Question about cranking engine

[juntjoo]

When I first did my timing belt and installed wrong, when I cranked the engine it made this sort of empty spinning sound -which never produced anything, not a single pop, and subsequently ruined my valves cranking it like that, and since then I replaced my head then did the belt right I'm sure (cross my fingers) because it made a stronger sound and popped a few times, but didn't start I think because I left some oil in the pistons for testing the piston rings, but that's another story.

So I'm just wondering what exactly is the difference in those two sounds. What's going on in the latter that makes more noise/vibration?

 

[Bouche Dag]

Compression when the belt is done properly and lack thereof when installed incorrectly.

When you bend your valves your pistons are just pumping air through the manifolds with no resistance. When the valves function properly there is resistance in the head causing the noise

 

[DSM1G90]

Did you follow ALL of the VFAQ belt installation instructions prior to hitting the key? If the instructions were followed, the motor should have taken right off.

Get the plug wires to the correct spark plugs - sounds like you got some wires crossed, if you got that popping sound.

 

[juntjoo]

Compression when the belt is done properly and lack thereof when installed incorrectly.

When you bend your valves your pistons are just pumping air through the manifolds with no resistance. When the valves function properly there is resistance in the head causing the noise

Oh duh, there it is. makes perfect sense. I feel a bit more elucidated now about this marvelous mechanical mystery before me. Thanks. I've definitely got me some compression now thank god.

 

[juntjoo]

Did you follow ALL of the VFAQ belt installation instructions prior to hitting the key? If the instructions were followed, the motor should have taken right off.

Get the plug wires to the correct spark plugs - sounds like you got some wires crossed, if you got that popping sound.

I'll double check, but remember I might have about an ounce or a bit less in each piston from testing the rings. How do you suppose that should effect things and should a few more cranks burn the oil out of there? I didn't put the exhaust mani back on yet so it was just spitting oil out the ports. Btw, I've installed plugs based on cylinders 1-4 from drivers side to passenger, and 1, 4, 2, 3 on coil pack.