How to check coolant and Bleed air from Radiator and Engine M3 M5 E36 e38 e39 e46 e53 e90 e60 

You should use the AUX water pump for filling, makes it a lot easier and faster for coolant to come out the vent hole on the thermostat housing. Open all the vent screws and fill the exp tank full. Turn ignition on but not the engine, set heater to max and blower to min, this sets the AUX pump to work, start filling, coolant will go all the way to the top of the exp tank but continue filling all the way until coolant comes out the vent hole on the thermostat housing. Wait until bubble free coolant comes out. Screw it back in and see if coolant emerges out the radiator vent screw, then screw it in. Now the engine is filled, to bleed the system, start the engine and give it a go up to 4000 rpm 3-4 times and the engine should now be bleed completly. Do not run engine for longer periods. Screw back on the main cap for the exp tank, you should leave 1.5 inches up to the cap of air so that when the coolant expands first time it wont overfill. After some heat cycles and thermostat openings coolant will drop slightly as remaining minimum air bubbles will be expelled into the exp tank. Voila. THis is the correct BMW procedure.

Thank you, Nathan! Awesome being able to come here for all the right answers! Just finished topping mine off. And, to your point, I had an experience a year ago where my car overheated and it probably cost me some life in the miles on the car. I now have to put additive in the oil so it doesn't leak.

Tried this earlier and it worked like magic! Thank you so much for your video.

Thnx Nathan I just bought a 2002 e39 and I love watching your channel to keep my car running regular and maintained.

Thanks Nathan this video is my life and my car's engine life saver. I installed an lpg kit few days ago and it required me to cut the coolant hose behind the head to feed the lpg reducer. After watching your video i was able to re-bleed the system properly.

Thanks nate! Finally solved my 97 bmw 528i over heating issues with this video. I was under filling my coolant. I was using only 2 gallon when in reality it takes 3 gallon to fill a completely empty systems after a coolant system overhaul water pump, hoses, and radiator.

Just helped me fix my overheating problem. Thanks so much.

Thank you. I only thought to open the one screw. It keeps being empty in the house of the thermostat. Going to do that now and check back

Thank you nathan I followed this procedure and was able to complete my diy fix of replacing a coolant hose.

Great job! Thanks for helping us!... And no cussing!

Thank you so much for sharing this. This was really helpful to me with my 528i.

Thanks Nathan, you are the only person I turn 2 when I need e39 advice, and it worked perfect. Cheers mate

Very helpful and simple. Thanks for getting right to the point! Keep making videos on all the DIY for the E39. Thanks for your time!

nice video! I do it slightly different on my E36 but I will try your method next time.

I'm doing it today thanks Nathan from Australia entering summer👍

Nice job Nathan. I wish I saw this yesterday.

Thank you Nathan you always come through for me

hey nate great video, you are a lifesaver when it comes to working on my e39! I have an issue right now with the bleed screw that comes from thermostat is corroded on there serious haha, any suggestions on getting that out so I can bleed the system? again thank you for being really thorough with your vids!

Thank you so much! You saved me a whole lot of money and headaches! Great video and very informative. A+

Can you do it without the heater. So fill till it pours out bleeder valve then turn car on and make sure the filler cap part is full?

Can I use the same procedure for my 2001 E38 740IL? I only see one bleeding screw.

My friend, I disconnected the coolant level sensor plug, but it still shows me check coolant level, what is the solution?

Muchas gracias hermano, me ayudó mucho.

Hi Nathan, I am owner of an E39 523i Luxury pack, and I have a problem with my cooling system, am losing coolant from the pressure releasing poiny next to the expansion tank everytime I start the the engine since a few days... I also noticed I screwed up the two bolts on the air releasing points

Hello Nathan, Thanks for all your great videos, I've been watching them closely. Sadly I've kept having heating problems after changing Auxiliary Pulleys, Fan Clutch,Thermostat and Coolant (system properly flushed and bleed) and making sure water pump is working fine and there are no leakages. Can't think anything else... Any thoughts or suggestions? Rich

I ve got bubbles and fluid busting out. How can I troubleshoot to figure where this pressure is coming from

Hello my friend, the check always shows me the check coolant level, although everything is correct, could the defect be from the same sensor as the bme x5 e53

@Nathans BMW Workshop so on an e53 X5 you take bleeder screw out put heater on key position 2 so coolant circulates and keep topping up till it comes out bleeder screw hole put screw in then top up resovoir until it's at level?

