whats best way to bleed cooling system 3.0??

[fire2]

Ive done the searches and cant make too much sense of bleeding my system. I got air in it after draining the system and now heater is not working that great, it just gets a little warm. From the searches the best that i am seeing is i need to remove the filler cap and squeeze the hoses while keeping the resovoir toped off untill all the air is squeezed out. Is that the best and/or easiest way.....or what is??

[Z3RO 2 6T]

Right next to the cap where you fill with antifreeze is a small cap the size of a dime. Use a flat head and unscrew it. Rev the engine to get the fluid pumping and air should come out with some coolant also. After I did this my heat started working. Hope that helps.

[BladeAZ]

Bentleys says to run the heater during the bleeding procedure, also.

[Robstah]

It helps to jack or ramp the car up in the front.

[fire2]

Right next to the cap where you fill with antifreeze is a small cap the size of a dime. Use a flat head and unscrew it. Rev the engine to get the fluid pumping and air should come out with some coolant also. After I did this my heat started working. Hope that helps.

Thanks Ill try that........im assuming that you open the small cap when its cold? do you keep it open till the engine warms up?

[Z3RO 2 6T]

I put the heat on full and did this while the engine was cold. I let it run with the cap off for a few min and reved it a few times inbetween. Also make sure u have coolant in the tank.

[fire2]

Ok, i ran it and reved it up, but coolant would keep bubbling out of the hole untill i let off and then not enough coolant in the tank. is it sucking air back into the tank when i let off??.........I only see a few bubles come out when I did this, now maybe just slightly more heat. How long do you have to do this and how do you keep coolant in when it is constanly coming out?

[McKinneyWhiteM3]

if you're short on coolant, the tank is dry and you're introducing air back into the system. when the coolant starts flowing, you need to keep topping the reservoir off as the coolant gets sucked away.

when coolant starts to spill out of the hole, screw the small cap back on, check the coolant level one last time and replace the reservoir cap.

coolant comes out unless you plug up the hole. the whole procedure should only take a few minutes after the engine is warmed up.

[Z3RO 2 6T]

Thats why I said make sure the tank is full. If its empty it might suck air in like he stated.

[MCoupeVet]

Right next to the cap where you fill with antifreeze is a small cap the size of a dime. Use a flat head and unscrew it. Rev the engine to get the fluid pumping and air should come out with some coolant also. After I did this my heat started working. Hope that helps.

Bentleys says to run the heater during the bleeding procedure, also.

I put the heat on full and did this while the engine was cold. I let it run with the cap off for a few min and reved it a few times inbetween. Also make sure u have coolant in the tank.

Thats why I said make sure the tank is full. If its empty it might suck air in like he stated.

All true statements. Keep doing what they say. Air and coolant will bubble/spurt out of the bleed port. Keep it up untill you get maximum heat out of the heater system. Its scary, but it works. Dont forget to put in the antifreeze.

[Ratman27]

Just finished changing my waterpump/thermostat. The Bentley manual helped me get the parts changed, but this article got me running again.

Thanks to everyone who posted replies to the OP.

[JoshS]

It helps to jack or ramp the car up in the front.

Not a good idea on a 3.0 (or any M52tu/M54). The overflow reservoir isn't at the front of the car.

EDIT: just realized this thread and the post I replied to is old ... sorry about that!

[dmytro]

Something I read somewhere that works. Get a spare plastic bleeder cap and drill a hole in it to snugly fit a clear plastic hose long enough to reach the other end into the reservoir submerged. Sit in drivers seat with engine running and see bubbles move along clear hose. Rev engine to make bubbles move faster, but if the end is submerged it will not suck air back in when you back off.

[Isolatos]

I am a new Z3 owner. I replaced my thermostat today and did a reverse flush on the system(work equipment). My heat works awesome now-the stat was definitely bad. My only issue is when the car is warm and I stop(with car running) for a couple minutes the hot air becomes warm and then cool. As soon as I rev it or start moving it is hot again. Is this normal for the 2001 3.0i roadster? After connecting the upper hose I did start the car and left the bleeder open for a while. Thanks

[Racerman27410]

does your car have the electric thermostat ? i wonder if the computer does that to keep the engine temp in the correct range via sacrificing interior heat ?

[K1CKBAC]

Strange, I didn't do anything to bleed my cooling system when I changed thermostat and water pump. My system is a self-bleeding system. M54 in my car.

[Isolatos]

I was surprised that the thermostat cost so much until I saw that it came with the housing. So I guess it is computer controlled. Do you think I need to bleed the system again?

[KBH22102]

I know the Bentley says this is the M52-but I didn't see it on my M52. Maybe the M54 has this extra bleeder screw so you don't have to raise the front of the car to bleed it?

[Isolatos]

Mine doesnt have that one. I know on my E30 I used to raise the front to bleed, but my resevoir and bleeder arent in the front of the Z3, they are near the strut tower, Ive read that there is no need to raise it.