My stock 61x engine threw a rod. Why did this happen?

[E350]

I am not arguing, I am just stupid. If it was to Measurement Two is to, in effect, measure the big end at the crank, wouldn't just a thickness (feeler) gauge be more accurate as in Measurement Three?

I am not getting how/why a dial gauge works at the small end unless it is to measure the looseness of the big end on the crank by seeing how far the small end moves side to side. Confusing to me . . .

 

[Harbor]

They want to know how far the small end is moving around... the small end is picking up all the various stacked up wear clearances in the big end, that movement from those clearances added together is then multiplied @ the small end due the rods length...

The small end is connected to the piston, the piston is reciprocating very fast (piston speed) and it’s movement needs to be kept in control or it can hang a ring on a port or bust a skirt or ?

Measuring #3 with a gauge can’t tell you #2 movement...

Have a look at the specs on those and you’ll see the stack up allowance

Hope this helps

Iam out