Loud Knocking

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J

jeppreyboy

Junior Member
I was driving my car in a normal way and all of a sudden i can hear this loud ass knocking noise in the engine. I pop the hood and it sounds like the pistons are knocking around the inside of the engine. I have a JDM B16 that I bought from Hmotorsonline.com just two weeks ago. This engine can't be messed up already, I haven't even gotten a chance to get on it. Someone tell me what this can be. Thanks.
 
Is the sound coming from inside the engine? If so, does it sound like someone is knocking the inside of the engine with a hammer? (Metallic rapping)

Best case is the sound is not really from inside the engine, but something in the engine bay has come loose and the knocking around.

Worst case is you have spun a rod bearing.
 
Take off your oil filter and open it up - see if you have metal shavings in the filter...if you do, a bearing has most likely let go. It is time to drain the oil then - metal in it? If so, bad news...drop the oil pan and start looking for the bad bearing - it is rebuild time!

Kirk
 
Originally posted by gtpilot@May 2 2003, 11:58 AM
If so, bad news...drop the oil pan and start looking for the bad bearing - it is rebuild time!

Kirk
Click to expand...

if it is the bearing..which it probably is..(from what other people have told me)..how much rebuilding will i need to do??
 
That depends on how much the motor has been run since you heard it FIRST knock...you could need a complete rebuild - I have seen scored cranks, blued rods and damaged pistons because the bearing was completely gone...I have seen a piston that has collided with the head also, so a new head was in order also. You just won't know until it is opened up...

You could also be lucky enough that all you will need is new bearings...but I doubt it.

Follow what I previously described and do a little investigation and then tell us what you find.

Kirk
 
I spun a bearing in my H22a and it turned out to be cheaper to swap in a JDM H22, it cost $2800 to replace the engine and tranny. (Didn't need a tranny just figured I'd do it while it was apart)
 
what does it mean when you "spin a bearing"? where is the bearing located, how does it happen, and why is it so bad? sorry for the n00b question i jus never know what it means.
 
Originally posted by GSRCRXsi@May 2 2003, 04:24 PM
what does it mean when you "spin a bearing"? where is the bearing located, how does it happen, and why is it so bad? sorry for the n00b question i jus never know what it means.
Click to expand...

How Stuff Works - engines - take aread of this, you will get the general idea of how all the pieces go together.

Kirk
 
kirk, i was just wondering how the bearings on my car to break. what could be the cause? I only had the engine for two weeks and only maxed the car out like 3 or 4 times, just to test it.
 
OK...I havent been able to see if it is my rod bearings that are causing the problem but I have another question. A friend of mine told me that it most likely is the rod bearings. He told asked me that if i rev my car up, does the sound get louder? I revved my car up and the knocking sound is gone. When i idle it comes back. Can it still be the rod bearings or is it something else?
 
Seems to me that if it was in the motor it wouldn't go away when you rev it.You need to get in there and see where the noise is coming from.
 
You really should check your oil and filter before you drive it much more. That will be the easiest way to check.
 
sounds like a rod knock to me. you probally have a worn out rod journell or bad bearing. its probally not that bad yet though. it will get there so a rebuild of the bottom end is in order. when you rev it, it will create more oil pressure and will quiet the knock some. so you may think its gone. but trust me its nothing a mechanic in a bottle will fix. just rebuild it DUDE.... B)
 
does the sound go away when you press in the clutch?
I have seen a sohc civic that sounded like it had a rod knock, but it turned out that the throwout bearing was the cause of it.
 
Have you ruled out valve tap yet? I had an adjustable cam gear let go on me and it caused a loud tapping/knocking noise. Does the motor have adj. cam gears? If not, maybe the valves need adjusting. Just a thought. Good luck.
 
Ok...for those of you who have been giving your .02, I finally was able to drain my oil today. I guess the good news was that I didnt find ANY METAL shavings or parts in the oil. The bad news is that the oil that i drained smelt like PURE GASOLINE!! Anyone know why? Also, could this oil and gas mixture been the cause of the engine malfunctioning and knocking?
 
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