Coolant leak (sensor)
#11
If there is no one that knows the size of the o-ring, be patient for a week. I will pull mine out and measure. I am going to decommission this car and drive my convertible Dec-Feb so in about a week and i'll have time to do it.
#12
Members
Joined: Feb 2012
Posts: 15
Likes: 0
From: shanghai, china
My Ride: 2004 525i
Model Year: 525i 2004
Engine: M54
#13
Members
Joined: Feb 2012
Posts: 15
Likes: 0
From: shanghai, china
My Ride: 2004 525i
Model Year: 525i 2004
Engine: M54
here comes the sensor size
here comes the exact O-ring size data. i had to buy a new coolant temperature sensor the other day, and it arrived just now. the first thing is measuring it. the outer diameter is 14mm, and the thickness is 3mm, so the central circle is 8mm.
the new sensor:
now the old one(i borrow it from another thread):
the new sensor:
now the old one(i borrow it from another thread):
Last edited by daweilee; 12-04-2012 at 12:54 AM.
#14
Members
Joined: Feb 2012
Posts: 15
Likes: 0
From: shanghai, china
My Ride: 2004 525i
Model Year: 525i 2004
Engine: M54
to get long-lasting effect, i think , maybe 14mm(whole diameter),3.5mm(thickness) also work, and better.
Last edited by daweilee; 12-04-2012 at 12:55 AM.
#15
Thanks. I bet its the same exact o-ring I had on my instake camshaft position sensor. It came with an extra o-ring so hopefully it is. Looks the same and BMW always uses exact sizes in other parts.
#18
New Members
Joined: Aug 2013
Posts: 41
Likes: 0
From: Colorado
My Ride: 2007 BMW 530xi, 3.0L I6, 6-spd Automatic, 255 hp; 2011 Chevy Camaro 3.6L V6, Direct Injection, 6-spd Automatic, 312 hp
That might be where I'm losing coolant, getting a low coolant warning every month, 07 530ix
#19
Senior Members
Joined: Mar 2011
Posts: 1,198
Likes: 3
From: Boston
My Ride: '06 530i, '07 C280 4matic, '98 ML320
Radiator itself can leak as well. Only way to be sure about the source of the leak is to actually look at the above mentioned parts.
#20
New Members
Joined: Aug 2013
Posts: 41
Likes: 0
From: Colorado
My Ride: 2007 BMW 530xi, 3.0L I6, 6-spd Automatic, 255 hp; 2011 Chevy Camaro 3.6L V6, Direct Injection, 6-spd Automatic, 312 hp
Temp sensor gasket is ONE OF the probable source of the leak. Take a flash light and check around all coolant hoses (especially the return hose on the top where it connects to radiator), and the coolant tank. Look for coolant residue around the connectors.
Radiator itself can leak as well. Only way to be sure about the source of the leak is to actually look at the above mentioned parts.
Radiator itself can leak as well. Only way to be sure about the source of the leak is to actually look at the above mentioned parts.
Edit update: I just checked with a flashlight, yeah a lot of rubber hoses/connectors, no seepage/leaking seen. ...Just an annoying coolant level warning every month or two. I'll keep adding a 50/50% mixture and grumble.
Last edited by Car_Almond; 05-14-2014 at 09:53 AM.