Posted 11/23/2012 20:21 (#2713085 - in reply to #2712946) Subject: Re: JD Tech-engine trouble JD 4850
Never seen it since but once on a 4040 we worked on the brass insert on the ether inject came off inside the manifold (or was it broke the nozzle off....too much time has passed) and buried itself in the top of a piston and cracked it.
Like others have said, not listening to it there is a large number of things it could be. Never tried Bern's approach - but I like it, could be a place to start.