It also happens when the ECU is in protection mode if it detected a timing fault (real or sensor fault). Get a quick plug in diagnosis.

Also happens if oil level is low. On a track day with constant high speed conering you will need it at or near the full mark on the dip stick.

Coolant Cap

Hissing noise from coolant cap

Common fault is that the cap starts leaking, a replacement cap can be bought which usually resolves the problem.

Coolant Level

• If the coolant level is at min when hot and rises to max when hot then dont worry as the Elise seems to blow any excess coolant out the top of the cap. Generally it finds it's own level so as long as it stays there and you don't notice any sudden dropping, everything should be fine.
• Is there any coolant on the drive, is the level dropping in the tank?
• Do you see any coolant on your windscreen? This usually means the radiator has a hole in it.
• Often the pipe attaching onto the radiator can come loose. Just tighten the clip that holds the rubber pipe on. Also the bleed nipple in the hose under the left front wheel arch can leak.
• Another common leak path is through the rubber gasket on the inlet manifold. This is difficult to spot due to inaccessibility (view using a mirror) and the fact that the coolant often evaporates before leaving tell tale signs. Replacement gasket is cheap and effective.
• A pressure test by a garage is cheap and will highlight most leaks (other than head gasket problems) quickly.
• If you have "mayo" on the inside of the oil filler cap then check the Head Gasket Failure section of this site.
• A chemical check for exhaust gases in the coolant will further check for head gasket problems.

Temperatures

Most Elises run at around 87 degrees but this figure does fluctuate both up and down according to weather, driving conditions, etc. The fan should kick in at 102 degrees until the temp comes back down. If the gauge goes over 110 then its recommended to stop and allow the engine to cool - check the coolant level while youre at it.

Keep a close eye on temperatures, especially if you have a K-series engine. If the temperature shoots up rapidly then pull over.

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Remote Stat

As its name suggests the remote thermostat moves the thermostat further away from the cylinder head inlet. The major advantage of this is that it gives more hose length for the cold water to mingle with the already hot water. This reduces the rate of temperature fluctuation in the head with the aim of reducing the risk of head gasket failure. Often the remote thermostat kit includes a thermostat with a reduced opening temp - again this serves to reduce the difference between the water in the hot side of the loop with that in the cold side to reduce potential fluctuations if the thermostat opens rapidly.

Ive just changed mine to an Ally throttle body. I choose 48mm for a few reasons. The 52mm apparently can cause some engines to run lean. IMO if you put a 52mm one on, you would have to declare it as a mod for insurance purposes. The 52mm also causes a bit of Kangarooing at low speed in traffic. The BHP increase would be small. I would go for a 52mm as part of an upgrade package, ie head ported, better exhaust manifold etc etc. HTH

Has anybody put a 56mm throttle body on?

Can't really add too much concrete information to this, however I will add the following thoughts:-

As far as I know, the only benefit of a lot of power boost valves is to stop the fluctuations in pressure during rapid changes in demand (e.g. when you snap the throttle open). Therefore its my understanding that peak power is unaffected. I don't think anybody has reported problems with the standard regulator. You can tweak the standard regulator to give more flow, but more flow does not necessarilly mean more power if your engine does not require it - this mod is only performed when you've modified you engine to the point at which you cannot program the ECU to supply enough fuel under the standard pressure. Too high a pressure can make it difficult to control the idle fuel demand accurately.

If it is a 56mm throttle then it is very large. The standard ECU has an adjustment for air flow by measuring the speed of the air. This assumes a known area of throttle. By putting on a 56mm from a 48mm the std ECU will underestimate the amount of air, and therefore potentially run lean. Also, the rate at which the throttle lets air in as you press the pedal will also greatly increase. Whether you consider this good or not depends on the individual - it reduces the ability to control power at low throttle openings but increases the feeling of response. You would definitely get away with fitting the 56mm throttle body if you also fitted an aftermarket ECU that can be programmed to compensate.

If you are serious about power increases then put your money towards some cylinder head work - this will yield significant improvements in peak and (at a medium state of tune) mid range torque. For less money, a lot of people say good things about changing the exhaust headers/manifold for smoother transitioning aftermarket item - again these give reasonable improvements in midrange power as well as a potential small peak power improvement.

Fuel Pump (K Series cars)

The standard S1 fuel pump runs at approximately 3bar pressure (set by the pressure regulator on the end of the fuel rail on a K-Series).

