The term "mains" refers to the bearings that surround the main crankshaft journals and the journals that form the axis upon which the crankshaft spins. You have main bearings and main journals. A knock from there is an unmistakable, awful, sickening sound that causes a mechanic to stop, remove his cap and place it over his heart for a moment before he says anything to the friends of the nearly deceased..... sort of the death rattle of car engines.

Frank

Thank you, Frank!

You are exquisitely describing the look of horror on the faces of the two very-kind mechanics (I call them Saints) who (separately) had me immediately turn off the engine after listening for just a few seconds to the knock. The look on their faces after I got out was similar to a doctor trying to find the nerve to tell a husband that his newly wed bride had only a few hours left to live. They were speechless for a long timeá.á.á.áand stunned that I even made it the four blocks out of town, much less back into the wilderness.

Your early advice made me realize a rebuilt engine was necessary. Thank you!

Blessings,

Richard