I have a jdm b18c bottom end with pr3 pistons and a pr3 head with a oem 3 layer head gasket. when i assembled the motor and put it in the car and started it you could tell the valves needed to be adjusted bad, so i did a valve adjustment for a b16 .006 on intake and .007 on exhaust. after i did the adjustment i started it up and it sounded nice and quiet but the next day it started sounding like there was something bouncing around in the head. i took the valve cover off and took the cams out and ran a magnet through it to make sure nothing was in it and couldnt find anything. now im guess the valves hit the pistons and are now bent. i would just like to get some other opinions on what it could be. any suggestions would be helpful, thanks

 

What type of gas are you using? what kind of ecu are you running? Ive heard an engine Ping before and it sounded like pebbles coming from the head.

 

Are you running adjustable cam gears did you check the belt tension ?

 

Most likely, the valves didn't hit the pistons. There should be plenty of clearance with those parts. Is the motor tuned? Did you make sure to tighten all of the valve nuts? Are any of them missing? B-series engines are going to make that sound, especially if you have upgraded the cams and valve train.

 

X2 on checking the valve adjustment nuts. Maybe also take a look at your lmas

 

The nuts are all tight because the next morning i went back and checked everything to make sure it was still in spec. i have been putting mid grade gas in it. i am useing stock b16 cams with stock cam gears as well. im running a chipped p28 with a b18c5 basemap and its not tuned. i did run the car pretty hard a few times the day before i adjusted the valves, could that of done it?

 

The sound is like something is hitting the underside of the valve cover, its hard to explain

 

Could be lma's at idle. How old is the head?

 

That's why I said take a look at your lmas

 

A couple days ago, I was going crazy thinking i bent a valve or something. I have a CTR piston setup with some pro2s and bending a valve is a huge possibility for me. Either way, I tried a valve adjustment checking the cams, looked all over the motor. Then i moved the valve cover a little bit to the right so that the cam gears didnt hit the valve cover and back to normal.. It was a wreck but thats what it was For me.

 

My advice take the head off and take it to your local machine shop and have them look at it and pressure check it and that will tell you really fast if your valves are bent cause they wont seat and that will affect alot of things did you check your valve lash?

 

Chances are you didn't adjust the lash correctly that there is more of less clearance there the there should be. More likely though the nuts also could've come loose. On all the valve trains I do I use blue locktite even if it isn't called for because the last thing I want is those buggers to come loose because even at factory torque spec they do more often then one would think they should.