90 300SEL tick-tick (subject again) - PeachParts Mercedes-Benz Forum

90mbenz · #1 08-19-2002, 04:26 PM

I've read most of the posts regarding lifter ticking, but didn't find one specific to the 90 300 SEL. Engine has 185k miles and has been properly serviced (including appropriate timing chain service at correct intervals). Noticed some startup ticking months ago, and made sure to use the proper Bosch oil filter (with internal check valve) at oil change time.

Well, lately, noticeable ticking while driving normally....but sometimes goes away. Always tick on startup, but often will die out after pressure builds to normal. Haven't isolated it yet, but I think it's only one valve/lifter.

One of the posts described how to change out a lifter, but wasn't for the six cylinder 300 type engine.

Nice site - wish I'd found it when I got the car a couple of years ago. It's a real road warrier.

Any advice?

Benzmac · #2 08-19-2002, 09:02 PM

I have seen the camshafts wear and cause this noise on the 103 engine.

If this happens, just replace the cam and all of the lifters.

fasthair · #3 08-20-2002, 12:57 PM

If this happens, just replace the cam and all of the lifters. [/B][/QUOTE]

I know you meant rocker arms not the lifters. The lifters have to be swaped over to the new rocker arms. But I do agree it sounds like the camsaft is bad. It has enuogh miles on it to have earned a new one. Pull the valve cover and look for a "flat lobe" which really won't be flat but have wear on it that will be easy to see when compared to a good lobe.

fasthair

90mbenz · #4 08-20-2002, 03:59 PM

Thanks much fasthair and Benzmac......helps to get confirmation about a problem.

engatwork · #5 11-13-2006, 08:57 PM

I've got a '89 300SE in the shop with the exh cam on the #4 cylinder flat where it is supposed to be rounded. The rocker is worn in an unusual way too. The car had the ticking noise all the time - hot or cold.

86560SEL · #6 11-15-2006, 12:29 AM

My 85' 380SE w/268 has a tick too, but its nothing more than I have heard on newer lower mile cars. It also seems to have more of a knock between 1500-1800 rpms that can be slightly heard when the windows are up and radio off. I think it is due to a worn camshaft. I wonder if something like Amsoil synthetic would help prolong the life of the engine? Or- at least quieten it down to a minimal. I have heard that it does quieten engines on other cars- do not see why it would not work on Mercedes.