Pumps of this type have the characteristic that as the flow rate increases (which is required for higher powered engines) the pressure the pump can maintain drops. The exact pressure and flow rate varies from pump to pump, but sufficient fuel for around 220bhp @ 3.3bar pressure is possible from the standard pump.

If more pressure and flow is required (as is the case in Honda engined cars) then currently the only option is a secondary pump. This requires additional plumbing and electrical work, although a higher spec replacement pump for the standard pump is under investigation by 3rd party suppliers.

Fuel Pressure Regulators

It is incorrect to say that more pressure will result in more power. The ECU is programmed to deliver as much fuel as required for any given engine condition. Increasing the pressure will result in rich running unless the ECU is altered accordingly (which is not possible with the standard ECU).

Highly modified engines with high power outputs require more fuel pressure in order to deliver the amount of fuel required in the time available. These engines all have aftermarket ECU's to cope with the changes. The standard regulator can be adjusted to give increased pressure (from 3bar to 3.3bar for K series engines) and has proven sufficient in nearly all cases. This modification should only be performed by experienced people.

The stock ECU (particularly the MEMS) is a sealed unit that cannot be adjusted in any way. Options for tuning vary in cost/complexity and therefore performance.

• At the lowest end of the spectrum is something little more complicated than a resistor. The resistor is placed between the ECU and any number of sensor including air temperature, air pressure etc. This 'fools' the ECU into thinking there is a change in the running conditions and making a suitable fuelling and ignition change. The trouble with this solution is that the effects are held within the ECU and it is difficult to know exactly what is happening in any situation. In a worst case the change has the potential to be catastrophic.
• In the mid-range price bracket there are replacement chips (depending on the ECU used). These are bought from 3rd party suppliers and have settings suitable for performance enhanced engines. These can be an improvement, particularly if you have paid for the chip to be made specifically for you via a mapping session. However, in the worst case the adjustments are for a 'generically' improved engines and not suitable for your engine, or at best case are very effective for your current state of tune but need to be re-purchased if you make a significant change in the future.
• In the upper mid-range are piggy back ECU's. These plug between the standard ECU and car and alter the timing based on user configurable demand. Dynajet offer such a system that is proving very popular on motorbikes. The only problem with these are that the cost of such a system is approaching that of fully mapable and most optimal ECUs.
• The ultimate change is a fully programmable / mappable ECU. This replaces the standard ECU and gives the user complete control over ignition and fuelling under a range of conditions. In theory any aftermarket ECU can be used, although many will require an interface loom to be manufactured and may not support all the functions such as the stock Lucas 5AS engine immobiliser used on the Elise. For this reason the Emerald M3DK ECU is the most popular - it quite literally plugs in instead of the standard unit and replicates all the functionality. It's popularity means that engine maps for most popular combinations exist therefore meaning that the car can be used before being fully mapped, and/or that mapping the engine is easier.

The consensus is that in an otherwise standard car a replacement ECU is of little benefit (and by parallel that simple aftermarket kits will offer little benefit). However, as the modifications become more extensive the performance improvements become more pronounced. With highly modified engines the standard ECU is incapable of correctly controlling the engine at all and therefore an aftermarket fully programmable ECU becomes a requirement.

Otherwise:

1. Check the spring on the throttle body. Clean and oil 2. Check inside the throttle body. Check if the flap sticks. Clean 3. Check the throttle position sensor. Disconnect the electrical connector, clean etc. 4. Check the Idle Air Valve Control (IAVC). It sometimes gets blocked so check the hose to the intake side of the throttle plate. Also check the electrical connector and clean if necessary.

You can reprogramme the sensor by:

Leave drivers door open. Turn ignition to II so dash is lit but engine not cranked. Ensure the immobiliser is deactivated. Slowly press accelerator fully 5 times, then turn off the ignition. Wait 30 seconds then start the engine.

5. Check the Inlet Air Temperature sensor (IAT) which is located onto cylinder 4 of the inlet manifold. Green sensor. Check electrical connection etc etc

Performance Changes

Performance increases are very approximate but are indicated to give some idea of the benefit. The changes listed below are a logical progression of cost and requirement.

