We were taught early on in our sailing career that it was best if we had a clean engine and engine room since any problems would be obvious. We were lucky with our first boat, the Dufour, since it had 2.5 engine hours when we bought her and was spotless. It was easy to keep this clean.
When we bought the Moody, the engine had a shade over 3,000 hours on it. The engine room floor was also not clean. This of course means that it is difficult to see if we have fresh engine problems. So we decided that we need to make sure we have confidence in our engine before we go on our great adventure. Step one is a clean up of the engine room before we review the engine itself.
Now with a clean engine room floor at least we can see what is going on. Our job is to spot any problems and keep it clean.