Coolant pressure for a 2013 Mercedes Benz ML350 4 Matic?
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From: CT
2013 Mercedes benz ML350 4Matic
Coolant pressure for a 2013 Mercedes Benz ML350 4 Matic?
I have a 2013 Mercedes Benz ML350 4 Matic. I'm getting low coolant alerts on the dash on a regular basis. I top it off every time with the correct coolant but this time I decided to rent a coolant pressure testing kit to add pressure and monitor the gauge and check for leaks. I don't want to add too much pressure to the system. Any suggestions on the optimal coolant pressure for the system? 2nd question is: Is there a common antfreeze/coolant leak location on the ML350? Any help would be great, thx!
Anthony
Anthony
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From: In the Shadow of the Tetons
2013 ML350 Bluetec
No need to go full bore on the pressure. I'd start at 5-8psi and see what happens. Alternately, you could just put the pressure gauge on the expansion tank and see what happens when you drive around. Leave it on there and see if it holds when it's hot or if it drops back to roughly zero as it should when it gets cold.
Last edited by rapidoxidation; Nov 22, 2024 at 09:06 PM.
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From: CT
2013 Mercedes benz ML350 4Matic
I pumped up the coolant leak kit device to 10 psi while the engine was cold. I wanted to start there but will try driving around with the gauge on as well.
So after about 30 minutes the gauge went from 10 psi to 9 psi. I checked everywhere for leaks but couldn't find anything. I this normal Meaning the very slow drop in pressure over time?
I'm wondering if I should remove all the the plastic shield guards underneath to really check for drips?
So after about 30 minutes the gauge went from 10 psi to 9 psi. I checked everywhere for leaks but couldn't find anything. I this normal Meaning the very slow drop in pressure over time?
I'm wondering if I should remove all the the plastic shield guards underneath to really check for drips?
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From: In the Shadow of the Tetons
2013 ML350 Bluetec
After that 1psi pressure drop, did you start the engine to check for white smoke? That'd be indicative of a head gasket failure - here's hoping there's no white smoke.
Definitely worth pulling the bottom panels and looking closely for leaks.
Definitely worth pulling the bottom panels and looking closely for leaks.
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Joined: Aug 2010
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From: CT
2013 Mercedes benz ML350 4Matic
I will look for white smoke, gotta pull the panels below. i’ve pulled the panels before and found that these particular panels have sponge like absorption pads built into the panels which could technically prevent the antifreeze or oil from hitting the ground so I may have a leak and just can’t see it. It did take about 30 minutes before it went down to nine psi. I’m not sure if when using the leak tester if it should hold pressure or eventually leak out naturally.
