you need to free the bottom steering column UJ from the rack pinion. To do this, first mark the rack pinion in relation to the bottom UJ. I used a dab of tippex (cos it has a handy brush in the lid!). This will help you get the two parts joind back together again afterwards in such a way that hopefully the steering wheel still points in the right direction! Now remove the bottom pinch bolt (13mm) from the bottom UJ. You'll need to get a 13mm spanner on the nut to stop it turning with the bolt.

Now you can remove the 4 bolts that hold the steering rack to the bulkhead. There's two on the bulkhead on the passenger side, and 2 on the bulkhead on the driver's side. The bottom ones need a 13mm socket, the top ones are 17mm socket. I used 2 12" extensions and a 6" extension on the sockets so I could sit in the seats and do it in relative comfort without being upside down in the footwells. Once you've cracked the bolts off and start undoing them, you may find that they're quite hard to turn until they're almost out. This is because they are coated in threadlock and is quite normal.

WIth the bolts out, you should be able to wiggle the rack towards the front of the car a bit, and then wiggle the bottom steering column UJ so that it comes off the rack pinion and you can swing it out of the way.

I then pulled out the rubber grommet around the hole in the bulkhead that the pinion comes through, as this will give you a bit more room in a minute.

Theory goes you should now be able to push the rack towards the front of the car so the pinion clears the bulkhead hole, then slide the rack out.

However, no amount of wiggling back and forth worked on mine. The problem is a rivnut on the front face of the steering rack channel that prevents the rack moving far enough forwards to clear the bulkhead. If you look in the front services compartment, you'll see it just above the outlet from the heater motor. This rivnut isn't needed on right hand drive cars.

I used a sharp chisel to knock the front face off it (in the front services compartment). Then a long screwdriver and a healthy whack to the back of it down the steering rack channel got rid of it.

You should now be able to get in the footwell and tilt the steering rack pinion upwards and it should just clear the hole in the bulkhead. Then just withdraw the rack along the channel.

===S2===
No different to S1 described above for me, apart from there is no need to remove the rivnut, just ask for someone to help you twist it out, it will come.

==Reconditioning==
The rack is made by [http://www.titan.uk.net Titan Motorsport], and they will sell all parts to the public on the condition of a £25 minimum order value. And to be honest, they are very helpful too!

I removed my rack as there was play, which I suspected to be the nylon cups at the inner end of each track rod.

I ordered 2 of the cups (£3.50 each), 2 of the springs that sit behind the cups (£ ), 2 of the locking pins that lock the cups to the locking nuts (£ each), and 2 gaitors (£4.50 each).

[From Titan Motorsport, March 2007: A1161611200A3 - £3.35EA - Nylon shoes, A1161610900A3 - 52p - Spring, A1161916700A3 - 28p - Locking Pin. Note: There is a minimum charge fee of £25]

[http://www.manser42.freeserve.co.uk/Steering%20rack%20parts.jpg Steering Rack overhaul common parts]

This seems to be the most common cause of play in the rack.

[http://www.manser42.freeserve.co.uk/Elise%20Steering%20rack.pdf Steering Rack exploded view courtesy of Titan Motorsport]

You will need to source grease to re-build your rack. The "rocol MTS1000" is now know as "rocol Sapphire hi-pressure bearing grease" and the "scheerol mpt2 grease" is actually called "spheerol mp2". I sourced this from RS but there are other places that sell them. Note 400g is a lot but that was all they had at the time I ordered.
RS Stock No. Qty Unit Price Goods Value Description
198-3136 1 £2.82 £2.82 Spheerol MP2 bearing grease,400gm
330-6288 1 £14.15 £14.15 Sapphire hi-pressurebearing grease,400gm
288-4793 1 £6.00 £6.00 Pocket spring balance w/hook & ring,30kg
Running Total £22.97
Delivery charge £4.95
VAT £4.19 Order total £32.11

Start by removing the cable ties that hold the gaitors on and sliding the gaitors back to the track rod ends (I left the track rod ends in situ, the theory being the tracking wouldn't be too far out when I put it back together).

This exposes the inner ends of the track rods and the cup joint that they sit in.

You will see that the cup joint has a locknut. Between the lock nut and cup joint body there is a small locking pin (roll pin) that needs to be carefully drilled out (using a 2.5 / 3mm drill bit).

Once the locking pin it removed, it should be possible to (carefully) clamp the rack bar in a vice and undo the locknut using a 32mm spanner.

Once the locknut is released, the cup joint will unscrew from the end of the rack.

Remove the cup joint noting the nylon cup and spring that are in there.

Repeat for the other track rod.

Before reassembly (using new sockets) you need to hone the new sockets to the ball surfaces using a light grinding compound. If this is not done the required load setting will be lost within a few hundred miles.

Upon reassembly the two joints should be tightened to a point where a load of 3 to 4 Kg, applied 152mm down the track control arm from the centre of the ball in the joint (ie right near the end), is required to move it. Lock at this point, re-drill, and pin. A centre punch on the end of the locking pin will spread it slightly, securing it.

At this point, I'd noticed that my rack preload seemed far to loose, in that I could turn the pinion shaft with just my finger and thumb, and that when I did this the rack, to my mind, sounded "noisy". There was also one point in the travel where it went "tight".

