jimtanner

My cam locked up on the passenger side and broke the timing belt.I had the head reworked by a shop that only does heads. I installed a new timing belt and water pump, put tension on the double gear on the cam and secured it until the cam was locked in place.put all timing marks in place and assembled everything. It runs good but has this tapping noise. The noise is steady when it idles. If you push the gas a little the noise goes away. When driving you don't hear it until you let off the gas.Do the lifters have to be primed? I ask that because I had a subaru that made that same noise until I took the lifters out , flushed them out and primed them with oil,then the noise was gone on that car. " the noise was not there before the cam locked up. PLEASE HELP! JIM

jimtanner

Need Help.Have someone that wants to buy my truck but they are afraid of the noise. HELP!!!!!!!!!!!!!!!!!!!!!!!!

MTL_4runner

The lifters on the 3.4L are solid metal shims so it is likely that you have lifters that are out of adjustment causing the tapping sound you hear at idle. If you want to fix it you'll need to pull the valve cover again and use a feeler guage and a special tool to remove and install the correct size (thickness) shims. The procedure has been outlined in a few threads already so I won't go though it in any detail here. It could also be that the cams are not "loaded" properly since the intake and exhaust cams are spring loaded against each other to remove all gear lash and you may be hearing that as well. There was a service bolt you needed to install before removal so if that wasn't done, that may be the issue as well.


How did the cam manage to lock up? What was done to the head to bring it back from the dead?