• Exhaust backbox/silencer (2->5bhp)
• Air filter (2->5bhp)
• Sports cat(catalytic convertor) / CRP (Cat Replacement Pipe) (2->5bhp)
• Exhaust headers (2->5bhp peak power, but with significant mid-range power improvement)
• Cylinder head work / cam change (variable, but can be taken to approx 160bhp with other standard components)
• Replacement ECU (variable gains, ultimately required to control high spec engines)
• Individual throttle bodies (variable gains and again required to get smooth idle control on high spec engines)
• Strengthened piston/rods and/or capacity increase to 1.9litres (required for high revs and higher power outputs, e.g. c.175bhp+)
• Engine transplant (variety of options including 2litre or 2.3litre Ford Duratecs (190bhp through to 220bhp, although higher outputs possible but untested), 1.8litre Audi Turbo (200bhp to 300bhp) and 2.0litre Honda Vtec in normally aspirated (c.200bhp) or supercharged (c.300bhp). Supercharging the K-series has been historically possible (to around the 260bhp mark) but expensive.
• Toyota engined Elises have now got factory and aftermarket supercharger options.

250 bhp turbo Audi ~ £8K 220 bhp n/a Honda ~ £10K 300bhp+ turbo Audi ~ £10.5K 300bhp s/c Honda ~ £13K

All approx. value installed, to include 6-speed gearbox bundled with engine.

There are other variants: a Ford Duratec can go to 2.3l & 260bhp but nobody's fitting them at the moment, and you can fit a Honda 2.4 block in there too.

To that, you really should add uprated brakes. Suspension will need modifying to compensate for the increased engine weight, so stiffer rear springs at least, or just get Ohlins or Nitron fitted while it's in bits. So budget another £2K for that lot.

Alternatively, get your K-series fettled. Go from 120 > 160bhp for relatively little money and retain plenum-type induction. Get new cams, induction & exhaust plus a head port, valves & polish for around £2.5K (less if you've already got some of those bits). Emerald ECU and d2h throttle bodies another £2.5K, to get over 180 bhp. Beyond that, you'll need forged bottom end bits for another £2.5K fitted. Factor in competition clutch, lightened flywheel, oil cooler & remote stat along the way. Good thing about the K-series route is you can do a bit at a time - who has £10K lying around all in one go?

1. Low oil
2. Hydraulic tappets running a bit dry (a 'spirited' drive can sort this)
3. the fuel purge valve (i think thats what its called) (but it doesn't alter with engine revs)
4. A leaking exhaust manifold
5. A case of the fact that some K-series tend to get all tappety in the winter and its nothing to worry about.
6. Something majorly serious

The noise will be much worse if

• the car is left unused for a few days or
• left unused and then started in this cold weather.

The oil seeps back into the sump ( which is why we talk so much of a good oil as a film of protection should stay on the top end ) and the noise is the clearances 'running dry'. As the oil pumps and warms, the gaps are all cushioned by it....no or little noise. So if the noise is clearing when the engine is warm, no worries. This noise is also letting you know why you should never, ever rev an engine from cold.

So, put your oil questions here but please give the following information if you would like a recommendation:

* Make

* Model

* Year

* Engine size/type

* Any mods

* Type of use (road/track)

* Additional info (max oil temps, current oil used)

* What do you want a recommendation for? Engine, Gearbox etc?

Standard K Series

Good thread idea, i wanted to ask if the oil i'm using is ok for the use of my car. Here goes,

* Lotus Elise S1

* 1998

* K series 1.8 16v

* Only mods to engine are Hurricaine air filter and Raceline Back box.

* Mocal water/oil heat exchanger fitted+ remote stat to cooling system.

* Mainly road use car with minimum of 1 trackday a month, usually covering between 140-180 miles on a t/day.

Stack temp reading stays between 79-83 on road, no higher than 85 on track (even after 20 mins of hard use.)

Gear box oil i'm using at the minute if Castrol TAF-x

Engine oil used is Vavoline VR1 racing 5w-50 fully synthetic.

Should i change from the Gear box/ engine oil i'm using at the minute?

Answer One

Well, the K series was designed to run on sae 40 which is in has a viscosity of 14cst at 100degC oil temp (bulk in the sump).

An sae 50 will have a viscosity of 18cst at 100degC which is in fact quite a bit thicker than needed at 100degC.

On the basis that your oil temps are lower than 100degC the oil will always be thicker than the design parameters at high revs/high temps due to the cooler which as its drawbacks.

