Hallo,

I own a 420 SE (1989) with 310000 kms. Since quite some time now I can hear a ticking noise coming from the engine when I accelerate: it becomes louder when accelerating and it’s hardly audible as soon as I stop accelerating.
With the engine idling, I hear a ticking noise at both sides coming from beneath the black covers.
Uptill now I had the following parts replaced:
-2 camshafts
-16 lifters
-16 rockers (cam levers)
-timing chain
-distributor cap
-spark plug wires and boot
-gaskets inlet manifolds

What else should be replaced/repaired to get rid of this ticking noise??
Or is it just simply a question of a bad ignition timing that sets off the valves??

Please let me know something if you recognize this problem…..

Thanks in advance,
Rémy K.

Well I'm not to familure with that engine but I do know that even new lifters need good oil psi. So you might want to see if it has a acsess point to check the oil pressure going to the top end.

You mean your car is 420sel, I hope some one has checked the oil tubes when they were working on the cam shaft and lifters. There are oiler tubes, one on each side, which eithe brake or block and do not provide the oil lubrication to the cam shaft. This is very typical on these cars, very inexpensive (oiler kit US $4.68 from this site) and very easy to do. Juso pop up the valve cover and take the tubes out (carefully they are usually very britle).
Let us know, if this job is done or not.
If it is done, then I can explore some other possibilities, but If this was not done, this might be your problem.

Good luck.

__________________
87 420 SEL
Looking for a nice mid 80's MB diesel.
87 BMW 528e (Sold)
99 TOYOTA 4Runner
1989 Honda Accord (Sold)
1988 Honda Accord (Total)

Hi Benzmatic,

thanks for your advice: I'll look into that before anything else is done...!
And it is a 420 SE, from Germany: I live in Holland.

greetings,
Rémy K.
420 SE (1989)
310000 kms

you sure you don't have an exhaust tick? running gear noise will get quicker
but not louder.

george

Hallo Benzmatic again,

according to the bill, I paid for the replacement of the oil tubes in may 2002.....
Do you think it's possible that they could need replacement again after 2,5 years??

Thanks,
Rémy

Whenever the rockers or cam are done/replaced, the clearance between the rocker tip and valve stem can change, so part of the job is to use the special MB tool to measure the allowable thickness of the shims (the 'thrust washers' Cigar mentions below) which fit between the rocker tip and the valve stem. This is a very time consuming process. Are you sure it was done? The noise you describe could also be a lifter, plugged with a bit of dirt in the oil, easily checked and repaired. Try running some good top-end cleaner in the oil, change the oil and filter, to see if that doesn't clear it up. Do a search too, as there are many posts and decriptions of this problem on this forum.

__________________
1986 560SL
2002 Toyota Camry
1993 Lexus

How often have you changed the oil and filter? When idling, how many bars of oil pressure? in gear and in neutral?

Could be worn "thrust washers", commonly called valve shims or pucks.

__________________
1989 420 SEL