Caterham 7 R300 Superlight
Discussion
Since everyone just scrolls down to see a picture before reading the text, here it is 
It's a 2012 R300 Superlight with a Ford Duratec putting out 180bhp. They're quite rare from what I gather, not that many were sold as they didn't produce them for long. It has all the usual Superlight bits on it, such as 6 speed close ratio box, LSD, adjustable suspension, 13" wheels (6" front, 8" rear), lots of carbon bits, tillett seats and an FIA rollbar.
The story starts after the sale of my first Caterham which I documented in Reader's Cars here. As the thread showed, I steadily upgraded and refreshed the car to the point I was really happy with it...and then I sold it! I was in Afghanistan and having returned home, my wife informed me she'd found our forever house. The house was (is) spot on, the timing however, was appalling. We did buy it but it cleaned us out and the Caterham had to go to help pay for it. I got my double garage and consoled myself with a 205 GTi and then a Lotus Elise S1 (threads here and here) whilst I saved up for another.
Fast forward to early 2018, I'd saved up, now to find the right car. Anyone who knows about Caterhams will attest to the fact that no two cars are the same. So, being pretty picky and knowing exactly what I wanted was not going to make life easy. I put the feelers out to the specialist dealers and waited. Just a couple of weeks later I got a phone call saying an Viper Blue R300 was coming in. The spec sounded great although the only photo on the website looked pretty like this:
(Yes it's blue and the car is yellow )
Figuring that anything on a 7 can be changed if I didn't like it, I put a deposit down. I was told that cosmetically it wasn't great but being that I hated Viper Blue anyway, and it would be getting a respray I wasn't really bothered. I collected the car in early March and drove it home with my son for company.
Obligatory MaccyD on the way home!
First job was to sort the pedals out for better comfort and easy heel and toeing. These cars are joy to heel and toe but only after removing the accelerator pedal and bending it in a vice to get it closer to the brake. It's pretty easy, just remove the pedal box cover, disassemble the pedal to modify, then reverse the process.
I also took the opportunity to do a couple of minor bits in the engine bay, protecting cables etc and making sure it all worked properly.
About this time, I managed to go through the history folder properly. Every single invoice/mot/service sheet is there which is great for satisfying my OCD tendencies and chatting to the previous owner too was really helpful. It's million stonechips was explained by it being exclusively a track car but the upside is that it has been fastidiously maintained with a lot of money spent. So, through summer of 2018, I just drove it as much as I could (including one track day at Abingdon, forgot to take pictures though) and concentrated on getting to know it. Compared to my K Series R300, it's definitely faster and has got waaaay more mid-range torque, so gear selection for overtakes isn't so critical and it accelerates well. Handling seems as great, some people say the heavy Duratec blunts the front end, but I'm not good enough to tell and the setup already on the car ensured the front end was very pointy anyway.
Visit to Prescott Hill Climb with a mate in his 7:
Come winter 2018 it was tucked up in the garage ready for a bloody good service and springtime 2019......
It's a 2012 R300 Superlight with a Ford Duratec putting out 180bhp. They're quite rare from what I gather, not that many were sold as they didn't produce them for long. It has all the usual Superlight bits on it, such as 6 speed close ratio box, LSD, adjustable suspension, 13" wheels (6" front, 8" rear), lots of carbon bits, tillett seats and an FIA rollbar.
The story starts after the sale of my first Caterham which I documented in Reader's Cars here. As the thread showed, I steadily upgraded and refreshed the car to the point I was really happy with it...and then I sold it! I was in Afghanistan and having returned home, my wife informed me she'd found our forever house. The house was (is) spot on, the timing however, was appalling. We did buy it but it cleaned us out and the Caterham had to go to help pay for it. I got my double garage and consoled myself with a 205 GTi and then a Lotus Elise S1 (threads here and here) whilst I saved up for another.
Fast forward to early 2018, I'd saved up, now to find the right car. Anyone who knows about Caterhams will attest to the fact that no two cars are the same. So, being pretty picky and knowing exactly what I wanted was not going to make life easy. I put the feelers out to the specialist dealers and waited. Just a couple of weeks later I got a phone call saying an Viper Blue R300 was coming in. The spec sounded great although the only photo on the website looked pretty like this:
(Yes it's blue and the car is yellow
)Figuring that anything on a 7 can be changed if I didn't like it, I put a deposit down. I was told that cosmetically it wasn't great but being that I hated Viper Blue anyway, and it would be getting a respray I wasn't really bothered. I collected the car in early March and drove it home with my son for company.
