Stop start issues

[London West AR]

I live perilously close to London's Ultra Low Emission Zone and within the Low Emission Zone

This is London specific but a lot of cities and towns are moving to congestion zone charging based on emissions

But also there is a mandatory requirement to turn off your engine after a minute of idling

It took me two hours to drive from Twickenham to Wembley the other night on the way to our monthly meet at the Ace- there was no way my Banner battery was going to cope with that kind of stop start cycle

Instead i came to a rolling boil just as i finally arrived at the Hanger Lane Gyratory system

So two questions

How do i check that my electric fan is working?

I have a feeling it was just the heater with the fan turned on  that kept me from doing serious mischief to the engine

But also is there any plausible way to do stop start in a Caterham?

Would a Lithium battery be better or worse?

Auto stop start cars generally have bigger batteries but that  introduces a weight issue where Lithium helps but the existing offers seem to be the same capacity for less weight rather than more capacity for the same weight

And will the starter motor cope?  

PS I have a 1600 VX 8 valve so no cat but at least it produces less heat than most other engines

[Jonathan Kay]

Private Message sent.

[SM25T]

Is your cooling fan controlled by a thermo switch in the top of the radiator ? If so, with ignition on, pull the cables off the switch and short them together. Expect a spark. Fan should run. If not, check you have 12V there, if not, then fuses. If it runs ok, remove fan switch and check its operation in a pan of water that you warm up to boiling. It should be marked with its opening and closing temperatures ... example 92C and 87C. Use a multimeter to see when contacts close.

[SM25T]

As for stop/start .... it's a whole new world of complication with a huge battery, don't even think about it.

[ECR]

You can also wire in a manual fan override switch enabling you to switch it on if you're feeling nervous

[Wrightpayne]

I've read of issues where, due to the coolant being low in the top of the rad / air locked the fan switch is inoperative as not submerged.

[London West AR]

Thanks all - yes i definitely have  had an air lock problem so that's a possibility

I like the idea of a switch