What does "bleed" mean?!?! How do you do it?
LOL...did anyone mention the bleeding procedure?
Originally Posted by uscharalph
95 E34 530I V2.37
===========
Those who make peaceful revolution impossible will make violent revolution inevitable.
John F. Kennedy
What does "bleed" mean?!?! How do you do it?
To bleed is to remove air from the system. Air prevents movement of the coolant/water mixure, thereby hindering cooling.
On the M30, the bleed screw lives at the top of the thermostat housing. It's pretty close to the highest point in the system, hence pretty much where air congregates. When filling a system with fresh coolant (be sure to use BMW Cool Blue, other/generic coolants are suspect), the bleed screw should be cracked open to allow the air to escape. If it's not, air stays in the system. Some air will be in there (maybe even trapped in the thermostat cover) regardless, which is why it needs to be bled out with the car running. With the expansion tank full and the cap off, start the car and open the bleed screw. Close it when a steady stream of fluid comes out, no air. Actuate the throttle and look in the expansion tank -- check for a steady stream of coolant returning via the pisser. No stream? Bleed some more, actuate the throttle some more. Don't overrev a cold engine -- keep it somewhere below 3k rpm. Once it's pissing, close the expansion tank and start driving the car/watch the temp gauge. An 88 degree tstat should keep the gauge at 12o. If the gauge goes above that, pull over immediately and bleed it -- if air comes out, get it all out. If coolant comes out and not air, shut off the car -- there's some other problem.
Also, the heat should be on high/full blast throughout the entire procedure.
Also, there's a good chance that the tstat itself, among other things, is fried if the car has been overheated.
The M30 isn't hard to bleed. I used to think it was a major pain in the ass.
best, whit
Last edited by Kalevera; 10-29-2005 at 05:49 PM.
Crap...my mechanic put in generic coolant, I think it's blue though. Should I drain it? Also, just to double check, by "expansion tank," you mean the tank where you actually pour in the coolant, right? Does anyone have a picture of a pisser?
Thank you so much
the pisser goes from the expansion tank forward to the radiator.
95 E34 530I V2.37
===========
Those who make peaceful revolution impossible will make violent revolution inevitable.
John F. Kennedy
"expansion tank," you mean the tank where you actually pour in the coolant, right?
That's it!
Ralph Mendoza Jr. - Long Beach, CA
Thanks a lot guys. I very busy during the week but I'll try to bleed it during the weekend and tell you how that goes!