Okay, I have refilled my coolant a bagillion (that's like 100 trillion) times now and every time I have the hardest time getting the air out of the system. Last time I had such a hard time I spilled out nearly as much coolant as I put in trying to bleed the system.
Anyone have any tips to do this more efficiently?
BTW, what is the capacity of the system? Thanks.
A quick and dirty (and I really mean dirty) way to go about this is to pressurize the system by opening up the cap on the expansion tank, taking a deep breath, and pretending that the fill hole is Ron Muthafunkin Jeremy as you blow out and not suck in. You'll have your ears close to the hoses with this method (obviously you'll want the car to be shut off) so you can hear when the air is done coming out of the two bleeder screws but it'll take a few tries before you can do it without laughing at yourself. Ask me how I know.
Oh yeah wash your mouth out with soap after you do that. <------- That's not a joke because the antifreeze is poisonous.
turn the key to the on position but with the car off. turn on the heat as high as it will go, but set the blower to the lowest setting. with the res tank cap on, and the bleeder screw open, wait for air bubbles to stop coming out of the bleeder screw and just straight liquid. close the bleeder screw, your system is now bleed. the high heat and low blower setting turns on the secondary water pump which cycles the system (you will hear it running). IIIRC the total capacity is either 3 or 4 gallons, but Im pretty sure it is 3 gallons.
Not sure if this will work for the 540's, but I jacked my car up on the drivers side(?), held the expansion tank up higher than the engine and filled the system with antifreeze thru the bleeder screw in the t-stat housing until full. Capped off the bleeder screw, put the tank back in its place and started the car and continued to bleed off any air at the t-stat bleeder a few times. Never had any problems after that.
'01 530i Sport(RED)
'90 Miata(work car)
ok...here is what I've done:
I used the following link to change my cooling system:
the guy suggest to drill a small hole in the thermostat (you'll find that suggestion from several sources on the internet). I don't know if is because of that or not but I changed the coolant twice and I never had to bleed the air out and I mean NO BLEEDING AT ALL. I fill the system thru the bleeder screw till is full. at this time the level in the expansion tank shoul be almost to the cold line. top it of in the tank also if is not there. close the system. start the engine and let it run for 10 minutes, let it cool off and check the level in the expansion tank. check the expansion tank after the following drive.
my understanding of this method is that because of that hole in the thermostat the air doesn't get traped into the engine and it finds a way to the expansion tank and it's really easy to take it out of there.
NO MESS AT ALL.
Make sure you have your heater on. In about 10 min and some goosing this should bleed the system.
Yes, I forgot, I drilled a hole in the tstat also.
'01 530i Sport(RED)
'90 Miata(work car)
Thanks for the replies. I will give some of those tips a try. As for drilling a hole in the thermstat, seems worthwhile, I will have to look into that.
Buuump to an old thread.
Just put a headgasket and completely new cooling system on my newly acquired e39. I've always been able to bleed out E36's and E34's with absolutely no problems.
I filled through the resorvor and through the bleeder next to the thermostat. I ran the heater full on, and on the low fan position and had a ton of trouble trying to bleed the system.
I had heat shortly after starting the car, but lost it soon after. I also tired the warm, or "hott" way of bleeding it, with no luck. Looking for any input anyone has.
I also, and always have put a hole in the top of my thermostat.
Thanks in advance for any input anyone has.
I went a year with constantly bleeding the cooling system, because it always had "air" in it. It kept getting worse and would start overheating and losing heat. I had a cracked head that was letting exhaust gas into the cooling system. If your cooling system is still pressurized after it is completely cold, then have this problem checked out.
O.K. you guys are close. Pull a return hose off that is higher then thermostat and fill coolant resorvor when engine is cold .This will push out air pockets. Start and test drive. turn heater on and make sure you have warm air coming out. let cool and top off resorvor.
My method (it works 100% of the time):
- Engine should be cold or warm (not hot). Don't start it yet.
- Put the front of the car higher than the rear (ramp, jack, hill). This will force bubbles/air up front.
- Turn on heater to max temp, and any fan speed you like (it doesn't matter).
- Open the hood, remove expansion tank cap and loosen the bleeder screw.
- Start the engine.
- Start filling the tank with coolant up to the very top, you will see that as soon as it reaches almost the neck of the tank, it will go down a bit. Add more, and repeat. Because the car is circulating the coolant around the system, you'll have to keep adding and it will keep going down for a while, be patient.
- While you're adding coolant, keep an eye on the bleeder screw (remember it should be already opened). Coolant and bubbles will start flowing out of it.
- Keep adding coolant to the tank until you only see a continuous stream of coolant coming out of the bleeder screw. It will happen at some point, don't close it before.
- When you're sure no more bubbles show up, quickly close the bleed, put the radiator cap on, check if hot air is coming out of the interior vents, unlock your OBC and check the temp (shouldn't be over 115 C on an I6, mine stays at 94 C).
- If at some point a fountain of coolant comes out from the reservoir, it means you let the engine get too hot and you need to wait for it to cool down and repeat the process.
- If you can't feel the heater working, there's still air in the system.
That's it. Do it step-by-step and you'll have a fully bled cooling system. After a few days the coolant level may go down a bit, just add to the mark in the morning when the engine is cold. An additional note: My 528i has two bleeder screws, one on top of the water pump and another just next to the reservoir. I only use the former, the other is not really necessary, keep it closed the whole time. AFAIK V8s only have one.
Last edited by crdiscoverer; 12-22-2009 at 09:24 PM.
Resident Third World Country Advisor
I been fighting this issue for 3 weeks. I will try your method!!!
(saved to .pdf)
Thank you guys so much for the input. Im going to drain the system and try again using the method's listed here. I can't wait to be able to drive the e39 to work!
Well, I think I've got the cooling system bled.. and I took it for its maiden voyage and it did great until almost home and it started missing and then wouldn't run anymore. Im pretty sure its the fuel filter though. The car has been sitting for over 2 1/2 years.
I ended up draining what I could out, which wasn't much.. Then jacking it up as high as I could. Filling it through the upper hose, then through the overflow and then started it and let the air work out. Did that for a while and then drove it about 20 miles until the next problem occurred. Its all good though.
Last edited by HE53; 12-22-2009 at 11:31 PM. Reason: Automerged Doublepost