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Old 10-13-2012, 11:19 AM
Larrick Larrick is offline
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Location: Berkeley California
Join Date: Sep 2009
Posts: 1,140
Mein Auto: 1994 525it
There are no bubbles in the expansion tank.
The reason that I used a slow running hose was that I was getting tired of hand feeding water every minute or less.
The bleed screw was removed and the rad cap off. Coolant flowed from the bleeder hole with massive amounts of bubbles.
This was endless and the bubble consistency never changed.
The expansion tank needed constant filling or the bleed hole became "dry" and only steam or nothing came out.
I feared that if it were not constantly toped off that air may be being sucked back into the system.
The top hose never felt "full" to me but I do not know how it is supposed to feel.
There is no apparent leak to account for lose of coolant.
Perhaps more coolant was lost in the initial overheating than I know of but that should not matter once it is refilled.
I bled the engine for over 1 1/2 hours.
The engine does not overheat at idle and the temp needle sits at 1/2 or a needle width above or below 1/2 the entire time.
The test procedure the My525it describes is for engines overheating at idle. Mine does not.
I am confused about the fan clutch. My fan comes on immediately and remains on.
The fan clutch seems fine. I did the newspaper test and it stopped and then stared again.
While cold it moves with a little resistance as described in Bentley.
I will start it again and see how long things take to heat up.
Last time the needle was just below 1/2 after 15min. and the top hose was slightly warm, bottom hose was cold.
Bottom hose warmed at about 30min.
The HG test sounds interesting.
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