I made the decision to strip down the rack and re-lube it.

First step in doing this is to remove the pinion. To do this, first undo the Rack Bar Thrust Pad bolt locking nut using a 36mm spanner, then back out the thrust pad bolt using a 5mm allen key. Then remove the circlip that holds the pinion assembly in, and then use your vice and suitable sockets to press it out of the rack body.

You can then carefully withdraw the rack from the end of the rack body.

After a bit of cleaning and degreasing, I found that the internals were pretty much fine, with the exception of a marked tooth on the rack which was causing the tight spot I'd noticed. I just dressed this with a fine file.

Upon reassembly the Rack Bar Thrust Pad should be adjusted to give a preload that allows a horizontaly mounted rack to be pulled along its entire length by a force of 50 - 70 N.

==Re-fitting==

If you slacken both the upper and lower steering column intermediate shaft universal joint cotter bolts, you can get sufficient axial play to ease re-assembly of the bottom joint onto the rack spline with the rack already bolted in place. Once loosened, the upper joint has an amount of axial slack on the intermediate shaft to allow for any installation tolerance

Note: If, for whatever reason, you remove the bottom joint from the end of the intermediate shaft, take care when reassembling that the orientation of the joint is correct to the shaft. The cotter bolt clearance is not a complete revolution in the manner of the pinion spline, so orientation is critical to getting the bolt inserted. Hard to spot when operating by feel down in the footwell!

[[Category:DIY]]
[[Category:Lotus Elise]]
[[Category:S1]]
[[Category:S2]]

Replace the steering rack

2017-01-15T05:26:29Z

Andy R:

{{Infobox Timetools
|time = 1 hour to remove rack
|tools = 17mm deep socket / 17 mm spanner to release track rod end, 13mm socket, 17mm socket, ratchet, numerous extension bars, 13mm spanner, 32mm spanner, 36mm spanner, 5.5mm allenkey, chisel and hammer (to remove rivnut), drill, 2.5mm and 3mm drill bits, vice
}}

Reading the factory manual will have you believing that it's just undo a couple of bolts and bosh, out it comes.

Err, no. Be prepared to be very uncomfortable:

==Removal==
===S1===
First, loosen the front wheel nuts then jack up the front of the car and place on axle stands. Leave a good amount of space at least on one side as you need room to withdraw the rack.

Remove the front wheels.

Now you need to split the track rod ends from the steering arms. Slacken the nuts off to the end of the thread. At this point, it's worth giving the nut a whack upwards with a copper mallet, as this is sometimes enough to free the joint without reaching for your balljoint splitter. If this doesn't work, you're best to use a scissor-type splitter to free the joint.

Now, with both track rod ends released you need to free the bottom steering column UJ from the rack pinion. To do this, first mark the rack pinion in relation to the bottom UJ. I used a dab of tippex (cos it has a handy brush in the lid!). This will help you get the two parts joind back together again afterwards in such a way that hopefully the steering wheel still points in the right direction! Now remove the bottom pinch bolt (13mm) from the bottom UJ. You'll need to get a 13mm spanner on the nut to stop it turning with the bolt.

Now you can remove the 4 bolts that hold the steering rack to the bulkhead. There's two on the bulkhead on the passenger side, and 2 on the bulkhead on the driver's side. The bottom ones need a 13mm socket, the top ones are 17mm socket. I used 2 12" extensions and a 6" extension on the sockets so I could sit in the seats and do it in relative comfort without being upside down in the footwells. Once you've cracked the bolts off and start undoing them, you may find that they're quite hard to turn until they're almost out. This is because they are coated in threadlock and is quite normal.

WIth the bolts out, you should be able to wiggle the rack towards the front of the car a bit, and then wiggle the bottom steering column UJ so that it comes off the rack pinion and you can swing it out of the way.

I then pulled out the rubber grommet around the hole in the bulkhead that the pinion comes through, as this will give you a bit more room in a minute.

Theory goes you should now be able to push the rack towards the front of the car so the pinion clears the bulkhead hole, then slide the rack out.

However, no amount of wiggling back and forth worked on mine. The problem is a rivnut on the front face of the steering rack channel that prevents the rack moving far enough forwards to clear the bulkhead. If you look in the front services compartment, you'll see it just above the outlet from the heater motor. This rivnut isn't needed on right hand drive cars.

I used a sharp chisel to knock the front face off it (in the front services compartment). Then a long screwdriver and a healthy whack to the back of it down the steering rack channel got rid of it.

You should now be able to get in the footwell and tilt the steering rack pinion upwards and it should just clear the hole in the bulkhead. Then just withdraw the rack along the channel.

===S2===
No different to S1 described above for me, apart from there is no need to remove the rivnut, just ask for someone to help you twist it out, it will come.

==Reconditioning==
The rack is made by [http://www.titan.uk.net Titan Motorsport], and they will sell all parts to the public on the condition of a £25 minimum order value. And to be honest, they are very helpful too!

I removed my rack as there was play, which I suspected to be the nylon cups at the inner end of each track rod.

I ordered 2 of the cups (£3.50 each), 2 of the springs that sit behind the cups (£ ), 2 of the locking pins that lock the cups to the locking nuts (£ each), and 2 gaitors (£4.50 each).

