Jonathan Kay

I am curious as to why given the voltage readings the power dropped off after only five quick turns... The unloaded voltage of typical car batteries drops very little as they go flat or even fail. There are dedicated load testers, but in practice the extreme load of trying to crank works well. That's why I rabbit on about measuring the minimum voltage during cranking. (As well as the issue about electronic bits dropping out.) ... one thing I forgot to mention is that between attempts to start it the ignition light had a slight flicker. Flicker when the alternator isn't turning and the light should be fully on? That's showing a low voltage at rest (or a problem with the wiring or connections). But I'm surprised it happened with your observed voltages. I don't think we can tell yet whether the current battery has any worthwhile future. But if it's topped up and the connections are OK I'd like to see the whole thing start nicely when jumped, and also check that the car's charging system is working by measuring the battery voltage at 3,000 rpm. When you've had a chance to identify the charger, principally to discover whether it's a traditional charger or a sensing conditioning charger, we can do some quick checks on that. Jonathan

What sort of battery, and is it the sort you can top up? What sort of charger? Can you jump it off another battery? it's probably worth inspecting and cleaning all the relevant wires and connections: the fat ones to the starter and alternator, the engine earths, and everything at the battery terminals. Jonathan

I'd keep an eye on that minimum voltage while cranking. It's probably the first indicator of pining for the fjords Jonathan

Thanks. I'm suspicious about what happens to electronics on 7s when the voltage drops below 10.5V, especially ECUs and immobilisers. The battery might be on the way out. Jonathan

Welcome. It's pretty easy to change seats and belts yourself, and there's lots of help available here. No special tools needed. There's a notorious problem with the floor bolts but there is also a range of simple solutions. Are you sure you don't want a crotch strap, at least on the driver's side? Are you set on Caterham harnesses? The last replacement I did was with Titon and I was very pleased. They'll make the adjuster work either way, and I wanted down and away on the lap straps. I bought them from Prima, but If I were doing it again I'd start with Meteor. Jonathan

Well done. Can I persuade you to run the voltage checks on it now that you've got control: engine off, minimum during cranking and 3,000 rpm? I know I committed a cardinal sin of diagnosis in changing more than one thing simultaneously... ;-) Jonathan

It sounded low to me. That was from the 1998 Guide. Previous discussion: check the top two threads. But I've never not had enough with a 5 L bottle. Jonathan

"Approximately 6 pints" according to the Assembly Guide. 6 pints ≈ 3.4 L Jonathan

Glad it's fixed. I went back to caterham cars and they said " I don't know how we missed that" Hmmm... are you going to talk to PGM as well? Jonathan

I can see some blogs here, including one from yesterday. And some images here (didn't know that existed). (Safari, macOS.) Jonathan

Didn't we once identify the part number of an identical Ford branded product? Jonathan

Ask the supplier for free samples? Jonathan

34 Nm according to the Assembly Guide. Jonathan

Don't forget to record the evidence with that app. Jonathan

The Road Vehicles Lighting Regulations 1989, but it's not always easy to be sure it's current. I'd think of the legality in two parts: The lights. If you pass the deceleration signal to the existing legal lights there's no issue. If you use additional lights they'd have to comply. The manner of activation. I can't see a problem with the Regulations... except that if you use additional lights and classify them as stop lights you'd have problems with 10 a ii.Jonathan

