motor started knocking, but not rod knock

Sketchy564

Sketchy564

Driver
a little less than a week ago, my motor started making a knocking noise out of nowear. Scared the shit out of me at first, but i know what rod knock sounds like and its definatley not rod knock. It sounds like its coming from the head or the front of the motor

one person told me its probably the timing chain rattling, or the timing chain tensioner
another friend thinks its the valves

its hard to tell what it is, but its definatley a knocking and not a tick. Anyone here have any idea what it might be? Or would be able to to check it out in person and give me your opinion?

i dont have a camera, so i cant post a video
 
sounds kind of like this, but not as "harsh" i guess you could say
.
 
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Lol. That's rod knock.
The only thing that can knock is rods.

Everything else like timing guides or valves make more of a tick. That video is knocking.

Here's what you do. Rev engine till you hear knock. Unplug each cylinder then plug back in. One by one. When the cylinder gets no spark and makes no knock. You found your culprit. Spun bearing. Bent rod. Etc
 
really doesnt sound like rod knock, ive had rod knock before and ive heard it on a friends car, this is something else

not to mention rod knock is a LOT louder. Maybe its a bent valve?

i drive my car hard, but i never rev it over 7.5k, the only thing that could have caused any problems is when my coolant temp sensor was bad, my motor was getting flooded out with gas

ive changed the oil a few times since then (like every thousand miles) but never the oil filter (dumb, yes i know, but that shits on there tight as fuck and never have an oil filter wrench when i have the chance to change my oil (cant do it at my place)

anybody else? any shops that know there shit i can take my car to?
 
Bring it.my way ill show you what cylinder and do a compression test to eliminate this bent valve theory...

Free cuz I'm in the same fucking position
 
your far as fuck though, idk if i can trust my car to get me there and back lol, but im down

and yeah, i gotta figure out if its my head or my block thats bad

cuz i have a perfectly good block just chillin, with a clean head attached to it, that i plan on using in my car
 
forgot to mention that the head was making all sorts of wierd noises when it was originally in my car lol (the head on the other motor thats just chillin)

its either the valve shims being wrong, the exhaust cam being off time, or maybe something else. Im either gonna buy a good head and swap it to that block, or just take the head off and take it to a shop thats really good and have them do their thing
 
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that video is a spun rod bearing known as rod knock in some cases

---------- Post added at 11:55 PM ---------- Previous post was at 11:55 PM ----------

take the oil pan off and wiggle the caps
 
too much gas mixed with oill = no lubrication wich would cause a spun bearing, and it doesnt have to be loud
to be knocking.
 
secrets2k said:
Just give up on 240sx u have the worst luck with them lol
Click to expand...
wanna buy me an is300 or an STI?


i really dont think its rod knock, as i said ive heard and had it before and this doesnt sound like it

also, ive been driving on it for a week now, and i drive kind of a lot, and it hasnt gotten any worse. Rod knock usually keeps getting worse and worse till you blow a hole through your block

anybody here know there shit that can check it out?
 
wouldnt a spun rod bearing make it run like shit also?

my motor doesnt run awesome, but it doesnt run like complete ass either. It still pulls alright, but i know theres some power missing that isnt there

also its been smoking a lot more latley after idling for more than a 45 seconds to a minute, wouldnt valve problems cause your motor to smoke a bunch from the oil?
 
It's a spun bearing. I have that same shit now.
And Chris Jackson knows his shit. You may have had a bent rod causing rod knock before but that video is a spun bearing.
Do what I said about each spark.

Your gonna drive it till the bearing seizes to the crank. Breaks a rod. And puts a whole through your motor.

All because your not taking advice that your asking for.

Compression test
Coil pack test.
You have your answer.
 
not all rod knocks sound the same i heard a miata one time that sounded exactly like timing chain rattle but it had a spun bearing
 
crayZwhiteboy said:
It's a spun bearing. I have that same shit now.
And Chris Jackson knows his shit. You may have had a bent rod causing rod knock before but that video is a spun bearing.
Do what I said about each spark.

Your gonna drive it till the bearing seizes to the crank. Breaks a rod. And puts a whole through your motor.

All because your not taking advice that your asking for.

Compression test
Coil pack test.
You have your answer.
Click to expand...

what will a compression test and testing my coil pack do? I know my compression is low on cylinder three, but thats not gonna tell me why its knocking
 
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