Obligatory MaccyD on the way home!
First job was to sort the pedals out for better comfort and easy heel and toeing. These cars are joy to heel and toe but only after removing the accelerator pedal and bending it in a vice to get it closer to the brake. It's pretty easy, just remove the pedal box cover, disassemble the pedal to modify, then reverse the process.
I also took the opportunity to do a couple of minor bits in the engine bay, protecting cables etc and making sure it all worked properly.
About this time, I managed to go through the history folder properly. Every single invoice/mot/service sheet is there which is great for satisfying my OCD tendencies and chatting to the previous owner too was really helpful. It's million stonechips was explained by it being exclusively a track car but the upside is that it has been fastidiously maintained with a lot of money spent. So, through summer of 2018, I just drove it as much as I could (including one track day at Abingdon, forgot to take pictures though) and concentrated on getting to know it. Compared to my K Series R300, it's definitely faster and has got waaaay more mid-range torque, so gear selection for overtakes isn't so critical and it accelerates well. Handling seems as great, some people say the heavy Duratec blunts the front end, but I'm not good enough to tell and the setup already on the car ensured the front end was very pointy anyway.
Visit to Prescott Hill Climb with a mate in his 7:
Come winter 2018 it was tucked up in the garage ready for a bloody good service and springtime 2019......
Thanks fellas, I am quite keen on a tidy garage Chris, before all this C19 kicked off, I saw your Integra most mornings I did school drop off and follow your thread. Car's looking great!
To continue the story, over the winter myself and a mate took a full day to give it a service. The Caterham service schedule was followed to give it the 'big service' which is pretty lengthy. Unfortunately, this turned out to be a bit more involved than I thought! In order to start from a known point, I decided to change all the fluids on the car apart from the coolant (which would get changed later in the year so was just topped up) so engine oil, gearbox oil, diff oil, brake fluid, clutch fluid and spark plugs all got done.
The plugs were in good order, but got changed anyway.
I also took the opportunity to do a few little tidy up jobs like removing the flashing that could rub through the coil pack leads:
All 7s need the front stub bearings to be repacked with grease every 4 years and I suspected mine had not been done since it was built so this was also completed. Pretty straight forward to do, just remove the front caliper (AP 4 pots in this case which are very powerful on a 500kg car ) as well as the discs and the races.
Then with a bit of Comma's finest bearing grease, pack the races and reassemble.
I then moved on to the back of the car which took way longer than I thought. First job was a good clean to hammerite the areas of the chassis which had suffered from stone chips. The rear anti roll bar was repainted and treated to new bushes and the Bilstein shocks were disassembled and tidied up.
Repainted springs and thoroughly cleaned:
Next, the rubber boots on the rear brakes were replaced (old, scabby ones pictured) and the handbrake cable P-clipped to the chassis legs to prevent it rubbing and chaffing the cable shroud. This is a pig of a job, really fiddly and I'm getting far too old for laying on a cold garage floor in the winter on my back! In the end, patience and swearing prevailed and it's much tidier and safer than before.
Next, was the rear drop links. These are a pain the arse, they don't last long at all and end up being an advisory on virtually every MOT. My mate suggested I do what he does to his, which is to dissemble them and pack the ball cups with bearing grease. This makes them last about 4 years rather than 1 and tightens the rear end up by reducing the play. The old ones came out with tonnes of play and looked like this:
I simply removed the retaining clip, packed them with grease and re-assembled before fitting them back on the car:
All back together and with 2 new rear tyres:
At this point, spring was rapidly approaching and having had an aeroscreen on my last car, I decided I had to get one fitted. They're expensive but the experience is absolutely amazing so it had to be done. It really makes a difference to the feel of the car, it makes the sensation of speed so much more extreme which is especially great on the road for staying legal(ish) and having fun. It also increases the acceleration and the way the car brakes due to removing some of the drag from the car.
Unfortunately though, they're not fit and forget so you have to be brave and fit the mirrors yourself
First job was to test fit and mark out the positions of the mirrors (measure lots, cut once etc). Then throw any thoughts of ruining £700 of carbon out the window and crack on.
Once this was done, I bought a cheap plate for it, taxed it and got it back out on the road and on track. All the work was well worthwhile, the car felt amazing and is everything I love about driving, really raw and unfiltered. I also find I enjoy driving much more knowing all the little jobs are done and it's unlikely to let me down!