With oil that is this cool you could easily get away with a 5w-30 or 5w-40 without problems and not have the potential downsides which are

Lower BHP at the wheels Poorer fuel consumption More oil drag, friction, heat and wear

If you wish to change I would suggest a decent 5w-30 or 5w-40 synthetic (5w-40 would be my preference)

The next question is which oil would I recommend.

If trackdays are a factor then a race oil that can be used on the road with no downsides.

Silkolene Pro S 5w-40 or Motul 300V 5w-40 would be my choice.

The "Stack" Rus mentions is the standard Elise instrument cluster and he's reporting water temp, not oil. However with a water/oil cooler, instead of oil reaching up to 130ºC on track, it is perhaps being pegged to around 100ºC?

Thanks for that, I thought it was oil temp that was being referred to.

The 5w-40's I mention are good for 120degC (bulk oil temp in sump)

Duratec Conversion

I'd be interested in hearing your suggestions for my car:-

* '98 S1 Elise

* Cosworth 240bhp Ford 2.3L Duratec I4

* PG1 Gearbox

* Mainly road use.

* Mocal oil/water cooler.

* Wet Sump

* 85deg C coolant temp (unknown oil)

* 5W-40 Mobil 1 and Castrol SMX-S currently in use in engine/gearbox respectively.

Answer Two

Your choice of oils is fine, 5w-40 is ideal. Others to look at would be Motul and Silkolene.

For the gearbox the Castrol is fine, another to look at would be the Amsoil MTF.

Oil Temp Gauges

I've looked in various archives and the oil temp that others with oil temp gauges seem to be getting is around 120 degrees, i'd imagine mine would be somewhere in that region as well, for the time being i dont have an oil temp gauge fitted but hopefully will have at some point so i'll be able to see what temps the oil is getting to.

Iirc Dobbo has just fitted an oil temp gauge to his car so he might have some figures that would be useful for this thread.

Answer three

QUOTE

(Rus)

Iirc Dobbo has just fitted an oil temp gauge to his car so he might have some figures that would be useful for this thread.

Tis true. Unfortunately, the only decent run it's had so far is the Mids run a couple of weeks ago, so I don't have much to go on so far. It never went above 80s IIRC on that run. I do know that the oil cooler comes on line at about the same time that the coolant on the Stack reaches 50-60deg (from the touch-of-the-hand-ometer. The oil was probably around 50deg when the cooler started coming on line - I have a fairly good idea of what 50deg to the touch feels like as that's the upper limit we can work at in my job. You don't flinch instantly, but can touch it for a few seconds before pulling your hand away, and that's what the cooler pipes were like). After 1/2 hour of idling, however, the pipes were too hot to touch, so probably much the same as the coolant temperature.

Also, however, when I tightened up the connector to the temp sensor there was a slight "cracking" noise, which I assume was the sensor insert breaking its seal with the housing. That means it'll now have a slower response (no chance of an oil leak, though). Eliseparts have said that they will send me a new one when I do my next oil change. I also read recently that putting a sensor in the sump plug is not ideal as it's not really measuring the bulk temperature of the sump oil, and is slow to respond due to it's location (bit of a dead zone, so temperatures only change slowly). I did question this design with Eliseparts but there was no alternative within the design and timeframe that I had to get the car back on the road.

To be honest, if you're measuring oil temperature, there are two measurements that are important :

1 - the supply temperature (to check that you're not supplying oil that's too hot to the bearing) and

2 - the bulk temperature in the sump (to see if it gets overheated during use).

However, without two sensors and gauges, that's not possible !

Perhaps another set of gauges - I can then run two temp gauges, a pressure gauge and a voltmeter so that I can tell when my new audio amp, speakers and sub are drawing too much power ... biggrin.gif

The perfomance and limits of most oils are based on bulk oil temp in the sump.

As a rule of thumb the Silkolene Chemist (the man that invented Pro S and all their race oils) told me that -

Pro S 5w-40 was good to 120degC measured in the sump, after that to use Pro S 10w-50 as this is good for 140degC plus.

Mind you at these temps I'd be worried about something else giving out first, not the oil!

Oil Labelling Explained

What's written on your oil bottle and what does it mean.

This post may seem like going back to basics but I am constantly surprised by the amount of people who do not know or understand what is written on a bottle of oil and therefore no idea of what they are buying/using.

