with a ruler or anything that you can measure with
I THINK you use a plumb-bob
A precision straight edge, dial indicator gauge, and a V-block setup would be used to check the straightness of a crankshaft. The crankshaft is placed on the V-blocks, the straight edge is positioned along its length, and the dial indicator is used to measure any deviation in straightness.
With Old fashion guages that measure the normal size of the run and then the rise of the lobe.
Glen fault
A precision straight edge and a feeler gauge would typically be used to check the straightness of a crankshaft. The straight edge is placed along the length of the crankshaft to visually detect any deviations, while the feeler gauge is used to measure any gaps between the straight edge and the crankshaft surface.
It is a measure, in thousandths, of how far the cam lobe lifts the valve open, off of the seat.
Straightness refers to how smoothly a surface or line deviates from being perfectly linear, while flatness refers to how smoothly a surface deviates from being perfectly planar or level. In other words, straightness assesses the deviation from linearity, while flatness assesses the deviation from planarity.
Depends on what you're checking. A piece of window glass works well for checking push rods for straightness. A machinists straight edge is good for checking heads and decks.
With a tape measure check the length of the camshaft by either checking the new camshaft or measuring along the top of the engine, now take that length and extend it out from the front of the engine to see if you have a straight shot out the front of the block to remove the camshaft, by default the fan, radiator and ac condenser will need to removed for the actual removal of the camshaft.
straightness, weight, cracksand journal wear
When you cross them over from one another