[From Titan Motorsport, March 2007: A1161611200A3 - £3.35EA - Nylon shoes, A1161610900A3 - 52p - Spring, A1161916700A3 - 28p - Locking Pin. Note: There is a minimum charge fee of £25]

[http://www.manser42.freeserve.co.uk/Steering%20rack%20parts.jpg Steering Rack overhaul common parts]

This seems to be the most common cause of play in the rack.

[http://www.manser42.freeserve.co.uk/Elise%20Steering%20rack.pdf Steering Rack exploded view courtesy of Titan Motorsport]

You will need to source grease to re-build your rack. The "rocol MTS1000" is now know as "rocol Sapphire hi-pressure bearing grease" and the "scheerol mpt2 grease" is actually called "spheerol mp2". I sourced this from RS but there are other places that sell them. Note 400g is a lot but that was all they had at the time I ordered.
RS Stock No. Qty Unit Price Goods Value Description
198-3136 1 £2.82 £2.82 Spheerol MP2 bearing grease,400gm
330-6288 1 £14.15 £14.15 Sapphire hi-pressurebearing grease,400gm
288-4793 1 £6.00 £6.00 Pocket spring balance w/hook & ring,30kg
Running Total £22.97
Delivery charge £4.95
VAT £4.19 Order total £32.11

Start by removing the cable ties that hold the gaitors on and sliding the gaitors back to the track rod ends (I left the track rod ends in situ, the theory being the tracking wouldn't be too far out when I put it back together).

This exposes the inner ends of the track rods and the cup joint that they sit in.

You will see that the cup joint has a locknut. Between the lock nut and cup joint body there is a small locking pin (roll pin) that needs to be carefully drilled out (using a 2.5 / 3mm drill bit).

Once the locking pin it removed, it should be possible to (carefully) clamp the rack bar in a vice and undo the locknut using a 32mm spanner.

Once the locknut is released, the cup joint will unscrew from the end of the rack.

Remove the cup joint noting the nylon cup and spring that are in there.

Repeat for the other track rod.

Before reassembly (using new sockets) you need to hone the new sockets to the ball surfaces using a light grinding compound. If this is not done the required load setting will be lost within a few hundred miles.

Upon reassembly the two joints should be tightened to a point where a load of 3 to 4 Kg, applied 152mm down the track control arm from the centre of the ball in the joint (ie right near the end), is required to move it. Lock at this point, re-drill, and pin. A centre punch on the end of the locking pin will spread it slightly, securing it.

At this point, I'd noticed that my rack preload seemed far to loose, in that I could turn the pinion shaft with just my finger and thumb, and that when I did this the rack, to my mind, sounded "noisy". There was also one point in the travel where it went "tight".

I made the decision to strip down the rack and re-lube it.

First step in doing this is to remove the pinion. To do this, first undo the Rack Bar Thrust Pad bolt locking nut using a 36mm spanner, then back out the thrust pad bolt using a 5mm allen key. Then remove the circlip that holds the pinion assembly in, and then use your vice and suitable sockets to press it out of the rack body.

You can then carefully withdraw the rack from the end of the rack body.

After a bit of cleaning and degreasing, I found that the internals were pretty much fine, with the exception of a marked tooth on the rack which was causing the tight spot I'd noticed. I just dressed this with a fine file.

Upon reassembly the Rack Bar Thrust Pad should be adjusted to give a preload that allows a horizontaly mounted rack to be pulled along its entire length by a force of 50 - 70 N.

==Re-fitting==

If you slacken both the upper and lower steering column intermediate shaft universal joint cotter bolts, you can get sufficient axial play to ease re-assembly of the bottom joint onto the rack spline with the rack bolted in place. Once loosened, the upper joint has an amount axial slack on the intermediate shaft to allow for any installation tolerance

Note: If, for whatever reason, you remove the bottom joint from the end of the intermediate shaft, take care when reassembling that the orientation of the joint is correct to the shaft. The cotter bolt clearance is not a complete revolution in the manner of the pinion spline, so orientation is critical to getting the bolt inserted. Hard to spot when operating by feel down in the footwell!

[[Category:DIY]]
[[Category:Lotus Elise]]
[[Category:S1]]
[[Category:S2]]

