Loud Whirring Sound
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Member
Joined: Sep 2016
Posts: 113
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From: San Diego
2002 CLK 430, 2005 CL600, 2009 Smart Fortwo
Loud Whirring Sound
Hi folks, I had the high pressure expansion hose blow on my car, I was unable to pull over safely and shut down right away. I had my pump rebuilt out of an abundance of caution since it is so difficult to get to. I wound up replacing the HPE hose, the hose to the right front line to the strut and the high pressure line also because of the difficulty of doing this repair. I have it all back together and the system is working fine but there is a loud whirring sound which varies with engine speed. I suspect either air in the system or failed pulsation damper or both. I am wondering if I will do any harm driving it in hopes of working the air out. I have cycled the abc vehicle raise-lower button maybe 10-12 times in hopes of getting the air out. Does anyone have opinions? My car is actually a CL600 and I posted this on that forum and got no answers so I thought I would give it a shot here. Thanks!
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Joined: Jan 2008
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Mercedes
Yes it’s air in the system or pulsation damper . Did you fill and pressurize the abc reservoir with compressed air , and turn the front wheels lock to lock 30 times while they are lifted in the air on Jack stands ? That’s what you must do after replacing pump
Thread Starter
Member
Joined: Sep 2016
Posts: 113
Likes: 24
From: San Diego
2002 CLK 430, 2005 CL600, 2009 Smart Fortwo
Yes I did prime the pump with compressed air and it did work. The car will raise and lower in response to the button so I know it's primed. I don't know about turning the wheels back and forth, the power steering fluid circuit is separate from the ABC circuit.
MBWorld Fanatic!
Joined: Jan 2008
Posts: 6,150
Likes: 533
Mercedes
Yea but you replaced the pump which is a tandem pump for both systems . Lifting the front wheels and turning them 30 times is so crucial after pump replacement many pump rebuilders put the warning sticker right on the box