Chris, before all this C19 kicked off, I saw your Integra most mornings I did school drop off and follow your thread. Car's looking great!To continue the story, over the winter myself and a mate took a full day to give it a service. The Caterham service schedule was followed to give it the 'big service' which is pretty lengthy. Unfortunately, this turned out to be a bit more involved than I thought! In order to start from a known point, I decided to change all the fluids on the car apart from the coolant (which would get changed later in the year so was just topped up) so engine oil, gearbox oil, diff oil, brake fluid, clutch fluid and spark plugs all got done.
The plugs were in good order, but got changed anyway.
I also took the opportunity to do a few little tidy up jobs like removing the flashing that could rub through the coil pack leads:
All 7s need the front stub bearings to be repacked with grease every 4 years and I suspected mine had not been done since it was built so this was also completed. Pretty straight forward to do, just remove the front caliper (AP 4 pots in this case which are very powerful on a 500kg car
) as well as the discs and the races.Then with a bit of Comma's finest bearing grease, pack the races and reassemble.
I then moved on to the back of the car which took way longer than I thought. First job was a good clean to hammerite the areas of the chassis which had suffered from stone chips. The rear anti roll bar was repainted and treated to new bushes and the Bilstein shocks were disassembled and tidied up.
Repainted springs and thoroughly cleaned:
Next, the rubber boots on the rear brakes were replaced (old, scabby ones pictured) and the handbrake cable P-clipped to the chassis legs to prevent it rubbing and chaffing the cable shroud. This is a pig of a job, really fiddly and I'm getting far too old for laying on a cold garage floor in the winter on my back! In the end, patience and swearing prevailed and it's much tidier and safer than before.
Next, was the rear drop links. These are a pain the arse, they don't last long at all and end up being an advisory on virtually every MOT. My mate suggested I do what he does to his, which is to dissemble them and pack the ball cups with bearing grease. This makes them last about 4 years rather than 1 and tightens the rear end up by reducing the play. The old ones came out with tonnes of play and looked like this:
I simply removed the retaining clip, packed them with grease and re-assembled before fitting them back on the car:
All back together and with 2 new rear tyres:
At this point, spring was rapidly approaching and having had an aeroscreen on my last car, I decided I had to get one fitted. They're expensive but the experience is absolutely amazing so it had to be done. It really makes a difference to the feel of the car, it makes the sensation of speed so much more extreme which is especially great on the road for staying legal(ish) and having fun. It also increases the acceleration and the way the car brakes due to removing some of the drag from the car.
Unfortunately though, they're not fit and forget so you have to be brave and fit the mirrors yourself
First job was to test fit and mark out the positions of the mirrors (measure lots, cut once etc). Then throw any thoughts of ruining £700 of carbon out the window and crack on.Once this was done, I bought a cheap plate for it, taxed it and got it back out on the road and on track. All the work was well worthwhile, the car felt amazing and is everything I love about driving, really raw and unfiltered. I also find I enjoy driving much more knowing all the little jobs are done and it's unlikely to let me down!
Thanks gents 
My last K Series Caterham was dry sumped. Despite the Ford Duratec having a much better sump and oil system, it was always something I wanted to do with this car as I intend to track it and it allows me to use Avon ZZR (rather than ZZS) and not worry about blowing the motor up! During last year I kicked the idea around of doing it myself but ultimately decided my new job commitments weren't going to allow it. Mrs GP also wasn't keen about the amount of time it would take so it was booked in to Williams Caterham near Bristol to be fitted.
The dry sump kit is Caterham supplied and fitted. It's different to the K Series system (which uses a belt driven scavenge pump) in that the scavenge pump is internal to the sump and the oil tank is up front, rather than in front of the passenger footwell. Cost is £2700 fitted but it's cheaper than an engine rebuild
The car was dropped off at Williams in September and came back about 3 weeks later. The work was first rate and I'd definitely recommend them.
As expected the oil pressure was now rock steady in the corners and under hard braking. An added bonus is that the sump is shallower than the old wet sump so whacking it on speed humps is less of an issue! Servicing should be easier now too as I can just suck the oil straight out of the tank, although I believe there's 9-10 litres to go back in
Next up was the bit I was really looking forward to, the respray.