Over 100k

2010-01-03T11:21:36Z

Andy R: /* The Over 100,000 Miles Club */

===The Over 100,000 Miles Club===

{| border="1"
! Name !! Car
|-
| [http://forums.seloc.org/m/woody72 woody72]
|| S2
|-
| [http://forums.seloc.org/m/Jaye.Tillson Jaye.Tillson]
|| S1
|-
| [http://forums.seloc.org/m/Edw Edw]
|| S1
|-
| [http://forums.seloc.org/m/Arno Arno]
|| S2
|-
| [http://forums.seloc.org/m/reAnimate reAnimate]
|| S1
|-
| [http://forums.seloc.org/m/oneslip Oneslip]
|| S1
|-
| [http://forums.seloc.org/m/BrianDrought BrianDrought]
|| S1
|-
| [http://forums.seloc.org/m/Liam Liam]
|| S1
|-
| [http://forums.seloc.org/m/GaryDVO GaryDVO]
|| S1
|-
| [http://forums.seloc.org/m/Tigga! Tigga!]
|| S2
|-
| [http://forums.seloc.org/m/Onch Onch]
|| S1
|-
| [http://forums.seloc.org/m/Hugh.N Hugh.N]
|| S1
|-
| [http://forums.seloc.org/m/Steve69 Steve69]
|| S1
|-
| [http://forums.seloc.org/m/Black_potato Black_potato]
|| S1
|-
| [http://forums.seloc.org/m/Phil._S Phil._S]
|| S1
|-
| [http://forums.seloc.org/m/Romtootes Romtootes]
|| S1
|-
| [http://forums.seloc.org/m/Tanuki Tanuki]
|| S1
|-
| [http://forums.seloc.org/m/Linds Linds]
|| S1
|-
| [http://forums.seloc.org/m/russcasey russcasey]
|| S1
|-
| [http://forums.seloc.org/m/DoubleD DoubleD]
|| S2
|-
| [http://forums.seloc.org/m/Spunagain Spunagain]
|| S1
|-
| [http://forums.seloc.org/m/jeffers Jeffers]
|| S1
|-
| [http://forums.seloc.org/m/SidewaysMatt SidewaysMatt]
|| S1
|-
| [http://forums.seloc.org/m/Azlan Azlan]
|| S1
|-
| [http://forums.seloc.org/m/Andrew%20S Andrew S]
|| S2
|-
| [http://forums.seloc.org/m/Andy_R Andy_R]
|| S1
|}

===The Over 200,000 Miles Club===

{| border="1"
! Name !! Car
|-
| [http://forums.seloc.org/m/Stu Stu]
|| S1
|}

[[Category:Misc]]

How to Rebuild a Brembo Caliper

2008-10-13T22:05:15Z

Andy R:

Lotus Elise Rear Caliper Rebuild and Upgrade

===Pre-Warning===

'''Before you start taking things apart, first ensure that your calipers are servicable.'''
First make sure that you can remove the tiny grub screw that you can see in this photo. It needs a 4.5mm allen key which is a fairly unusual size.

[[Image:grubscrew.JPG]]

Unfortunately the grub screw sits deeply recesed in the boss of the caliper by 10-12mm. By the time your calipers reach an age where they would befefit from new seals, the thread in the boss has become so corroded that it's nigh-on impossible to remove the grub screw. The easiest solution is to take an angle grinder to the boss and remove the excess material. Cut the boss flush with the top of the grub screw. The heat generated by this also helps to free up the screw.

The other part to check is the 13mm bolt that holds the handbrake arm to the caliper. Make sure that this loosens ass it has a tendency to go soft and shear off.

Bear in mind that it's a straightforward job to refurb the sliders but examine your calipers carefully before attempting to replace the piston seals.

===Repair===

The service manual claims the [[Brembo Caliper]]s fitted to the rear [[brakes]] of the Elise are not fully serviceable.

These instructions were developed by disassembling and reassembling many calipers and are not perfect.

The Lotus Elise rear caliper is sometimes criticised as being too small. The rear caliper can be machined to accept a 38mm or even a 40mm piston and sleeve.

For the 38mm piston, you will need a Brembo 38mm seal, part number 05.5955.57

For the 40mm piston, you will need a Brembo 40mm seal, part number 05.5955.58

This conversion still allows the use of all the other standard size parts that come in the KC-83017 kit.

[[Image:Brembo_Caliper_6.JPG]]

== Procedure ==
=== Disassembly ===

[[Image:Brembo_Caliper_7.JPG]]

Unscrew piston as far as it will go using either a windback tool or stout needle nose pliers, one tip in each hole. Push in and rotate counter clockwise.

[[Image:Brembo_Caliper_8.JPG]]

As the dust boot stretches, pull it out of the groove.
The piston can be pried out with two screwdrivers. An internal snap ring holds it tightly, so be prepared to try a few times and apply some effort. Before it pops, it will feel “springy.” When the snap ring does pop, the piston will go flying, so put a rag over it to keep it from falling. You can use a socket on each side to support the screwdriver.

[[Image:Brembo_Caliper_9.JPG]]

Here’s the prying position (without the dust boot and rag). From this image you can get a perspective of how far up the piston will rise without coming out. The piston can also be removed with air pressure into the brake line supply inlet.

[[Image:Brembo_Caliper_10.JPG]]

Once the piston is out, do not turn the caliper over. There are several loose pieces inside that may fall out.

[[Image:Brembo_Caliper_11.JPG]]

Remove the dust boot.
With a 4mm allen key, remove the screw. This screw has an O-ring around the head, so do not reach in and use pliers. It is also held in with thread lock glue, so it feels a little stuck before it comes loose. It may also drag the whole way out. Use the proper allen key, since the metal is soft and you’ll easily round the hole.

[[Image:Brembo_Caliper_12.JPG]]

After the screw is removed, the threaded disc can be unscrewed and removed. This disc pushes on the inside of the piston when pulling on the parking brake.

[[Image:Brembo_Caliper_13.JPG]]

Without the disc, a ball bearing race, a snap ring, and two washers will be visible in the bore. Turn the caliper over to remove them.

