My civic is knocking from timing side, wondering what it is before I start buying parts, it's an mpfi converted d15b2 if that matters.
Tried to figure out if it was the tensioner or water pump, then took them both out and they looked fine. The harmonic balancer is missing a chunk
maybe that caused the crank to get thrown of balance, the oil light never came on, no CEL, always check oil levels and the engine was never abused
but overheated once about 2yrs ago. Anything helps, thanks.

 

When does the noise happen?
is it constant, or happen at certain speeds?
Is there visually anything obstructing anything near the belts?
How many miles?
Are all your timing covers installed?

 

noise happens after car is warmed up
it stays constant at 800-1200 rpm then disappears anything above that
nothing obstructs the belts
block has 255k but had a "rebuild" dont know what the previous owner meant and the head has less than 70k and fully rebuilt
the top timing cover is removed

 

here is my vid: sorry its 2 seconds long i accidently touched the screen with out realizing causing it to stop
hopefully this helps out a little

 

Are the valves all in adjustment....Man just from the 2 seconds that sounded bad. if it were me and everything externally checks out(belts,timing,valve lash, alternator,ps,ac,plugs) I would pull the head and oil pan and inspect the internals

 

I took of the drain plug and saw no metal on it, then drained oil and inspected it with a magnet and it was still clean, I'm gonna take of the pan off as soon as I get the exhaust out of way, I'll update with pictures when I'm done, thanks.

 

i pulled the engine and the 1st piston has play in the rod bearing, the play is side to side

 

yeah it can have side to side play some because there is no spacers taking up the gap, you don't want any up and down play in the rod. That would cause a knocking noise.

 

imma just rebuild it, maybe it was piston slap, the cyl walls look to have some wear

 

I'm leaning the problem being to being bent valves, because the tick or knock goes away at higher rpms

 

Anything internally that is bent or damaged would not go away with higher rpms, if anything it would magnify the noise.

 

can it be spark knock?, like detonation, I forgot to mention that I have old shitty 87 octane in the tank

 

here's a pic

 

looks to be your issue, seems to me the one on the far right is the only one that wore correctly. The others look to be bad and irregular wear.

 

well unless your +11:1 cr then 87 would be OK.

 

The crank seems to be in good shape, aswell as the pistions,rings, and rod journals. Imma blame the crank pulley on being the problem due to it missing a huge chunk causing the bearing closest to the timing belt wear out faster than the others(causing it knock closest to the timing belt)