I've followed your video on how to bleed the cooling system and after about 20 mins of driving my temperature gauge starts moving passed noon to about 3/4 mark. I've replaced the thermostat and water pump about 2 1/2 weeks ago and everything was fine till I ran my ac and I have had nothing but issues since. Don't know what I should do, the upper hose of the radiator is hot and the lower hose is cool to the touch

I am attempting a refill. The coolant did get too low. The previous owner did epoxy the bleed screw shut. So I ask, is there a way to do a bleeding without that until I can get a proper radiator piece replaced?

My e39 would got very slowly hot. Do to too low coolant level in the engine. Learned the hard way as it began overheating and didnt blow hot air the cabin. It rarely went to 90 degrees before, but now it's fine. I checked the thermostat, pump, hoses and radiator. I had to force the engine to even want the cooling i gave it. Blew air in the, reved it, had it on incline etc. Filled when it got low and stopped when it stopped and got hot air in the cabin. Hope this hope somebody else. These engines are a pain to hold air.

How do you know if you overfill it ? When you open the cab and there’s a lot of pressure the next day ?

Hi If you replace with new all the cooling system components on E39 528i 1998 M52 engine and you don't see coolant mixing with the oil.... And you have rock solid hoses, what's would be your suspect for this. BMW dealer here in UK is telling me this is normal but they are exceptionally hard can't squeeze them? When I drive temperature is solid 94C but idling goes to 102 and looks coolant doesn't circulate proper thru the radiator to activate the viscous clutch /fan.

How are you doing you have a BMW X5 e53 3.0 having a problem with overeating what could cause

This common failure should be in BMW's brochures. Right next to the valve cover gasket oil leaks.

Hey Nate...my E46 has a fully rebuilt coolant system. The head gasket is fine. No bubbles when cap is off and car is running. But...it builds up pressure and I can't remove the filler cap without loosening the bleeder screw. It's like it has a blown head gasket but the leak down test, block tester kit, and compression test checked okay. It doesn't overheat but like I mentioned before it has a lot of pressure in the upper hose and it's annoying driving around wondering if the hose will pop off or split. Not my daily driver but I wish it was. Any help would be appreciated. Oh and I've bled the system 20 times the way you said. Still have no clue why its doing this. Message for more details

Differences of bmw e39 triptonic, engine made in singapore and europe???

How warm do you let the car heat up before shutting it down and waiting to cool down again? to its normal running temperature which is at the halfway of the gauge?

Hey nice video it helps alot i have a 1995 bmw 740 il i have 1 problem in the dash board i cant see my miles or anything i dont know if its a sensor or idk can u help

Did you say you have to do this weekly?

Im haveing an over heating problem do you think air is getting in the system ive removed the thermostat and replaced water pump i do know my electric fans are not working so maybe that could be somthing to do with it but before it started i dont remember them being on all the time.

Great video I have a 1997 BMW 528I replace the thermostat and housing fan clutch and water pump and it’s still overheating. When I drop the oil it was not mix with water so I don’t think it’s the head gasket any ideas

Thanks for making this video

Is my radiator blocked..my coolant tubes under intake on 01 bmw m54 keep cracking/leaking.?

Hey dude what if it is shooting out the coolant tank? E46

What can I do to stop the bleed and put on new bolts !???

Question man need help from someone I had a bad water pump and thermostat change them out and now every time I try bleeding out air bubble I take off 2 bleeder hole and coolant reservoir cap water gush’s out of the thermostat hole but if I put close reservoir cap and the bleeding hole next to it and I leave the thermostat hole open water doesn’t gush out

I have a problem with my 2003 e39, I added coolant but I don't think I bled it correctly and now my service engine soon light went on and the car is idling rough. I've tried to bleed the system again but no air comes out, only coolant.

Thanks I needed that help

hey nathan. the pump that is supposed to be running when you turn ignition on without motor on is not working. how do i bleed it?

thanks, very clear.

What if I don’t have bleed screw

Hi Nathan, I followed your bleeding process for my 98 e39, but after I started the car, the coolant in the reservoir did not get sucked down. What could be the problem? I also noticed that the water slowly rises in the reservoir as the engine warms up. I performed the test where you turn the car on (no start), heater up, press the gas pedal for 20 secs then let go. No coolant was spewing into the reservoir. How long does it normally take before the coolant starts spewing into the reservoir?