[[Image:Brembo_Caliper_14.JPG]]

Here’s what will fall out:-

Ball bearing

Flat washer

Wave washer

Snap ring

[[Image:Brembo_Caliper_15.JPG]]

Removing the worm thread shaft is next.
Look down into the bore for the internal snap ring. It has several tabs bent to point up at you. With a flat screwdriver, pry the tabs at the ends of the snap ring towards the center of the bore and disengage it from the groove in the wall.

[[Image:Brembo_Caliper_16.JPG]]

Now the worm shaft (and snap ring) can be removed. Notice the tabs.

[[Image:Brembo_Caliper_17.JPG]]

Unscrew the hex stop peg in the boss of the caliper. You will need a 4.5mm allen key which is an uncommon size.

[[Image:Brembo_Caliper_18.JPG]]

Remove the parking brake lever, parking brake shaft dust seal, and push the shaft into the caliper body.
The flat washer tends to stick in the caliper, be sure not to miss it.

[[Image:Brembo_Caliper_19.JPG]]

Remove the ball bearing drive plate, the needle bearing, and the flat washer.
Remove the old piston seal.

=== Reassembly ===

[[Image:Brembo_Caliper_20.JPG]]

Install a new parking brake drive plate shaft O-ring, if needed.
Reinstall the flat washer, needle bearing, and ball bearing drive plate of the parking brake in the caliper body. Make note of where the three ball bearings are; you will need to mate them with the driven plate later.

[[Image:Brembo_Caliper_21.JPG]]

The internal assembly will go back together in this order:-

Wave washer

Flat washer

Ball bearing

Cone screw

Use some thread lock on the O-ringed screw on reassembly.
Install a new O-ring on the screw.

[[Image:Brembo_Caliper_22.JPG]]

To reassemble the caliper, insert assembly into the piston and snap the {coat-hanger quality) internal snap ring into the piston.

[[Image:Brembo_Caliper_23.JPG]]

The snap ring groove is just inside the piston.

[[Image:Brembo_Caliper_24.JPG]]

Take the internal snap ring with the tabs, point the tabs downward, and use the tabs to clip the snap ring into the bottom
edge of the piston.

[[Image:Brembo_Caliper_25.JPG]]

Then screw the worm shaft into the piston as far as it will go.
Install the new piston seal.

[[Image:Brembo_Caliper_26.JPG]]

Stretch the new dust boot over the bottom of the assembled piston, leaving the lower edge of the boot to hang down. You will have to hold the piston over the bore and insert the boot lip into the groove all the way around before inserting the piston into the bore. The boot should look even (no bumps) if done properly.
Make note of where the ball bearing detents are.

[[Image:Brembo_Caliper_27.JPG]]

This is the tricky part. With the boot in the groove, centre the piston to begin pushing it into the bore. Use a c-clamp with a socket covering the parking brake shaft sticking out the bottom, making sure the clamp is pushing the piston straight down. Besides the normal problem of getting past the boot lip and the seal, the driven plate detents and the drive plate ball bearings must mate, otherwise you will not be able to push the piston down far enough for the internal snap ring to find it’s groove.
If the clamp seems to come to a stop and you have not heard the snap ring snap into place, try to rotate the clamp to rotate the piston and line up the ball bearing detents.
A second way is to temporarily attach the parking brake lever under the clamp to rotate the lever, which will move the drive ball bearings back and forth to line everything up.
Rotate the lever clockwise when facing the lever, as this also screws the threaded shaft into the cone shaped washer (ensuring that the piston is not bottoming on the parking brake adjustment.)
In any case, the piston will seem to be very low, lower than the dust boot wrinkles, before the snap ring engages. If the snap ring does not engage, the parking brake system has nothing to push on to “disengage.”

Hint 1: A G-clamp may not provide sufficient force to engage the snap ring. It may take 2-3 tons of pressure on a bench press before you hear the snap ring click into position.

Hint 2: Sometimes you can't push on the brake lever arm with the C-clamp to insert piston, you need to take off the arm and push on casting using socket.

Hint 3: Tons of force may not really be necessary. There are two ways to do it even without a G-clamp. The first way is to wind in the worm shaft in to compress the spring - if you're lucky there will be enough friction to hold the spring compressed. Listen whilst you reassemble it in case it comes un-sprung. If it stays sprung, you should be able to get the snap ring to snap by hand pressure on the piston. Alternatively, mount the caliper in a vice. Using a pair of circlip pliers or whatever tool you use to retract the piston, wind the piston clockwise while at the same time applying a reasonable amount of pressure to drive the piston into the caliper. You should hear the circlip click in place.

When the snap ring engages, reinstall the hex head stop peg.
Using the parking brake lever, rotate the parking brake shaft while looking down into the stop peg boss. You will see the detent in the foot of the worm shaft. Screw in the stop peg so it engages the detent.
You can check the proper operation by now rotating the parking brake lever again (which will push the piston out) and then rotating the opposite direction (which should slightly pull the piston back in.) With larger swings of the lever, this becomes a ratcheting action, so repeated back and forth with the lever will eventually move the piston further and further out; if the snap ring is engaged properly, the piston will slightly retract after each lever movement.

[[Image:Brembo_Caliper_28.JPG]]
[[Image:Brembo_Caliper_29.JPG]]

Once installed, the new 38mm calipers look exactly like the standard system.

