Ok first off im new to this forum. I've had a loud knock after starting my jeep when cold. Btw its a 2000 wrangler 4.0 with 122000 milea. I Recently I replaced my timing chain at a friends house, took about 6 houra to do. But before that it sounded like piston slap maybe. Here is the weird thing. After I put the new chain on and put everyrhing back together I started it and the sounds was gone completely. So after that I started to drive it the next couple days with no knock or slapping what so ever. After the 3 day the noise came back just as loud as it was before. I used mobile 1 before and so im using penns oil. What do yall think would cause it to come back? Timing off a little? Any input with be appreciated! Thanks
Last edited by lsuguy4; 11-05-2013 at 08:49 PM..
Reason: changing the title
No my filter is not fram brand. The noise is there right whwn I start it up cold but goes away after warm. If I turn it off it comea for about 30 seconda and then goes away. Why wouod the noise stop after timing chain change? And came back a few days later?
Post a video so we can hear the noise. If it goes away after 30 seconds it ain't a bearing. My guess would be a lazy lifter. It is also possibly end thrust on the cam shaft. With cold oil the oil pump requires more force to turn it and since the drive gear is helical it forces the cam shaft to move to the front of the engine. Did you notice the timing gear cover when you had it off? Was there any signs of the sprocket hitting the cover? The camshaft has a thrust plate behind the sprocket to prevent the camshaft from "walking" to the front of engine...it could be worn. Also the rear camshaft journal is a blind hole which can allow oil pressure to get trapped and push the cam forward. There is a relief hole in the rear journal to bleed off this pressure which can become clogged.