ChrisC

Yep - I have one as well.   Easy low enough to get under the A frame mount on the dedion tube with 13" and CR500's, can't see you needing anything lower than that 

Only criticism I can give is when new it was difficult (but not impossible) to lower the car very slowly, this seems to have become easier over the years. 

What time did you get?

I just unwound the spring seats mostly by hand, guess thats the benefit of adjustable platforms.    Sounds like I got it easy for once. 

I did it a few years ago when I converted a car to wide track.   I was expecting it to be a mission, but it was actual very straight forward.   Removed the spring, removed the mounting end, add the extent ion and reassembled.   From memory there is a nut that locks the mount to the shaft, so it's simple to remove.  I had concerns how I was going to hold it without damage.   Don't know a torque setting, but loctite seems like a good idea, you will be able to see if some has been.

Why do you rule out repair?  Caerbont do repairs, not sure how much or how long they take, then again it might be a loss of driving time / cost equation your working on.

Glad you sorted it, shame it a £180 part, but thankfully it isn't the pump at £420 

Agreed but that comes from temperature compensation, i.e. 10% extra because the temperature is X degrees.    Problem is my cars ECU is seeing a higher temperature, so the fuel compensation is wrong.    In my case the fans run all the time, because the ECU is seeing a hotter coolant than the gauge (which uses a different sensor) is seeing or my IR temp gun is reading.    

I suspect your problem is not the same as mine, but I just wanted to see if your fans where running all the time to see if your ECU was not recognising how cold the engine is.  

Does your fan run early?    Another minor problem my car has is the coolant temperature reading in the ECU is higher that the measured temperature,  My ECU sees 96+ degrees, but the IR temp gun can't get temperatures over 80.   So my fan runs before the thermostat opens or the rad is even warm.   I can either replace the stat with an 82 degree stat or try to get the coolant sensor recalibrated.    I can't remember seeing a "cold map", just compensation for the coolant and lamda.   If the coolant is under 60 lamda isn't used, but if the coolant is over reading this will be lower and the compensation for temp will be incorrect, resulting in poor cool running.

A little gem I discovered this weekend about my R spec Tacho.   I have a 360R which I put on easymap to discover the Tacho was over reading. Easymap said 950 to 1000, but the Tacho reads 1150-1200.  If I dropped the revs based on the Tacho I would expect to have problems with the cold idle.

Assume if your talking to Derek is a new build, so all new parts.    It may be to late for my first comment, but here goes anyway, If you have a removable steering wheel, and intend for Caterham to do the IVA, don't bother with the top steering column bush.   It will be removed and refitted during the process, so save the effort.   When you do put it in, make sure the plastic insert is the correct way round.   If its incorrect it will push into the column tube as you fit the upper column.    Don't connect the lower column to the UJ until you have the upper and lower columns in place (not clamped), in fact don't have the UJ on the rack either for that extra bit of space.    Lube the columns inside on upper and outside on lower, and wiggle them as they slide.    My S3 had a little unused fixing hole and tang that just touched the lower column (in the pedal box), it was spotted during IVA and a simple bend of the unused fixing point solved the problem, but maybe this is causing your alignment problem?  Finally you could always remove the grommets from the cheese wedge to get that bit more wiggle room, but they may be a cow to refit. 

Agreed, I found that strange as well.  

What I find strange is the fuel pump unit not being CAN, i.e. the signal from the fuel level isn't CAN given that it's from a modern car. 

I have the tools to decode and debug the CAN bus, but it would have to be on a trail an error basis, i.e. I won't get the information from Caterham about what channels are being used, the only way to find the fuel signal is take snapshots from the CAN bus, then add fuel, take another snapshot and see what's changing. 

One final thing, the Tacho is also connected to the CAN signal from the ECU, its possible its putting out the fuel level onto the CAN bus.   I am no expert on CAN, but CA instruments on their web site say they have been working with Caterham on CAN instruments, and I know the 3/4 step gauges are CAN not resistance based.    Time to dig out my MBE lead and dig a bit I think.

I guess.  I can't find any information on the connections and what that Tacho does.  I thought it was doing voltage stabilisation, but that might be a bit old school for the wiring on a 2013 car.   Most of the connections make sense, because the Tacho also has warning lights, but I don't understand the fuel level connection being passed through the Tacho, unless it could have had a fuel warning light at some stage in the design, or for different markets.

So you now need to check you have 8.8 ohm on GB150 at the Tacho,  if you don't then the connection GB148,149 and 150 connection or the engine loom connection could be causing the problem.  If you do then the Tacho is not passing the signal onto the gauge on Y198.   