Notes:
The brakes usually have to bled twice. It seems that air is trapped in the piston (the recess for the threaded parking brake adjustment rod) that isn’t flushed out during caliper installation.
The O-ring screw is a 10-32 thread. About 10% of the time it breaks when trying to remove it.

[[Category:Brakes]]
[[Category:Lotus Elise]]
[[Category:S1]]
[[Category:S2]]

S1 Wheel Options

2008-08-28T20:41:10Z

Andy R: /* Lotus OEM Technomagnesium (UK) */

==Lotus/OEM==

'''Please Add Your knowledge, Its Easy, Just Press [http://wiki.seloc.org/index.php?title={{PAGENAMEE}}&action=edit EDIT]'''

Alloy wheel weight is very important to the [http://en.wikipedia.org/wiki/Unsprung_weight unsprung weight] of the car.

Stuck on what PCD or Centrebore means, [http://en.wikipedia.org/wiki/Wheel_sizing read here].

If you want different wheels to those listed below, you need pcd converting wheel-spacers like [http://www.eliseparts.com/shop/index.php?main_page=product_info&cPath=165&products_id=219 Hubcentric Wheel Adaptors.] as 4x100pcd is already relatively common.

What you need is simple wheel spacers in 4x100pcd, centre bore 56.6 to make the offset a little more common. These spacers would fit Vauxhall Corsa, Astra F&G, Tigra, Vectra + OPEL Ascona and are therefore pretty easy to come by and quite cheap. [http://www.performancefx.net/wsvauxhall.htm example of cheap spacers]

===Lotus AWI 5-Spoke ===
{{ Infobox_Wheels |
| f_size = 5.5J x 15
| r_size = 7.0J x 16
| f_offset = ET14
| r_offset = ET10
| f_pcd = 95.25
| r_pcd = 95.25
| f_cbore = ?
| r_cbore = ?
| f_weight = 7.10kg
| r_weight = 8.80kg
| f_tyresize = 185/55R15 195/50R15
| r_tyresize = 205/50ZR16 225/45ZR16
| price = complete set inc VAT ???
| web =
| image = [[Image:5spoke.jpg|thumb|S1 5 Spoke OEM Wheels]]
| image2 = [[Image:5spok.jpg|thumb|S1 5 Spoke OEM Wheels]]
| notes = OEM S1 wheels.
Lotus Part Numbers:

Front: A111G0004F

Rear: A111G0005F
}}

===Lotus OZ 6-Spokes (111s, JPS, Type '49')===
{{ Infobox_Wheels |
| f_size = 5.5J x 15
| r_size = 7.5J x 16
| f_offset = ET14
| r_offset = ET10
| f_pcd = 95.25
| r_pcd = 95.25
| f_cbore = ?
| r_cbore = ?
| f_weight = 6.95kg
| r_weight = 9.40kg
| f_tyresize = 195/50R15
| r_tyresize = 225/45ZR16
| price = complete set inc VAT ???
| web =
| image = [[Image:6spoke.jpg|thumb|S1 6 spoke OEM]]
| image2 =
| notes = OEM S1 wheels.
111s are silver. JPS and Type '49' are gold

Lotus Part Numbers:

Front: A111G0013F (111s), A111G0029F (JPS, Type 49)

Rear: A111G0012F (111s), A111G0031F (JPS, Type 49)
}}

===Lotus Rimstock 12-Spoke===
{{ Infobox_Wheels |
| f_size = 5.5J x 15
| r_size = 7.0J x 16
| f_offset = ET14
| r_offset = ET10
| f_pcd = 95.25
| r_pcd = 95.25
| f_cbore = ?
| r_cbore = ?
| f_weight = 7.56kg
| r_weight = 8.62kg
| f_tyresize = ?
| r_tyresize = ?
| price = complete set inc VAT ???
| web =
| image = [[Image:12spoke.jpg|thumb|S1 12 Spoke OEM Wheel]]
| image2 =
| notes = OEM S1 wheels.
Lotus Part Numbers:

Front: A111G6040F

Rear: A111G6041F
}}

===Lotus Victory (Sport160)===
{{ Infobox_Wheels |
| f_size = 6.0J x 15
| r_size = 8.0J x 16
| f_offset = ET10
| r_offset = ET10
| f_pcd = 95.25
| r_pcd = 95.25
| f_cbore = ?
| r_cbore = ?
| f_weight = 8.32kg
| r_weight = 10.0kg
| f_tyresize = 195/50R15
| r_tyresize = 225/45ZR16
| price = complete set GBP 599
| web =
| image = [[Image:silvervictories.jpg|thumb|S1 160 OEM Wheel]]
| image2 =
| notes = OEM S1 wheels.
Lotus Part Numbers:

Front: A111G6032S (Grey), A111G6030S (Silver)

Rear: A111G6033S (Grey), A111G6031S (Silver)
}}

==S1 Exige==

===Lotus OEM===
{{ Infobox_Wheels |
| f_size = 7J x 16
| r_size = 8.5J x 17
| f_offset = ET7
| r_offset = ET5
| f_pcd = 95.25
| r_pcd = 95.25
| f_cbore = ?
| r_cbore = ?
| f_weight = ~8.50kg
| r_weight = 11.20kg
| f_tyresize = 195/50 R16
| r_tyresize = 225/45 R17
| price = complete set inc VAT ???
| web =
| image = [[Image:exw.jpg|thumb|OEM]]
| image2 =
| notes =
Lotus Part Numbers:

Front:?

