W164, OM642, afraid to hydrolock the engine
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Joined: Jun 2016
Posts: 30
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2009 ML 320 CDI
W164, OM642, afraid to hydrolock the engine
Hi, I am replacing the oil cooler seals on a 2009 ML320 diesel and I forgot to drain the coolant before removing the air intakes.
The result was some coolant migrating to the air intake holes.
I can remove some of the coolant from the intake holes but I am afraid I will not manage to remove 100%.
Is there a risk of hydrolocking the engine if some coolant gets inside the cylinders?
Attached some pictures.
Thank you for helping me.
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Joined: May 2017
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From: West (by God) Virginia
83 300D 617T(retired), 96 E300 606n/a(retired), 99 E300 606T(retired), 07 E320 BT, 14 E3504M
Remove the glow plugs and unplug the CDI control unit then jump the starter relay until you are satisfied that the cylinders are free from coolant.
Nothing is likely to happen as is, depending on how much you dropped down there, but to be on the safe side, that's what I would do. Last time I quoted a reman 642 engine from MBZ it was around $17k. (Used ones are cheaper of course)
Better to be safe than broke!!
Also, side note, burnt and/or unburnt coolant and DPF's don't play together well, so keep that in mind.
Nothing is likely to happen as is, depending on how much you dropped down there, but to be on the safe side, that's what I would do. Last time I quoted a reman 642 engine from MBZ it was around $17k. (Used ones are cheaper of course)
Better to be safe than broke!!
Also, side note, burnt and/or unburnt coolant and DPF's don't play together well, so keep that in mind.
Thread Starter
Junior Member
Joined: Jun 2016
Posts: 30
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2009 ML 320 CDI
Thank you PGSurface, where is the CDI control unit? Is it the glow plug module or the Engine control module?
Or should I just start the car with the diesel injectors electrical cable unplugged?
Or should I just start the car with the diesel injectors electrical cable unplugged?
Thread Starter
Junior Member
Joined: Jun 2016
Posts: 30
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2009 ML 320 CDI
I was wondering to start the car without the glow plugs and with the diesel injectors electrical cables unplugged.
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