After a lot of research I decided to get PJA Coachworks near Heathrow to paint the car. Not only were they experienced in painting Caterhams, their reviews were excellent and I had previously test driven a car they'd painted so could see first hand the standard of their work. The car was booked in for October 2019, now all I had to do was decide on the colour......I had originally decided on Porsche Birch Green. I'd seen another 7 in that colour at Prescott and it looked stunning.
However, my son kept nagging me that it wasn't right and reminded me how good Renault Liquid Yellow looked. About the same time, this picture appeared on a Caterham press release and the decision was made!
The car was dropped off at PJA and I took home the exhaust and the rollbar taken home for tidying up. Whilst PJA got on with the painting, I had the exhaust and headers professionally polished, the rollbar and various suspension bits blasted and repowdercoated and ordered new carbon front arches and stoneguards, and the sticker set. I also arranged for a full set of PPF to be fitted by Dave at PPG Ltd.
The new side stripes and bonnet stripes were put on at and build continued.
Collection Day
I caught the train over to collect it and wow, what a transformation
I cannot recommend PJA enough, the paint finish was absolutely first rate and the way the Renault Liquid Yellow changes colour in the sunlight is nothing short of amazing. With the new carbon, repowdercoated rollbar and suspension it looked brand new. Super happy!
The drive home was great fun, except for the fact the battery (original Banner) was knackered and I had to be jump started at PJA. There wasn't much fuel in the car so I had to nurse it home on fumes, if I'd stopped to fill it up, it never would have started again All good though and it was tucked up at home in the garage under the new car cover.
My last K Series Caterham was dry sumped. Despite the Ford Duratec having a much better sump and oil system, it was always something I wanted to do with this car as I intend to track it and it allows me to use Avon ZZR (rather than ZZS) and not worry about blowing the motor up! During last year I kicked the idea around of doing it myself but ultimately decided my new job commitments weren't going to allow it. Mrs GP also wasn't keen about the amount of time it would take so it was booked in to Williams Caterham near Bristol to be fitted.
The dry sump kit is Caterham supplied and fitted. It's different to the K Series system (which uses a belt driven scavenge pump) in that the scavenge pump is internal to the sump and the oil tank is up front, rather than in front of the passenger footwell. Cost is £2700 fitted but it's cheaper than an engine rebuild
The car was dropped off at Williams in September and came back about 3 weeks later. The work was first rate and I'd definitely recommend them.
As expected the oil pressure was now rock steady in the corners and under hard braking. An added bonus is that the sump is shallower than the old wet sump so whacking it on speed humps is less of an issue! Servicing should be easier now too as I can just suck the oil straight out of the tank, although I believe there's 9-10 litres to go back in
Next up was the bit I was really looking forward to, the respray.
After a lot of research I decided to get PJA Coachworks near Heathrow to paint the car. Not only were they experienced in painting Caterhams, their reviews were excellent and I had previously test driven a car they'd painted so could see first hand the standard of their work. The car was booked in for October 2019, now all I had to do was decide on the colour......I had originally decided on Porsche Birch Green. I'd seen another 7 in that colour at Prescott and it looked stunning.
However, my son kept nagging me that it wasn't right and reminded me how good Renault Liquid Yellow looked. About the same time, this picture appeared on a Caterham press release and the decision was made!
The car was dropped off at PJA and I took home the exhaust and the rollbar taken home for tidying up. Whilst PJA got on with the painting, I had the exhaust and headers professionally polished, the rollbar and various suspension bits blasted and repowdercoated and ordered new carbon front arches and stoneguards, and the sticker set. I also arranged for a full set of PPF to be fitted by Dave at PPG Ltd.
The new side stripes and bonnet stripes were put on at and build continued.
Collection Day
I caught the train over to collect it and wow, what a transformation
I cannot recommend PJA enough, the paint finish was absolutely first rate and the way the Renault Liquid Yellow changes colour in the sunlight is nothing short of amazing. With the new carbon, repowdercoated rollbar and suspension it looked brand new. Super happy! The drive home was great fun, except for the fact the battery (original Banner) was knackered and I had to be jump started at PJA. There wasn't much fuel in the car so I had to nurse it home on fumes, if I'd stopped to fill it up, it never would have started again
All good though and it was tucked up at home in the garage under the new car cover.Wow, wow, wow!! Great choice going for Liquid Yellow! I had a Clio 200 in the same colour and it is stunning. (Bit of a nightmare to colour match the inevitable stone chips though).