Rear:?
}}

==340R==

===Lotus OEM Technomagnesium (UK) ===
{{ Infobox_Wheels |
| f_size = 6JJ x 15
| r_size = 8JJ x 16
| f_offset = ?
| r_offset = ?
| f_pcd = 95.25
| r_pcd = 95.25
| f_cbore = ?
| r_cbore = ?
| f_weight = 4.77kg
| r_weight = 5.82kg
| f_tyresize = ?
| r_tyresize = ?
| price = 2000
| web =
| image = [[Image:MAG1.jpg|thumb|Technomagnesio only UK cars was offerd these as replacement for the rimstock ]]
| image2 = [[Image:techmag.jpg|thumb|]]

| notes =
Lotus Part Numbers:

Front:?

Rear:?
}}

===Lotus OEM Rimstock===
{{ Infobox_Wheels |
| f_size = 6J15
| r_size = 7.5J16
| f_offset = ?
| r_offset = ?
| f_pcd = ?
| r_pcd = ?
| f_cbore = ?
| r_cbore = ?
| f_weight = 7
| r_weight = 9,5
| f_tyresize = ?
| r_tyresize = ?
| price = complete set inc VAT ???
| web =
| image = [[Image:MAG2.jpg|thumb|Rimstock Alloy (outside uk std) replacement delivery wheels when magwheels where in production ]]

| notes =
Lotus Part Numbers:

Front:?

Rear:?
}}

==Aftermarket==

[[Category:Wheels and tyres]]

===Speedline Corse Magnesium===
{{ Infobox_Wheels |
| f_size = 6J x 15
| r_size = 8J x 16
| f_offset = ET14
| r_offset = ET10
| f_pcd = 95.25
| r_pcd = 95.25
| f_cbore = ?
| r_cbore = ?
| f_weight = 5,5kg
| r_weight = 7kg
| f_tyresize = 185-195
| r_tyresize = 225-245
| price = 1220
| web =
| image = [[Image:MAG.jpg|thumb|5 Spoke MAG Wheel]]
| image2 =
| notes = OEM S1 wheels.
Lotus Part Numbers:

Front:?

Rear:?
}}

===Dymag Magnesium===
{{ Infobox_Wheels |
| f_size = 6J x 15
| r_size = 8J x 16
| f_offset =
| r_offset =
| f_pcd = 95.25
| r_pcd = 95.25
| f_cbore = ?
| r_cbore = ?
| f_weight =
| r_weight =
| f_tyresize = 185-195
| r_tyresize = 225-245
| price = 1880 complete set inc VAT ???
| web =
| image = [[Image:DYMAG.jpg|thumb|5 Spoke MAG Wheel]]
| image2 =
| notes = OEM S1 wheels.
Lotus Part Numbers:

Front:?

Rear:?
}}

===TMR Forged Alloy===
{{ Infobox_Wheels |
| f_size = 7J x 15
| r_size = 8J x 16
| f_offset = +12
| r_offset = +9
| f_pcd = 95.25
| r_pcd = 95.25
| f_cbore = ?
| r_cbore = ?
| f_weight = 4,65kg
| r_weight = 5,85kg
| f_tyresize = 185-195
| r_tyresize = 225-245
| price = 1880 complete set inc VAT ???
| web = http://www.msar-safety.com/index.php?main_page=index&cPath=12
| image = [[Image:TRM.jpg|thumb|Forged Alloy]]
| image2 =
| notes = OEM S1 wheels.
Lotus Part Numbers:

Front:?

Rear:?
}}

===Eliseparts 12 Spoke Forged Alloy===
{{ Infobox_Wheels |
| f_size = 6,5J x 15
| r_size = 8J x 16
| f_offset =
| r_offset =
| f_pcd = 95.25
| r_pcd = 95.25
| f_cbore = ?
| r_cbore = ?
| f_weight = 5.00 Kg
| r_weight = 6.52 Kg
| f_tyresize = 185-195
| r_tyresize = 225-245
| price = 1700
| web = http://www.eliseparts.com/shop/index.php?main_page=product_info&cPath=77_79&products_id=713
| image = [[Image:EPW.jpg|thumb| 12 Spoke EP Forge Alloy]]
| image2 =
| notes = OEM S1 wheels.
Lotus Part Numbers:

Front:?

Rear:?
}}

[[Category:Lotus Elise]]
[[Category:S1]]

Throttle Position Sensor

2007-05-07T17:55:02Z

Andy R: /* Manual recalibration */

[[Image:TPS.jpg|thumb|left|TPS]]
The '''Throttle Position Sensor''' (TPS) is a potentiometer attached to the [[throttle body]] which notifies the [[ECU]] about the position of the throttle. Among other things it helps the engine maintain a stable idle speed.
{{clr}}

== Common faults ==
The TPS is sensitive to heat, moisture and vibration leading to the failure of some units. The sensor is a sealed unit and cannot be repaired only replaced. A TPS may fail gradually leading to a number of symptoms which can include one or more of the following: -

* '''Poor idle control''': The TPS is used by the [[ECU]] to determine if the throttle is closed and the car should be using the [[Idle Air Control Valve]] exclusively for idle control. A fault TPS sensor can confuse the ECU causing the idle to be erratic or "hunting".

