Loud engine ticking

[pablo2696]

Hello all

In the past few days my car's engine has developed a loud engine ticking that is turning to be pretty annoying... My car is a 93 500E with over 200k kilometers. I checked through the oil cap and it still has the plastic oil tubes.

Around 300 kilometers ago I replaced oil level sensor, oil pressure sensor, lower oil pan, oil housing check valve, and other minor things. I also replaced all vacuum hoses, lines and elbows. The car runs better than before and now the oil pressure gauge is working! The average pressure when the engine is at running temperature and while iddling is 1bar. When accelerating past 2,000 PRM it is 3bar.

I also replaced the oil and changed oil grade as per my mechanic recommendations. I used Total 15w40 semi-synthethic and now I am using Liqui Moly 10w40. So immediatly after the oil change my engine was as quiet and smooth as it had been lately. Then like 1 week ago I started hearing a small ticking noise and yesterday, after flooring it multiple times on the highway to check the kickdown, the noise started getting louder and louder.

Attached please find the video of the noise. You can always hear it no matter how hot or cold the engine is. Do you think it might be blown plastic oil tubes?

Thank you!

 

[gsxr]

That does sound a lot like 1 or 2 plastic oil tubes with the ends popped off. If the ticking is noticeably louder on one side, pull that valve cover for inspection. It will be very obvious if any tubes have the ends popped. If so, replace all 16 on both cylinder heads with aluminum tubes, and you'll never have to worry about this again.

 

[MBchap]

My 94 E500 has this same type of clicking, perhaps a little quieter. Just started mid-November, both when engine is cold and normal operating temp. Has about 180k miles and I replaced the plastic oilers with the aluminum last year. Been running great up till this recent issue... I'm not running the car now and it's causing some distress. Is it possible that one or more of the oilers has worked free or is this more likely a lifter or rocker arm? I could not determine where (which side) the sound is coming from... Thank you for any input.

 

[Kridre]

I suggest you to remove both valve covers and trying to push lifters one by one with a finger. If any of them is going down, that meant that it needs to be replaced or cleaned. Of course, the cam lobe of the lifer you are testing must point upwards. I had the same issue and found two lifters collapsed in the left bank. After cleaning they are hard as a rock, don't know if issue is fixed because my car is in pieces.