Hey nathan on my e83 N52 engine My coolant fitting broke ,after that the top coolant hose broke then the coolant over flow cracked. I replaced the parts but after filling it up and doing this process now is acting up, it shuts down on me. Noticed the overflow tank cap was kinda condensing along the bottom of it. You Think its stalling because of pressure or that tank sensor idk can you guide me a bit?

My antifreeze is blue, should replace it with blue or change it?

No need to bleed from engine?

2 the point 🤟🏿...thx 💯

Hi great video i have a problem with my e53 once topped with coolant amd no visable leeks within a hour it says check engine coolant again!! Please help

My car is rocking it out what issues can it be some one said mabe stuck thermostat

Nice video but if you overfill will it overheat ?

Hi there Nathan. My e36 is making like you said 4.26 - 4.30 its like boiling out a im losing coolent and because of that it started to over heat. that happened the past sunday and i figurred i should search your videos and ask what might be the issue?

What if bubbles keep coming out?

The best way is to blew thtro the radiator filer hole and thai way ir bleed instantly

if you dont bleed the coolet system can it cause a coolet leak

not bleeding the coolant system cause it to have low coolant level???

Hello Nathan I am having a problem on my 99 528i the housing on the rear coolant hose that goes in the rear of the engine is broken and coolant is pouring out everywhere I don't know how to get to it to replace it can you please help?

Ok I just purchased e39 Machanic special pit new expansion tank pullys drive belts I I bleed the system should probably do it again with heat on like you said but I do have heat now after repairs the temp sits rite straight up in the middle of hot and cold can you tell me if that’s normal for my temp gage to be showing exactly in the middle ????? I would super appreciate any input as I never owned or driven a bmw until now so I’m not sure where the gages sit

Hey Nathan I change the radiator I change fan clutch and fan the water pump it still good and I change the thermostat but it still heat up all the way to red I don't know if it's the thermostat that is defective but Imma get a new one tomorrow morning and see if it's that can I put any coolant or do I have to put BMW coolant 50/50.

4:28 "Coolant rocketing out" - Hi Nathan, this is exactly what is happening on my M54 x5. What is that a symptom of? I have a leak that I can't find.

Sir i did a coolant flush on my 01 bmw x5 3.0i. I flushed the old coolant out of the radiator. After i refill just water and reflushed until the water turned clear. I use the bmw oem coolant which recommends to be mixed with water 50/50. I have seen other videos who has done this. Put the concentrated coolant first and after the water. Which i did the same procedure. But when i get to the part of putting the coolant in after last water has been flushed out. The radiator is quickly filled up with just 1 full gallon of concentrated coolant. I was not able to add any more water as supposed that i should to get the 50/50 mix. Did i do anything wrong some how? Thanks for you answer!

Hey Nathan. I have an issue with my E39 1996 520i. Last week i found out that the hose from the tank to the thermostat was very warm. And the hose that goes out from the thermostat and back to the radiator was cold. Even after a long ride. I thought it was the thermostat, so I changed the thermostat and the water pump. It's not leaking either. I bled air from the system, as I have done a million times, and the problem is still there. Am I right that the hose from the thermostat to the radiator is going to be warm aswell. Do you have any ideas what it can be? Best regard, Christian.

Thanks Nathan great video as always. Just a quick question: on my e36 320i, if I take off the coolant cap when the engine is cold (say first thing in the morning), I always find the coolant level is way down to around 1/5 full in the bottle. However, sometimes if I leave the cap off for a moment, the system makes a gurgling sound and the coolant comes flowing into the bottle up to the cold mark. The car runs fine and doesn't overheat (it's well and truly Summer here in Oz at the moment). Any thoughts on what could be causing this? Air in the system maybe? It doesn't appear to be using coolant because whenever I check it every week and it does the gurgle thing when cold, the coolant always comes back up to the proper level. Any thoughts much appreciated. Thanks.

So in my e39 the float thing is about half way down in the bottle, do i have to bleed the system or is it okay just to fill it up?

Hello how long do you think this should take. It’s been an hour and a half and I still see bubbles coming out?

you should have the *Blue* coolant.

When I take the radiator cap off, the coolant overflows. What could this be ?

Do you need to do a 1:1 mix of coolant and distilled water?

My thermostat doesn’t have a bleeder. It’s 100% locked

Hey can't you. Over fill the e46. Causing overflow tank to crack?

do i really have to use bmw coolant?