jrios

I am trying to identify a loud knocking noise when the RPMs are brought above 2500 RPMs. The noise sounds like a rod knock but anything below 2500 RPMs the engine is quiet. Just to give you a little history on the motor I ran an out of balance clutch on the motor and cause excessive wear on the main bearings causing low oil pressure. Since then, I had the crank turned and replaced the main and rod bearings. I have ran the motor for about 1000 miles with no issue after that. Then I started to get valve train knock. Upon further inspection I found the lifters had gone bad. I replaced the lifters and and started the motor and everything seemed fine except for when I bring the RPMs above 2500. I double check the valve adjustment and everything is correct. Anyone have any ideas on what the noise is?

Thanks

TooLateVTEC

iTrader: (2)

Any way to post a video?

So its dead quiet until 2500+ then it starts knocking?

When the crank was turned, did the correct sized bearings get installed for the stock size journal PLUS the amount taken off the crank?

93306

i had this happen once it would only knock around 2500-3000 it ended up being a wrist pin had came loose

jrios

I check the bearing clearances when I put it back together and everything was within spec.

I was thinking it maybe a wrist pin too. When I try listening to see where the noise is the loudest it comes from the bottom of the motor and the throttlebody. I did a compression check also and it was 175 to 183.