To be blunt about the subject, if a bottle of oil does not contain the following basic information then DO NOT buy it look for something that does!

1) The purpose for which it is intended (i.e. Motor oil, Gear oil etc)

2) The viscosity (i.e. 10w-40, 5w-30 etc for Motor oils and 80w-90, 75w-90 etc for Gear oils)

3) The specifications that it meets (should contain both API and ACEA ratings)

4) The OEM Approvals that it carries and the codes (i.e. MB229.3, VW503.00, BMW LL01 etc)

Ignore the marketing blurb on the label it is in many cases meaningless and I will explain later what statements you should treat this with some scepticism

So, what does the above information mean and why is it important?

THE BASICS

All oils are intended for an application and in general are not interchangeable. You would not for example put an Automatic Transmission Oil or a Gear Oil in your engine! It is important to know what the oils intended purpose is.

VISCOSITY

Most oils on the shelves today are "Multigrades", which simply means that the oil falls into 2 viscosity grades (i.e. 10w-40 etc)

Multigrades were first developed some 50 years ago to avoid the old routine of using a thinner oil in winter and a thicker oil in summer.

In a 10w-40 for example the 10w bit (W = winter, not weight or watt or anything else for that matter) simply means that the oil must have a certain maximum viscosity/flow at low temperature. The lower the "W" number the better the oils cold temperature/cold start performance.

The 40 in a 10w-40 simply means that the oil must fall within certain viscosity limits at 100 degC. This is a fixed limit and all oils that end in 40 must achieve these limits. Once again the lower the number the thinner the oil, a 30 oil is thinner than a 40 oil at 100 degC etc. Your handbook will specify whether a 30, 40 or 50 etc is required.

SPECIFICATIONS

Specifications are important as these indicate the performance of the oil and whether they have met or passed the latest tests or whether the formulation is effectively obsolete or out of date. There are two specifications that you should look for on any oil bottle and these are API (American Petroleum Institute) and ACEA (Association des Constructeurs Europeens d'Automobiles) all good oils should contain both of these and an understanding of what they mean is important.

API

This is the more basic as it is split (for passenger cars) into two catagories. S = Petrol and C = Diesel, most oils carry both petrol (S) and diesel © specifications.

The following table shows how up to date the specifications the oil are:

PETROL

SG - Introduced 1989 has much more active dispersant to combat black sludge.

SH - Introduced 1993 has same engine tests as SG, but includes phosphorus limit 0.12%, together with control of foam, volatility and shear stability.

SJ - Introduced 1996 has the same engine tests as SG/SH, but phosphorus limit 0.10% together with variation on volatility limits

SL - Introduced 2001, all new engine tests reflective of modern engine designs meeting current emissions standards

SM - Introduced November 2004, improved oxidation resistance, deposit protection and wear protection, also better low temperature performance over the life of the oil compared to previous categories.

Note:

All specifications prior to SL are now obsolete and although suitable for some older vehicles are more than 10 years old and do not provide the same level of performance or protection as the more up to date SL and SM specifications.

DIESEL

CD - Introduced 1955, international standard for turbo diesel engine oils for many years, uses single cylinder test engine only

CE - Introduced 1984, improved control of oil consumption, oil thickening, piston deposits and wear, uses additional multi cylinder test engines

CF4 - Introduced 1990, further improvements in control of oil consumption and piston deposits, uses low emission test engine

CF - Introduced 1994, modernised version of CD, reverts to single cylinder low emission test engine. Intended for certain indirect injection engines

CF2 - Introduced 1994, defines effective control of cylinder deposits and ring face scuffing, intended for 2 stroke diesel engines

CG4 - Introduced 1994, development of CF4 giving improved control of piston deposits, wear, oxidation stability and soot entrainment. Uses low sulphur diesel fuel in engine tests

CH4 - Introduced 1998, development of CG4, giving further improvements in control of soot related wear and piston deposits, uses more comprehensive engine test program to include low and high sulphur fuels

CI4 Introduced 2002, developed to meet 2004 emission standards, may be used where EGR ( exhaust gas recirculation ) systems are fitted and with fuel containing up to 0.5 % sulphur. May be used where API CD, CE, CF4, CG4 and CH4 oils are specified.

