PeachParts Mercedes-Benz Forum - View Single Post

Biotour · #9 05-19-2009, 11:45 PM

well the knocking came back again, and i believe the valve adjustment was just a coincidence. i drove another 600 miles or so and when i was pulling off the freeway after a day long drive last night i heard the knocking at idle. i pulled over and checked the oil level and sure enough, the dipstick was completely dry. last week when i first noticed this knocking noise, the oil was at the low mark (it had been leaking because i didnt have the valve cover bolted tight enough the first time around) and i just topped it off and didnt really think it was caused by low oil. i was convinced it was caused by the valve adjustment because that was the most recent thing i did to the engine.. but the oil is what must have caused it in the first place.

today after adding oil (about 4 quarts topped it off) and searching everywhere for leaks, and letting the engine idle for 15 min or so in hopes the knock would fix itself (as it did last time) to no avail, i decided to do an oil change. turns out the oil fill bolt was so loose i was able to unscrew it by hand. not sure how this could have been, as i clearly remember tightening it pretty good last time i changed the oil. the black paper gasket on the bolt was split and looked pretty bad. i replaced the gasket with a copper one and gave it fresh oil and a new filter. hopefully the bolt was the only place that oil was leaking.. it seems like there are a few oily spots around where the ip bolts to the block, and on the other side of the engine behind/below the turbo, are these common places for oil to leak?

so now that its got new oil i tried letting it idle for another 20 minutes, it heats up but is still knocking. what do i do? i really dont want to drive it while its making this terrible noise. im afraid of rolling a bearing or doing something much worse. and i am certain that this noise is not caused by the air cleaner, as the knock is much louder when im laying under the car than when i am standing over the engine.