I'll post the photo when I work out how to do that Forum User Guide Jonathan

This is the Security section of the current handbook. Same as your immobiliser? Same document you've already got? Jonathan ... Security Keys/key numbers You have been supplied with 4 keys: 2 for the ignition and 2 for the fuel cap. The numbers for these can be found on a small tag attached to the key ring. You will also have been supplied with 2 coded transponder tags. WARNING! Keep the key tag and spare key in a safe place – NOT IN THE CAR! If the key or tag is lost please contact Caterham Cars to make arrangements for a additional keys and tags. Immobilisation Most Caterhams are fitted with an immobiliser as standard, this will be Sterling Excel vehicle immobiliser system. Disarming the system Insert your ignition key with the transponder unit attached to the same key ring and the reader unit will automatically recognise the transponder and disarm your immobiliser. The LED will stop flashing and turn a constant red indicating the vehicle can be started Arming the system When the vehicle’s ignition is switched off and the keys are removed from the ignition, the immobiliser will prepare to arm and the red LED will illuminate. During this period, the ignition can be switched back on, cancelling the arming and permitting the vehicle to be started as normal. If after twenty seconds the ignition has not been turned on, then the immobiliser will automatically ‘arm’ and the red LED will flash. This ‘auto-arming’ sequence means that it is impossible to leave your vehicle unprotected. [​WARNING! Your system will automatically re-arm within twenty seconds of disarming if you do not turn the ignition on. Programming new transponder tags If you require a new transponder tag for an additional user, or as a replacement through loss or damage, please contact Caterham Aftersales Department. Once you have received your new transponder tag, you will need to programme it. To do this you must have an existing transponder tag that already operates the system. 1) Disarm the system using an existing transponder tag attached to the ignition key. 2) Switch the ignition on and off twice and then turn the ignition back on, all within 7 seconds (the LED will flash rapidly). 3) The system will then recognise the transponder tag on the key ring and re-programme it. 4) The LED will flash once to indicate it recognises the transponder tag. 5) Remove the ignition key with the transponder tag attached. 6) Pass a new transponder tag close to the ignition barrel. 7) The LED will flash twice to indicate that the new transponder tag is in the memory. 8) Pass any additional transponder tag close to the ignition barrel. 9) For each transponder tag programmed into the system the LED will flash a number of times to indicate how many transponder tags are programmed into the system. 10) When you have finished, switch the ignition off and the Sterling Excel will exit the programming mode. Each time you programme a new transponder tags into the system it will automatically erase all other transponder tags in the memory therefore all transponder tags required to operate the system must be programmed back in. NOTE: For EU4 cars the transponder is in the key, if you require a new transponder as a replacement through loss or damage please contact your local ford dealer. Deleting lost transponder tags from the system memory If you lose one of your transponder tags, your vehicle is no longer totally secure, as anyone who finds your lost transponder tag could disarm your immobiliser. To prevent this from happening you are able to delete transponder tags from the system. Because your Sterling Excel system will recognise up to five different transponder tags, you will have to re- programme all of your existing transponder tags every time you enter programming mode. NOTE: Sterling Excel is an electronic immobiliser and derives its main power from your car battery. However, the consumption in the armed state is such that it should not adversely affect your car battery. WARNING! The tags contain delicate electronic circuits and must be protected from impact and water damage, high temperatures and humidity, direct sunlight, effects of solvents, waxes and abrasive cleaners. Vehicle battery disconnection If the car battery is disconnected for any reason the status of the security system prior to disconnection will be memorised and automatically reset when the battery is reconnected.

I've got some documents, but we need to work out what yours is called. How many buttons and does it have a battery in the fob? Can you add a photo? Jonathan

What temperature thermostat are you using? Does the fan come on when needed and not otherwise? You've replaced the radiator and split hose and the expansion bottle cap. Are you sure you have the right sort of cap? Please add a photo if not. Beyond those failed bits I'm not sure I'd suspect anything beyond the dreaded air lock. You have a heater and you're lifting the nose. Do you have a bleeding T-piece? Does the thermostat have the extra hole? Jonathan

Have you got the reset procedure for your type of immobiliser? Jonathan

Look what happened once Uncle Albert asked questions like that... I'm guessing, but the answer may be that they have gyroscopes as well as accelerometers. Jonathan

Without wanting to sound stupid... How does an inertia switch differentiate between inertia and the car being at an angle on a hill? You're not. Jonathan

Didn't know they existed, but it has been suggested that the deceleration from the massive drag is so high that something like that would help. And accelerometers are very cheap now because of smart 'phones. Sounds good. Would it be better to drive the existing brake lights? Review of the Ohmics light system. Jonathan PS: My touring human powered bike now has something similar: the rear light flashes when the bike decelerates. But it isn't driven by the deceleration...

Quick summary of the previous discussions: Don't use stuff to block it. No need for a Caterham specialist: talk to a local repairer ... who will pressure test it before returning it to you.Jonathan

Welcome Jonathan