Very jealous of that garage, I’d happily live in there! I’m I right in thinking you ran a Racing Blue Clio 182 alongside your S1 Elise? If so, you have excellent taste, and very similar to mine!
Very jealous of that garage, I’d happily live in there! I’m I right in thinking you ran a Racing Blue Clio 182 alongside your S1 Elise? If so, you have excellent taste, and very similar to mine!
RM10 said:
That paint job, wow!
Can I ask, what is it like driving on normal roads with the aero screen compared to the normal windscreen? Do you feel a lot more pressure on your face, and what's it like at 60-70mph?
Thank you! The aeroscreen is great, I wear a baseball cap, ballistic rated sunglasses (got issued them when I was in the military) and a black buff that I can pull over my mouth to stop flies and stones and it works great. It's pretty a visceral experience but at speed there's no pressure on my face and it's very comfortable. I do wear ear plugs though as the wind and exhaust noise are pretty fearsome!Can I ask, what is it like driving on normal roads with the aero screen compared to the normal windscreen? Do you feel a lot more pressure on your face, and what's it like at 60-70mph?
HotHatchFan said:
Wow, wow, wow!! Great choice going for Liquid Yellow! I had a Clio 200 in the same colour and it is stunning. (Bit of a nightmare to colour match the inevitable stone chips though).
Very jealous of that garage, I’d happily live in there! I’m I right in thinking you ran a Racing Blue Clio 182 alongside your S1 Elise? If so, you have excellent taste, and very similar to mine!
It's a great colour and I'm glad I went for it! The car has had the full PPF treatment (nosecone, bonnet, sides, rear arches etc) so should hopefully stand up to most stone chips. It's the self healing stuff too and is working great so far. I was warned by PJA that touching up the Liquid Yellow was a total nightmare, so it was a must really.Very jealous of that garage, I’d happily live in there! I’m I right in thinking you ran a Racing Blue Clio 182 alongside your S1 Elise? If so, you have excellent taste, and very similar to mine!
You're quite correct about my Racing Blue Clio 182 and my Norfolk Mustard Elise S1
I really miss both of those cars and if I could have kept them both I would have done. Sadly space, finances and a wife that declared 'we are NOT a 4 car family!' put paid to that 
After the respray and over the winter a few mundane but important jobs were done. First up was the rubber surrounds for the instrument dials. Being open to the elements and sunshine makes them deteriorate quite quickly meaning they crack then fall off and then the instrument rotates to odd angles with the engine vibration
New ones purchased from Chris at Redline (great service as ever) and instruments reset to the the right way up.
Stone chips are a bit of an issue on a 7 and especially underneath and down the sides of the lowered floors. Mine is pretty good but keeping on top of it is essential to stop corrosion on the chassis bars where the powdercoat can chip off exposing the steel. So out came the Satin Hammerite and then a liberal coating of ACF50 to finish things off. At the same time I had the seat rails fitted with captive nuts to enable to the bolts to go up through the chassis rather than down which helps with grounding over speed humps. All finished off with black countersunk washers from Probolt.
New ones purchased from Chris at Redline (great service as ever) and instruments reset to the the right way up.
Stone chips are a bit of an issue on a 7 and especially underneath and down the sides of the lowered floors. Mine is pretty good but keeping on top of it is essential to stop corrosion on the chassis bars where the powdercoat can chip off exposing the steel. So out came the Satin Hammerite and then a liberal coating of ACF50 to finish things off. At the same time I had the seat rails fitted with captive nuts to enable to the bolts to go up through the chassis rather than down which helps with grounding over speed humps. All finished off with black countersunk washers from Probolt.
DoubleD said:
It looks really stunning in that colour. Is it costly to change the colour?
It was just over £3k but that was a drive in, drive out cost with loads of extras added on by me, so I thought it was a very reasonable price. I'm incredibly fussy about paint finish and attention to detail and PJA did a superb job.Continuing the winter work on the car, I also took the opportunity to sort out interior a bit. I purchased a new black metal anodised gearknob to replace the mismatched silver one and also a new black metal anodised handbrake cover to replace the horrible plastic one. Granted neither are strictly necessary but they lift the cabin a bit and look miles better.