Note:

All specifications prior to CH4 are now obsolete and although suitable for some older vehicles are more than 10 years old and do not provide the same level of performance or protection as the more up to date CH4 & CI4 specifications.

If you want a better more up to date oil specification then look for SL, SM, CH4, CI4

ACEA

This is the European equivalent of API (US) and is more specific in what the performance of the oil actually is. A = Petrol, B = Diesel and C = Catalyst compatible or low SAPS (Sulphated Ash, Phosphorus and Sulphur).

Unlike API the ACEA specs are split into performance/application catagories as follows:

A1 Fuel economy petrol A2 Standard performance level (now obsolete) A3 High performance and/or extended drain A4 Reserved for future use in certain direct injection engines A5 Combines A1 fuel economy with A3 performance

B1 Fuel economy diesel B2 Standard performance level (now obsolete) B3 High performance and/or extended drain B4 For direct injection car diesel engines B5 Combines B1 fuel economy with B3/B4 performance

C1-04 Petrol and Light duty Diesel engines, based on A5/B5-04 low SAPS, two way catalyst compatible. C2-04 Petrol and light duty Diesel engines, based on A5/B5-04 mid SAPS, two way catalyst compatible. C3-04 Petrol and light duty Diesel engines, based on A5/B5-04 mid SAPS, two way catalyst compatible, Higher performance levels due to higher HTHS.

Note: SAPS = Sulphated Ash, Phosphorous and Sulphur.

Put simply, A3/B3, A5/B5 and C3 oils are the better quality, stay in grade performance oils.

APPROVALS

Many oils mention various OEM's on the bottle, the most common in the UK being VW, MB or BMW but do not be misled into thinking that you are buying a top oil because of this.

Oil Companies send their oils to OEM's for approval however some older specs are easily achieved and can be done so with the cheapest of mineral oils. Newer specifications are always more up to date and better quality/performance than the older ones.

Some of the older OEM specifications are listed here and depending on the performance level of your car are best ignored if you are looking for a quality high performance oil:

VW – 500.00, 501.00 and 505.00

Later specs like 503, 504, 506 and 507 are better performing more up to date oils

MB – 229.1

Later specs like 229.3 and 229.5 are better performing more up to date oils.

BMW – LL98

Later specs like LL01 and LL04 are better performing more up to date oils.

FINALLY

Above is the most accurate guidance I can give without going into too much depth however there is one final piece of advice regarding the labelling.

Certain statements are made that are meaningless and just marketing blurb, here are a few to avoid!

Recommended for use where…………… May be used where the following specifications apply…………… Approved by………………………..(but with no qualification) Recommended/Approved by (some famous person, these endorsements are paid for) Racing/Track formula (but with no supporting evidence)

Also be wary of statements like "synthetic blend" if you are looking for a fully synthetic oil as this will merely be a semi-synthetic.

Like everything in life, you get what you pay for and the cheaper the oil the cheaper the ingredients and lower the performance levels.

If you want further advice then please feel free to ask here or contact us through our website at www.opieoils.co.uk.

Dont forget to pump the spare tyre up.

Okay then, like I said I took the opportunity to also change the cambelt tensioner, alternator belt, water pump and coolant. The belts, pump and tensioner were all sourced from www.eliseparts.com The coolant and de-ionised water were from my local motor factor. The first photo shows these laid out on the bench. The object to pay particular attention too in this photo though is the 'tool' on the right and the cut-down socket. The lack of this tool the first time round was one of the reason's I gave up! It is required to undo the crankshaft pulley bolt which has a 22mm hex head. The cut-down socket is used on a torque wrench to tighten it back up again. For reference, the socket was cut down to 33mm in length and the 'tool' measures 600mm long by 38mm total thickness, including the welded on socket. Also in the photo, is the blue anodised camshaft gear locking tool…

First job was to get the back end of the car jacked up, the higher the better, but making sure it was well supported and the front wheels chocked. You are lying underneath it and putting a lot of force on that aforementioned torque wrench! I removed the undertray and supported the back end of the car with axle stands on the ends of the chassis rails as shown below. (You could also support it under the steel rear sub-frame which, in hindsight, may have been the better option for this job). I then removed the driver's side rear wheel. The wheel arch liner is retained at 5 points, 2 at the rear into rawlnuts (these and their associated screws may need replacing if badly corroded) 2 plastic fasteners at the front and the screw you can see next to the damper in the photo…

