Hey folks, New to the forum with my Old & Grey P38. Got an issue that I'm hoping you can help me solve. Recently, my P38 was in rapid fire mode, meaning, I would start from a stop to start rolling and a disturbing rapid fire, knocking was sounding from up under the front end. This only becomes apparent when I'm accelerating from a stop and while accelerating. Thought it was a damaged fan shroud making contact with my fan, but that proved incorrect when the shroud was replaced and the accelerated rapid knocking persisted...Any thoughts?

 

My guess is Diff

 

^ diff sounds about right

 

...or blown head gasket

 

My HG had an exhaust leak sound popping (like a lawn mower) that came on suddenly. You can see where it burned a path to the outside. Locate by using a length of rubber hose, listening thru it as you move other end along the gasket edge.

For the differential, drain the front diff, with that kind of noise you may find a silvery liquid and chunks of metal. If not, refill with 85W150 lube.

And I guess in some cases it could be a cracked spark plug. However, Murphy's Law for Land Rovers is against you (anything that can go wrong on a Rover usually does, in descending order of repair hours and parts cost).