[paulgato]

It's been a busy winter so far - and a really, really, record-breakingly wet winter. The wettest January in the UK since records began 250 years ago. It has rained virtually every day and I have not felt like working under a car on my driveway, so all this was put on hold. Also, during one of the many storms we have had a tile fell off my roof onto my driveway so have not felt too comfortable about parking my car there by the house where I can plug it in to the mains power supply, in case another tile falls on it.

However, I did manage to fit a waterproof outdoor power socket on the wall of my house by my driveway, and also, crucially, I got around to getting rid of an old van that had been permanently parked on that driveway for the past 5 years and had been used as a storage shed. So now I have a space to park the car and a means of plugging it in to the mains overnight.

I still haven't got that engine pre-heater installed, but today I did fit the battery charger in the engine bay and sorted out a temporary way of plugging it in overnight. I disconnected the alternator field wire, so from tomorrow onwards I shall be running without the alternator for all normal daily driving, only switching the alternator back on for longer trips of more than about 150 miles.

I'm kind of regretting buying that expensive and rather complicated coolant heater. Monitoring more closely the mpg meter in the car, it seems the mpg is only significantly higher for the first few minutes of driving, and yet it takes nearly 30 minutes to get the engine up to full temperature in the winter. After 5 minutes the engine temperature is probably less than 50 degrees. My guess is that a simple, cheap, silent and reliable oil sump contact heater, of the self-adhesive type, and of perhaps 125 watts power, would be enough to warm the engine to a point where the fuel economy is reasonable from the time the engine is started. I would need to switch it on a few hours before drive-time, but at only 125w I could probably justify leaving it on all night along with the battery charger. I have a 100% grille block and a good engine undertray, so the engine would probably stay fairly warm even with a mild breeze blowing. I could also insulate the oil sump with PU spray-on foam, which would increase the effectiveness of the heater, and would also help to keep the oil warm for longer when the car is parked up away from home during the day.

So, I'm not sure what, if anything, I shall be doing about the pre-heater in the short-term, but I am looking forward to seeing what gains I get now with the alternator switched off.