* '''High Idle Speed''': The TPS may report faulty values causing the engine idle speed to be increased above normal. This is normally found in conjunction with a slow engine return to idle speed symptom.

* '''Slow engine return to idle''': A failing TPS can report the minimum throttle position values incorrectly which can stop the engine entering idle mode when the throttle is closed. Normally when the throttle is closed the engine fuel injectors will be deactivated until a defined engine RPM speed is reached and the engine brought smoothly to idle speed. When failing a TPS will not report the throttle closed and fueling will continue causing the engine to return to idle very slowly.

* '''Engine Hesitation on Throttle Application''': The TPS is also used by the [[ECU]] to determine if the driver has applied the throttle quicker than the Manifold Air Pressure sensor can read. The fueling is adjusted acordingly to cope with the sudden increase in air volume, however a faulty sensor can cause the [[ECU]] to ignore this data and the engine will "hesitate" when applying the throttle. In extreme cases with the engine at idle, a sudden application of full throttle can stall the engine.

* '''Engine Misfire''': A fault TPS can report values outside the deined acceptable range causing the [[ECU]] to incorrectly fuel the engine. This is noticable as a slight misfire and can trigger the misfire detection software and/or Malfunction Indicator Lamp (MIL) light on the dashboard. Extreme cases can cause excessing misfires resulting in one or more cylinders being shut down to prevent engine and catalytic converter damage.

== Manual recalibration ==
In all cases a manual recalibration of the TPS may resolve the issues at least on a temporary basis. To recalibrate the TPS: -
# With the engine off, insert the key and turn the ignition to position 2 (On) without starting the engine.
# For MEMS-equipped cars (S1), quickly press and release the accelerator pedal several times (at least 5) using as much of the throttle travel as practicable. This will trigger the ECU into the closed-throttle reference learn algorithm, which has it looking for the lowest measured static throttle position (the closed position). The throttle position calibration is a fixed definition from this point.
# Turn the ignition off, remove the key and wait for the ECU to power down (about 30-40s).
# Start car as normal.

== Replacement ==
It's often sold and replaced as part of the throttle body itself however can be replaced separately.

== External links ==
* http://en.wikipedia.org/wiki/Throttle_position_sensor
* http://en.wikipedia.org/wiki/Potentiometer
* http://www.eliseparts.com/shop/index.php?main_page=product_info&products_id=486

[[Category:Engine]]

Passing your MoT Emissions Test

2006-06-08T11:42:55Z

Andy R:

==Introduction==

Passing ones MoT emissions test with ones Elise appears to be an annual trauma. This page is the beginnings of a 'how-to' guide of hints and tips to help you through.

==A Brief Overview of Emissions Control==

Combustion engines of all types generally burn hydrocarbons (HC)as their primary fuel source.

In the limiting case, hydrocarbons combine with ambient oxygen (O2) to create carbon dioxide (CO2) and water (H2O), however an internal combustion engine is never 100% efficient and this chemical reaction usually has some incomplete products, namely carbon monoxide (CO) and unburned hydrocarbons (uHC).

In addition, the normally inert nitrogen (N2) in the air forms oxides of nitrogen (NOx) during the high temperature and pressure phases of the combustion process.

cont...

==The Lambda Sensor==

Otherwise known as an Oxygen Sensor or a HEGO sensor (Heated Exhaust Gas Oxygen), the Lambda sensor returns a voltage signal which is a non-linear function of the amount of oxygen present in the exhaust

Passing your MoT Emissions Test

2006-06-08T11:34:02Z

Andy R: SELOC TechWiki:Searching moved to Passing your MoT Emissions Test: cocked up setting up this page

MoT Emissions Testing

Passing ones MoT emissions test with ones Elise appears to be an annual trauma. This page is the beginnings of a 'how-to' guide of hints and tips to help you through.

Passing your MoT Emissions Test

2006-06-08T11:30:00Z

Andy R:

MoT Emissions Testing

Passing ones MoT emissions test with ones Elise appears to be an annual trauma. This page is the beginnings of a 'how-to' guide of hints and tips to help you through.

Idle Air Control Valve

2006-06-08T11:20:48Z

Andy R:

==Idle Air Control Valve==
The IACV allows the electronic control unit (ECU, a.k.a. MEMS) to regulate the airflow to the engine independently of the driver's throttle input.

When the engine is idling MEMS uses this control (in parallel with igntion timing modulation) to compensate for varying loads that the engine must overcome to maintain the desired idle speed (i.e. friction, electrical load, A/C compressor load etc)

The IACV is also used to control airflow during load changes between positive and negative torque to provide a throttle damping function to improve the driveability characteristics of the vehicle.

K-Series engined Elises use a Rover IACV (Part No. MLZ100090)

[[Image:IACV.jpg|thumb|none|150px|Idle Air Control Valve (K-Series)]]

If you are suspiscious that your IACV may be stuck/jammed, you can test it by disconnecting and reconnececting the ECU temperature sender with the car ignition on (but not running). If it can move, you'll hear it chatter as it seeks to a new position when you unplug the sensor.