Is this normal pump whine? (m112/113)
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E350 4matic
Is this normal pump whine? (m112/113)
Engine has approx 74K mi, oil changed two days ago, after liquimoly engine flush- used 1.5 Bottle and idle 12 min, drained 10 minutes and poured 5W40 Mobil1.
Since M112/113 are known to whine, I am unsure this is normal.
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In my memory, I never heard this sound before.
first video is without belt.
second video is with belt on.
Any ideas?
Since M112/113 are known to whine, I am unsure this is normal.
In my memory, I never heard this sound before.
first video is without belt.
second video is with belt on.
Any ideas?
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C320
No that's not normal. Did it make that noise before the flush?
I usually let oil drain over night. You'll be amazed how much more oil drains out. Whatever they put in that flush is still in your crankcase.
I usually let oil drain over night. You'll be amazed how much more oil drains out. Whatever they put in that flush is still in your crankcase.
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E350 4matic
Amd yes, it sounds like this after flush. Right after flush, it sounded normally, but after 1 day it sounds like this. I am changing oil and filter one more time tomorrow.
Does M113 have pressure sensor? I don’t think this engine has low pressure, but curious.
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I can't tell if the noise is from the oil pump or some other part of the engine.
Last edited by tjts1; Mar 14, 2023 at 04:27 PM.
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E350 4matic
No, the M112/M113 doesn't have any kind of oil pressure sensor, not even oil pressure switch for an idiot light. The only thing you have to go buy is the oil level sensor. The o-ring between the oil pick up tube and block is a known failure point but usually this happens on high mileage engines.
I can't tell if the noise is from the oil pump or some other part of the engine.
https://youtu.be/XApz7pzbG6M
I can't tell if the noise is from the oil pump or some other part of the engine.
https://youtu.be/XApz7pzbG6M
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E350 4matic
I was thinking all the goos clogging oil pickup tube, but since it is low mile engine and I did 3000mi oil change 2 time before, maybe not that. i really have no idea so I was thinking trans pump too. Thanks for the help tho, I wanted to save the engine.. it made startup tapping noise and after flush, it is gone now.
