Help engine knocking

[Richrm125]

I have a 1989 325ix that's knocking very bad I believe the knock is coming from the head I've checked valves and for broken rockers I can't find out what this noise is.

[EatsHondas]

Pull the oil pan and check the rods for excessive play at the crank. Check the drained oil for fairy dust (chewed bearing material) also.

It's less labor intensive than pulling the head, rotating each piston to TDC, and pushing down on each one while watching/listening for a "thunk" as the rod settles against the crank.

[Richrm125]

Still can't figure it out. But I've been driving the car in every snow storm can't see it being a rod cause it would've granaded by now I would think

[tim88325is]

Does the sound go away when you push in the clutch? Trans input bearing can sound just like rod knock...

http://www.r3vlimited.com/board/showthread.php?t=204043

[spdracrm3]

Still can't figure it out. But I've been driving the car in every snow storm can't see it being a rod cause it would've granaded by now I would think

they can run a long time with a rod knock if its kept full of oil (guy in my neighborhood drives an old 70's ford truck with a bad rod knock ,been driving the bugger for two years that way)

a good test if you suspect rod bearing/knock issue is with it running pull plug wires (with insulated pliers or plugwire tool ) one at a time if knock lessens or changes/goes away on one particular cylinder you've found the issue .

[Richrm125]

Ok so I did the spark plug test didn't hear a change when they were pulled. I did another oil change no metal in oil. I'm leaning towards worn valve eccentrics

[spdracrm3]

did you adjust the valves?
usually noisy loose valves are described as a tapping or clatter (like a sewing machine) not a knock...certainly worth adjusting them to eliminate as a possible source ...

whats the state of the timing belt?