How Do I Spot a Bad Lifter?
 

I've got a tappety-tapping 190e its noisy until the oils fully hot. Then okay but its getting worse, it sounds like just one lifter is the culprit but how do I tell which one? Will there be obvious damage to see? Can be tappet be adjusted or it is self adjusting with replacement the only "repair"?

Mike.

You might want to try using diesel rated oil for a change or two. I believe it was Larry Bible made this suggestion. I did it for the old 87 190e I had and it did improve a noisey lifter.

The diesel rated oil has better detergents and thus cleans the inside of engines better.

Haasman

Or try the BG product MOA.

I always listen to the valve cover and the intake or exhaust runners with a stethescope. Usually it gets exactly the right one, sometimes it only gets me near. Once under the valve cover the lifters are in the rocker arms. There should be no play (clearance) when pumped up. A bad lifter can be collapsed with a little force from one's hand (pushing the rocker against the lifter. If it collapses the rocker will then have clearance.

Thanks, I've heard it said that ATF is useful for noisy valve gear too.

Anyone with more input? :)

Mike.

190E tapping
 

2.6 engine?

I have had the same issue, but it came from poor workmanship from my machine shop. On the second head, the head was not vatted, and there were oil deposits left in the bolt holes for the rocker arm towers. When the oil reached a high temp, bolts started backing out, causing a slight tapping, which I thought I had a lifter going out on me. I kept driving, changed oil (didn't use any additives) and the slight tapping stayed, and got worse...so I removed the valve cover to find a rocker arm tower bolt that had worked it's way out of the threads. If you have this issue, make sure that the threads are not on the bolt, because you may have to use a helicoil to repair it...

If you need an additive such as transmission fluid, you need to replace a lifter, or the cam if you have pits and/or wear on the cam lobe where the noise is coming from. Check, check and double check....take your time, take a look at the cam at night with a strong light (while rotating engine) to make sure you have no camshaft wear. If you need a lifter, locate which one it is (like Steve said) and let me know, I have a box full....