Once the wheel arch liner was removed I could access the upper timing belt cover. (The procedure from here on in is pretty well covered in the Elise service manual so refer to that above all else. The only problem with the manual is that it is working on an engine on a bench, not one that is shoe-horned into the back of an Elise). Photo below shows the upper cover and some of the fasteners. (The rusty looking 18mm hex head bolt is one of two on the engine mount that needed to be undone later in order to remove the belt)…

Once the upper cover was removed I was able to see the cambelt and camshaft pulleys. Using the 'tool' and referring to the service manual, I rotated the crankshaft to align the camshaft gear timing marks 90 degrees BTDC. You'll see in the photo below at the 3 o'clock and 9 o'clock positions we put some tipex on the pulleys. The method we use is to then mark the belt at these same 2 positions and a 3rd position relative to the crankshaft pulley. (Once the belt is removed we then transfer these marks from the old belt onto the new one as a back up to make sure we don't end up being a tooth out on the timing. Ignore the marks you can see on the belt in this photo though, as they are the ones from when it was fitted the last time round!)…

With the upper cover removed you can also see the cambelt tensioner and below it, the water pump. At the bottom of this photo you'll also notice a coolant stain coming from the pump, so it's probably just as well I'd decided to replace it anyway!

The next step was to undo the dreaded crankshaft pulley bolt. Here is a photo from underneath that gives you some, but not much of an idea of how close the crankshaft pulley is to the chassis side rail. (Unfortunately you can't see the bolt itself but you can see the alternator belt that has to come off so may as well be changed for a new one while you're there)…

In order to wield the tool in the first photo I had to jack the car a bit higher so the tool could hang vertically down from the pulley. Doing this enabled about 60 degrees of swing. The following photo shows the bigger axle stands and the sort of height I raised the car to…

To undo the crankshaft pulley bolt you need to be able to react against something, or else you'll just be turning the engine over. It is not physically possible to use the flywheel locking tool (Part No 18G 1571) referred to in the Elise service manual so you have to improvise. The first time we did this on my car we used the method of putting the car in gear and someone carefully getting in the car and pressing the brake pedal as hard as possible. It worked but there is a lot of wind-up of the gear-train, which is probably not a good thing, plus it all seemed a bit too dangerous to be honest. The best way is to try and lock the starter ring. There are some people who do this by removing the starter motor to gain access to the starter ring and then locking it with a suitably sized screwdriver and others who do it like 'we' did by again, locking it with a screwdriver through a suitable opening like the one shown below, near the inboard end of the driver's side driveshaft…

I used the term 'we' just now because it is at this point that I once again handed over to Brian (Elise+Imp). Brian has been a very good friend for some years now and in my opinion his engineering know-how is unsurpassed. From a farming background and with a Degree in Mech Eng I have yet to see anything that he can't turn his hand to. You've only got to see his Hillman Imp to see what he's capable of! He has done no end of cambelt changes, a good half a dozen on S1 Elises. With the added benefit of his four-post lift he reckons on about 4 hours from start to finish to change just the cambelt. If you decide you lack the confidence to tackle this job yourself, don't want to pay dealership prices and are not bothered about a stamp in your logbook then I can't recommend him highly enough. So, plug over, Brian locked the starter ring with a screwdriver and undid the crankshaft pulley bolt with the 'tool'. This released the pulley, the alternator belt and allowed access to be able to remove the lower timing belt cover. We then put the camshaft gear locking tool into place ensuring everything was still aligned correctly…

In order to remove the belt you have to first remove the two hex head bolts from the engine mount because the mount itself is within the loop of the belt. Before doing this we supported the engine with a trolley jack under the sump, protecting the sump with a piece of wood. You can see the 2 bolts in this photo…

After undoing the bolts a little and carefully lowering the jack you can see the joint starting to separate in this photo…

Once the joint was fully separated and the tensioner slackened off, we removed the old cambelt through the newly opened joint. Here's a photo of the new belt ready with the tipex markings transferred over from the old belt…

Whilst Brian had been transferring the timing marks I removed the water pump. Not sure why but when you look at the service manual it tells you to remove the thermostat housing before removing the water pump, which is not necessary. Repeating an earlier photo below, you'll see there are 4 conventional bolts, a pillar bolt in the bottom right hand corner and not so obvious, a bolt fitted from the back, in the top left hand corner. It is also dowelled at 2 positions, one of which you can also see in the top left hand corner…

I removed the pump and caught most of the coolant. Was going to be changing it any way but if you can avoid creating a slick all over the garage floor it's a bonus!

