I have a 97 E420 that has 78KM and so far has been a great car but has a loud tapping coming from the right side of the engine when it is warm. Now I've replaced the lifters and it still does it my dealer mechanic said that it may be an effect of the 50,000km oil change, That there could be a piece of desintegrated filter lodged in one of the jounals. I don't want to have to take the heads off but the noise is driving. The sound is audible from a far say 20 feet and goes away when reved, but returns instantaniously with return to idle.
cheers

Thomas

 

You need to pull the valve covers and check the plastic oil tubes running between the cams, they have plugs in the ends of them that tend to pop out, preventing the lifters from getting oil. I've seen this quite a few times, its not a major repair. The tubes are easy to replace.

 

Hi Thomas

I have 97 E420 with same problem, the tapping goes away when i get oil change, I was wondering if you try replacing plastic tubes and if it fixed the problem.

Thanks.

Azad

 

I am having the same problem as per your descriptions. I changed oil and the tapping noise disappear for about 2000km. Then, it came back. I added the valve/lifter lubricant to reduce the noise while idling.

Can anyone send me the procedures in removing the valve covers and replace the tubes/Caps?

Should I replace the Caps and Tubes?
Are they expensive?