Cooling problems again

 On my last trip I almost overheated again.   When I checked, the overflow bottle I have fitted was almost full.  And putting that back into the expansion bottle brought the level back up.   So I don't have a leak anymore, it's being dumped via the pressure cap on the expansion bottle.

So either the pressure cap is faulty, the seal between the cap and the bottle is dodgy, or the cooling system is over pressurising.  The cap is 20psi, so I don't think it is the third option.  As a first step I will buy a new cap at 22psi and see if that helps.  If it doesn't help then I will have to replace the expansion bottle.   I do have a spare, but swapping them is not a trivial task.

Watch this space.

Static Test (6) - Alternator

My program also tracks the battery voltage (actually the alternator voltage when the engine is running)   The voltmeter I have in the car indicates about 14.2V, although the ECU reckons it is 13.7V.   It’s perhaps a bit on the low side, but is still well within the normal range so not worried about that.

Static Test (5) - Lambda Sensor

One of the most important checks is the lambda sensor.   You will have seen from previous posts that this is a sore point on the Superspec.  I’m pleased to report that mine continues to work perfectly.  The pictures show the whole 20 minutes and a snap shot of a 2 min segment.   It’s a fairly crude system that we used to call the ‘bang-bang’ method (maybe they still do?).  Rather than try and stabilise the fuel/air ratio it goes from rich to lean in a very fast cycle so that over time the average mixture is correct.