Originally Posted by Syncrosimon
The reason for this thread, well something has changed in the engine. The sound is different, there is more top end clatter. The motor pulls strong and revs freely. I am concerned that something has begun to happen, and want to catch it before it gets expensive.
Have you checked the valve clearances lately? Often the first thing to wear out in these motors, at anything from your mileage up, will the inlet cam follower roller bearing - you'll be able to check that out when you pop the top to take out the water pump.