Temp sensor - error solved

Still learning ...

Last time I fiddled with the ECU, I was very satisfied with the settings I found. My disappointment was even greater when the engine didn't start last Saturday. Although the engine was cold, the fan ran immediately. I connected the tablet only to read 80°C coolant temp. Out came the multimeter to check the sensor, but it was ok. What else could it be? *scratching head* ...

The Emerald ECU has some features to prevent engine damage. One is to monitor the coolant sensor and switch the fan on regardless of a short or a loose connector. Therefore you can set the above/below thresholds in the coolant sensor calibration menu. A loose connector gives 5.0V, a short will give 0.0V, the settings should then cover everything in between -30°C and +120°C (see graph). My settings were a touch too optimistic with 0.9 and 3.9. The default settings from Emerald are as above, but you still can enter user defined values.

With the adapted values, the error disappeared and the car started. Happy again!

Cheers.

Coolant fill

The new radiator also meant that most of the coolant was lost during the crash and the change. Without the scuttle where the nice aluminium expansion tank is fixed, I mounted the old one on top of the engine and filled the circuit via the thermostat housing. Once the liquid spills out of the small radiator port, it has to be closed, then the thermostat housing is filled to level and also closed. The expansion tank is then filled a little above minimum and closed. Time to look around the whole circuit for leaks. When the engine gets started and the coolant circuit is under pressure, there might appear some drops on connections and it will be fixed. For now it's good to know that the coolant is in again. One more step done before restart.
Cheers.

Water cooler

The (new) Caterham water cooler is very lightweight. It is mounted through vibration dampers to the chassis. The old water cooler was damaged beyond repair during the crash.

The Samco piping can be reused which makes for some money saving.

The Pacet fan was broken as well and has been replaced by exactly the same item purchased together with the water cooler. Luckily I kept the wrecked fan and now reused the clips to fix it to the cooler (no clips provided). The overflow will be connected when the bulkhead is ready to receive the expansion tank.
Cheers.

Water cooling circuit

As assembly progresses (well, sort of), some theory worse to be spread about the plumbing. Let's start with the water cooling circuit. Starting with a layout lent in a german forum, I adapted it to what will be found in my car once completed (ex the water temperature gauge which will be integrated into the digital Stack dash). Quite a basic setup without a heater, hence the missing pipes and valves. Note the two separate temperature sensors, one for the stack gauge and one for the Emerald ECU. There are two ways to switch the fan once a set temperature has been reached:
1) via the temperature switch (mechanical / bi-metal) in the thermostat housing, fixed value
or
2) via the ECU where the switching temperature can be set as wished.
Cheers.