Here's a photo comparing the old and new pumps. I have to say, although it had obviously started weeping a little and needed changing, I much prefer the look of the nice stainless impeller to the cast affair on the new one…

Here's another of the old pump showing the leak…

Here's what you see in the engine when the pump is removed, all looks nice and shiny. You also get a better picture of the 2 dowels…

I secured the o-ring in the new pump with some RTV sealant as per the service manual and fitted the assembly back onto the engine. Might have overdone the sealant as it oozed out a bit!

We then fitted the new tensioner and the new belt ensuring that the tipex marks on the belt aligned with those on the pulleys. We then applied threadlock to the 2 engine mount bolts and torqued them back up. Here's a photo of the new tensioner fitted but yet to be tensioned…

Barely visible in the above photo is the pointer (just behind the teeth of the belt and about 2 teeth below that, the index wire with which it has to be aligned to set the tension).

We refitted the lower timing belt cover, cleaned up the threads of the crankshaft pulley bolt, applied some threadlock to it and then refitted the crankshaft pulley. This requires a torque wrench capable of 205Nm, the 22mm socket that has been cut down in length makes life a whole lot easier too! Once more, the starter ring was locked using the screwdriver method. (Make sure you've removed the camshaft gear locking tool before torque tightening!)

We set the tension and rotated the engine a couple of times, as per the manual, to make sure the setting didn't alter and that no valves and pistons were crashing together! Once we were happy with everything and I'd temporarily replenished the coolant, we fired it up again.

After all that, it was just a matter of refitting the upper timing belt cover, wheel arch liner, wheel and ordinarily, the undertray, but I was going to change the coolant whilst I was at it so I'll go onto that now…

To drain the coolant the car needs to be level, or slightly nose up, but high enough off the ground that you can get under it. Jacking the car up with some large blocks of wood under each wheel is one method of achieving this. As with the cambelt, please refer to the Elise service manual for further detailed information on the drain and refill procedure. I first undid the expansion bottle cap and then got underneath to undo the relevant jubilee clips from the hoses. There are two jubilee clips that need to be undone. One smaller one on the driver's side where the metal pipe emerges from the sill…

and the other larger one on the passenger side, coming out at right angles to the sill…

Here's the driver's side disconnected and draining…

And here's the passenger side disconnected and drained, pretty much like I was at this point!

Unless you plan on removing the heater matrix you will not be able to drain out the full 8 litres from the system, reckon on about 6 litres. After another hopeless attempt at catching the coolant and once I'd again mopped up the slick from the garage floor, I reconnected the hoses. Something to be aware of is there are compatibility problems between different types of antifreeze, so it's important to either use the same type or flush the system completely with clean water prior to putting the new anti-freeze in. (I was using the same OAT based antifreeze as previously so didn't need to flush it all out). I then removed the engine bay bleed screw, visible as the shiny hex-head screw next to the HT lead in the photo below…

I then refilled with a 50/50 mix of antifreeze and de-ionised water. Although the service manual suggests pressurising the system I have had no trouble in relying on gravity to do the job for me. Once the coolant started flowing out of the bleed point (another slick on the garage floor!) I re-fitted the bleed screw. Next step was to open the radiator outlet bleed screw. You find this one more by feel than looking. If you turn the steering to full RH lock and bend the front of the LH wheel arch liner back, then shine a torch in, you should be able to just make out the brass bleed screw. Took a few attempts but just about managed a photo of this one too. You can see the protrusion coming up from the hose and then on top of that is the brass knurled top of the bleed screw…

I opened this one and waited for the hissing to stop and the coolant to start flowing out before tightening again.

After that, I ran the engine up as per the service manual instructions, re-bleeding at the radiator as necessary, re-fitting the expansion bottle cap and waiting for the rad fan to cut in and out.

Once it had all cooled down again I topped up the expansion bottle to the min mark and that was it.

Job done!

All in all, it took around 9 hours to do all of the above. I guess to have had this all done at a Dealership you'd be looking at a bill approaching a grand whereas this has cost me around £130 in parts and materials plus a huge thank you to Brian of course!