After AViVA's starter motor let me down a few times, I thought it was time to fit a new one.

The old one suffered from a sticking solenoid and needed some gentle pursuation with a hammer.

The speed on the Thames is restricted to 8 kilometres per hour, which is about 4.2 knots. But how do you know what speed you are doing?

Removed the starter motor with difficulty. Having a look in the workshop to see if anything wrong. Connected to battery and works fine.... so I wonder what is preventing working in the boat. Seems to be a Kubota 1kw. 

Next job to check the wiring. Seems to be a wiring fault, because it all works on the bench and now back in the boat. Went for a trial run and starting no problem.

One of the electrical contacts on the old temperature sender had broken off. This meant no connection to the alarm and light on the panel. A new one was ordered from Beta Marine.

Cooling water was partially drained (and saved) and the old sender came out with no problem. The new one is certainly a different size but fortunately the staff at Beta Marine send an adaptor and this made the fitting straightforward.