Out came the seat again (I'm getting really good at it now!) and I fitted the required bits to upgrade the driver's side harness from a 4 point to a 6 point. I had read loads about 'submarining' in an accident (slipping down under the belts) and as I intend to track the car a fair bit, it makes sense to make it as safe as possible. Great service from Steve and Ben at Corbeau who not only supplied all the bits for a great price but also rebuilt the buckle mechanism with a new handle and new cover stickers. The extra straps fit to the back of the chassis on pre-welded lugs with eye bolts and nyloc nuts so it's a very straight forward job. I adjusted it to length to suit then popped the seat back in with the newly rebuilt harness box fitted at the same time.
Next up was the boot. It was just bare mental inside and open to the road due to gaps between the sideskin and the floor, meaning all sorts of s
te found it's way in. This coupled with my need to put stuff in there for trackdays (and my need to have it looking neat and tidy ) meant padding and carpet had to be fitted. The carpet was bought off ebay and then a template made up and the carpet cut. 'Soft Bits' padded boot liners were then added to the sides to finish it off. 
This brings things up to a few weeks ago when lockdown started to ease, which meant the last big job of getting the geometry done could be completed. I took the car down to DPR Motorsport near Gatwick and had them set it up since they seem to have the best reputation and set up most of the Caterham Motorsport cars. I had a brilliant morning, watching Andre work on the car and chatting to David, the owner.
The car had a very aggressive, track based set up on which was optimised for Avon ZZR semi slick and/or slick tyres. This was ok for me as I like that sort of setup but the tyre wear was insane (possibly exacerbated by my driving style
) so I wanted it dialled back slightly, especially since I use the car on the road as well as track and prefer Avon ZZS tyres. They did an excellent job, including shimming the de Dion tube to ensure the rear toe and camber were accurate and I'm really happy with the results. At the same time I got them to fit some Jack Webb Motorsport top mounts so I can easily adjust the front camber myself in future.If anyone's interested in the settings, I went for -1.6 camber on the front with 1mm toe out (I like a pointy front end) and -1.5 camber with 2mm toe in on the rear. Rake was set to 19mm. It's still quite rear biased and pointy which makes it superb fun to drive
That really takes things to the present day and I can now enjoy it on the road and on track for the rest of the summer. All the major things I wanted to achieve and change are now done and as a car to remind you what the thrill of driving is like, it's second to none. I absolutely love it and really think everyone should have a go of a fast Caterham at least once in their life!
Finally, if anyone's going to the Abingdon track day in a couple of weeks on 17th July pop over and say hello
Update on the Caterham, it's not particularly exciting though so apologies for that
Over the winter, I've been chipping away at the service and a few small maintenance jobs in order to get the car ready for a few track days in 2021. According to the schedule, this year is a bit more lengthy than last year, so aside from the usual oil change and filter, spanner check and inspection, the brake fluid and clutch fluid were changed and the systems bled. This year is the first year my son is tall enough to reach the pedals so he was roped in to help, rather than Mrs GP who is always enthusiastic about sitting in a cold garage messing about with cars
The coolant and gearbox oil levels were checked and topped up as was the diff oil. Whilst I had the car in the air, I thought I'd quickly check the Titan LSD. The Titan is a clutch plate LSD so this involves turning one wheel and making sure the other wheel goes the same way (unlike an open diff where it'll rotate the opposite way).
Alarm bells started ringing when the other wheel stayed stationary, so I checked the preload. This involves measuring the torque needed to turn one wheel while the other is stationary. One rear wheel has to stay on the ground and other has to come off, the handbrake stays off and the car is put in neutral. You then take the torque wrench and using a 41mm socket over the hub nut, incrementally measure the torque required to turn the driveshaft.
A new, fresh diff from the factory should measure 40 lb ft (or slightly more) and this will reduce as the clutches wear. At 20 lb ft or less the diff is more or less knackered and needs a rebuild. Mine measured 17-18 lb ft
A bit of research on tinterweb showed the diff plates got changed to carbon faced clutch plates around the time my car was built, rather than sintered plates, in an effort to reduce noise and vibration. They then got changed back to sintered in around 2016 for reasons I can only assume are linked to the carbon plates wearing out too quickly and generally being a bit st.
This was obviously pretty rubbish news and not really expected at 15k miles so the next step was to drop the diff oil and see what colour it was. Straw coloured would be good and black would bad, showing that all the carbon was in the oil and not on the clutch plates. So, out it came and looked like this:
Oh bks! Running it through my fingers, it felt like grinding paste and was obviously full of carbon Whilst I mulled over what to do about it, I set on getting the diff out the car for the impending rebuild. This is something I've never done before so instead of the 3-4 hours it should take, it took over 5...
