I want to drop my engine out for autumn/winter maintenance. I'll obviously need to drain the coolant, do I need to drain the oil as well? Can I get the coolant back in to the system once it's out to avoid any moisture freezing in the engine?

And what rotary tools do you all recommend, eg which specific Dremel is good for bike jobs?

Cheers,
David

I don't see why you'd need to put coolant back in. If any moisture does get into the engine, I can't see how you'd end up with enough to cause any damage from freezing. Just make sure it's all out so it doesn't go everywhere when you move the engine. There are drain plugs on the front cylinders as well as the one on the water pump if you want to be really sure. I guess taking the oil out depends on exactly what work you are going to do, and if it needs changing or not. Sod's law says if you don't drop it, something will crop up meaning you do. For the sake of a few rounds of beer, I'd drop it out and replace it when you've finished tinkering, unless where you are storing the engine is really cold and damp, in which case you might find the oil will help stop any corrosion forming inside the engine, but I'm not sure if that's likely to happen or not ....