On the pump SG196 and B10 are both earths, all be it SG196 is a bit indirect.  YG168 is the pump +ve and GB148 is the fuel level sensor.  0.8 ohm between YG168 and earth (B10 or SG196) is the resistance of the pump and sounds about right to me.   Concentrate on GB148 and getting that 8.8 ohms to gauge to solve your problem.  

Based on what you have posted connection or Tacho is my guess now.  When it stopped working, was that before or after you applied 12v to the Y198 wire?  If it was before it stopped working I think your going to need to try swapping the Tacho out.

From the diagrams its not a simple connection between the sender and the gauge.   

Fuel Gauge 
G76     Connected To G74/77/78/79/80/81/82/83/85/171 
            G74 Connected To Instrument Fuse 
B27/28 Connected To B19/22/23/24/25/26/27
             Earth 6mm Eyelet (near wiper motor)
Y198     Connected To Tacho

Fuel Sender / Pump
YG168 Connected To Inertia Switch
            Connected to fuse and fuel pump relay
GB148 Connected To GB149/150 
            GB150 Connected To Tach 
            GB149 Connected To Engine Loom Plug (large) GB52 engine loom
            GB52 Engine Loom Connected To Chassis Loom Plug (small) Fit Blank 
SG198 Connected to Engine Loom Plug (large) BY51
            BY51 Engine Loom connected to Earth eyelet 6mm
B10      Connected To B 2/12/13/14/15/16/17 
            Connected To Earth 6mm Eyelet

So the signal wire for the gauge is Y198, if you connected it to 12v you are more likely to damage the Tacho than the sender.   The sender signal seems to come from GB148 on the pump unit, but it looks like there are possible areas where the signal could be lost, for example in its connection to GB150/149, the connection through the Tacho or via engine loom plugs in some way. 

I would use the engine loom plugs to see if the signal is there.   If it is, and its present at the Tacho on GB150, then the Tacho might not be passing the signal thought to the gauge for some reason.    

The Tacho and the sender pump units are expensive parts so swapping them just because is an expensive way to go, do you have anyone local with a similar spec car that's willing to help? 

Hope this helps

My 360R has a 6sp and I don't think it would take much provocation to loosen the backend, with 8" ZZSs on the road, 6" I bet wont last long.    Have a look at the Chris Harris Caterham Supersport R video on youtube, it has the same engine as the 360R and 6" on the rear, all be it on CR500s.    

If you want more sideways try the Caterham drift experience setup.  The car I drove was a Sigma, and  that car didn't want to go straight :-) at any speed.  From memory it had the following.

No front ARB, tight rear ARB, 6" rears with CR322 and I bet they where pumped up to explode and jacked up rear ride height.  

I was expecting a change to the rear calipers as well, but it looks like caterham (from the parts website) has got sierra rear calipers remanufactured in Taiwan since 2016 instead of using reconditioned units. 

It's a guess, but I suspect the change was to replace the standard hard to get triumph caliper with an off the shelf two pot AP caliper.   This also means both new calipers are standard AP calipers (obviously with caterham logos), so it might have reduced manufacturing costs as well.   The down side being the extra effort required for pad replacement.

I think if you want OMG in the straights its got to be a 620R.  The rest is just going to be marginal gains. 

Can't imagine its much larger, there isn't much space in the 13" wheel for anything larger, you already have to be careful where the wheel weights go.  But as you said they are grooved ;-)

Remove the original bolts, and replace with normal cap heads, and a more appropriate strength and quantity of thread lock. 

And the original bolts used to secure them to the uprights have caused a lot of owners problems to removing them.

Agreed - take out F and see if anything else stops working, and take out M and see what stops.  

I don't think it's weird, I think it's a shame changes are made and the documentation given to the owners / customers is not updated.    I have posted before that there are wires in my old Sigma cars loom that aren't in the wiring diagrams, and you car has CAN bus instruments, but that isn't shown in the wiring diagrams either. 

At this rate your going to have the complete list of 420R fuses mapped Marcus, but don't publish it, sell it back to Caterham  :-)

Found it http://www.caterhamr500.co.uk/2014/08/raceco-exhaust-fitting-and-noise-tests.html

it was indicators, so I guess unrelated, but strange how what seems like unrelated fuses can knock out a Duratec.

I may be wrong, but didn't The guy that does the R500 blog have a breakdown early on when the 7.5 fuse blow.  It's was something to do with the earth on the calliper from memory.  Might be worth checking out.

Thanks all, when I worked out it was induction related I expected it to be a case of TADTS.  I think I am going to change to a k&n panel, but keep the air box for now.  I want to find out what sort of drive by noise it's making before making any significant changes.   I have had a car that was always marginal on induction noise, and that was a real pain in the backside.