I elected to make things a bit more tricky than necessary by removing the hub nuts and hubs to get to the rear wheel bearings. Usually this isn't necessary but Caterham changed the rear wheel bearings to a 'sealed for life' design a few years ago, so while I'm taking it all apart, I figured I'd change them now and not have to worry about re-greasing the old ones in the future.
Typically, one hub nut came off fine, the other one broke the breaker bar
It was obvious it had been overtightened from the torque marks as they didn't line up at all:
Despite a new, beefier bar being obtained from Halfords (free of charge due to the lifetime warranty ) it simply would not budge with plusgas, heat or scoffold pole over the bar. Luckily a request for help on our local FB page was answered by a very kind chap who drove over with an impact driver and whizzed it straight off. I was genuinely humbled at this and hugely grateful.
The dismantling from then on wasn't particularly tricky, just time consuming. I laid everything out neatly in a effort to make it easier to reassemble and eventually out the diff came despite it being bloody heavy and quite awkward!
Now is the long wait for the diff to come back. I've elected to put an SPC Tracsport diff in rather than another Titan and it should be here in 3-4 weeks. Fingers crossed the car will be back on the road in April!
Over the winter, I've been chipping away at the service and a few small maintenance jobs in order to get the car ready for a few track days in 2021. According to the schedule, this year is a bit more lengthy than last year, so aside from the usual oil change and filter, spanner check and inspection, the brake fluid and clutch fluid were changed and the systems bled. This year is the first year my son is tall enough to reach the pedals so he was roped in to help, rather than Mrs GP who is always enthusiastic about sitting in a cold garage messing about with cars
The coolant and gearbox oil levels were checked and topped up as was the diff oil. Whilst I had the car in the air, I thought I'd quickly check the Titan LSD. The Titan is a clutch plate LSD so this involves turning one wheel and making sure the other wheel goes the same way (unlike an open diff where it'll rotate the opposite way).
Alarm bells started ringing when the other wheel stayed stationary, so I checked the preload. This involves measuring the torque needed to turn one wheel while the other is stationary. One rear wheel has to stay on the ground and other has to come off, the handbrake stays off and the car is put in neutral. You then take the torque wrench and using a 41mm socket over the hub nut, incrementally measure the torque required to turn the driveshaft.
A new, fresh diff from the factory should measure 40 lb ft (or slightly more) and this will reduce as the clutches wear. At 20 lb ft or less the diff is more or less knackered and needs a rebuild. Mine measured 17-18 lb ft
A bit of research on tinterweb showed the diff plates got changed to carbon faced clutch plates around the time my car was built, rather than sintered plates, in an effort to reduce noise and vibration. They then got changed back to sintered in around 2016 for reasons I can only assume are linked to the carbon plates wearing out too quickly and generally being a bit s
t.This was obviously pretty rubbish news and not really expected at 15k miles so the next step was to drop the diff oil and see what colour it was. Straw coloured would be good and black would bad, showing that all the carbon was in the oil and not on the clutch plates. So, out it came and looked like this:
Oh b
ks! Running it through my fingers, it felt like grinding paste and was obviously full of carbon Whilst I mulled over what to do about it, I set on getting the diff out the car for the impending rebuild. This is something I've never done before so instead of the 3-4 hours it should take, it took over 5...I elected to make things a bit more tricky than necessary by removing the hub nuts and hubs to get to the rear wheel bearings. Usually this isn't necessary but Caterham changed the rear wheel bearings to a 'sealed for life' design a few years ago, so while I'm taking it all apart, I figured I'd change them now and not have to worry about re-greasing the old ones in the future.
Typically, one hub nut came off fine, the other one broke the breaker bar
It was obvious it had been overtightened from the torque marks as they didn't line up at all:
Despite a new, beefier bar being obtained from Halfords (free of charge due to the lifetime warranty
) it simply would not budge with plusgas, heat or scoffold pole over the bar. Luckily a request for help on our local FB page was answered by a very kind chap who drove over with an impact driver and whizzed it straight off. I was genuinely humbled at this and hugely grateful. The dismantling from then on wasn't particularly tricky, just time consuming. I laid everything out neatly in a effort to make it easier to reassemble and eventually out the diff came despite it being bloody heavy and quite awkward!
Now is the long wait for the diff to come back. I've elected to put an SPC Tracsport diff in rather than another Titan and it should be here in 3-4 weeks. Fingers crossed the car will be back on the road in April!
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