E90 Breether Screws Warning Everyone with E90 Should read (updated with Pics)

[Dippies]

Well the Best way to explain this will be to start from the beginning.

On Friday i Took my car to Powerflo in Edenvale where i did DP and Software by Promotec.

While i was waiting patiently i grabbed to opportunity to inspect the undercarriage and looked for possible leaks.

Glad to report that i found nothing, no Leaks what so ever and even the guy sorting my DP said its one of the Cleanest Diesel Engines he has seen.

So after completion of the Dp the car was lowered to put the Engine cover back i inspected the Engine bay for some leakages and or visible Oil leaks cracked pipes and so forth.

It is then that i noticed that there is White Spatter on some of the pipes around the Water reservoir. The White spatter was due to the Antifreeze. Everything seemed fine and i collected a Piece of Cloth from the Boot and Cleaned the Pipes to c if this was occurring often or if it was a one time occurrence.

Software was done and i drove back to Centurion.

Everything was fine and supper exited with he new tune.

I took a short trip to the shops and back to my house.

I noticed that there was water dripping from my Bonnet area. Immediately concerned opened up the bonnet and saw that the water was dripping from the Reservoir tank overflow/Breather Screw. checked the OBD to c if any errors occurred that i missed ( Got a Yellow Engine Warm light the same as Jerry's aka Jenich Car) So i waited until the car was cooler and opened up the Reservoir tank for a Possible Solution to the problem and why it was pushing back the water to the reservoir tank. ?

Possible reasons 1) Water pump Failure. 2) Thermostat Failure. 3) Airlock.

Well it was simple to test the Water pump as i knew the bleed procedure of the Electrical pump. so that would eliminate the problem to Thermostat and Airlock. But another problem surfaced when i tightened the Bleeder screw on the Reservoir tank and had a "technical malfunction" Broke the screw off in the tank :facepalm: . I Left the car overnight. Worried the evening i came up with a plan to get the broken Screw out of the Reservoir tank.

But i would need a replacement Screw and Guess what ONLY BMW had the part as i searched all over. So off to Leohease I went. upon Arrival i spoke to one of the sales people and asked for the part (Breather screw)He said sorry Parts is closed on SATERDAYS. I asked if i could speak to one of the technical people. Willie came to greet me and escorted me through to the parts section. I confirmed with him the Bleed Procedure for the E90 320d 2007 model. He said i was correct and pointed out that not all the 4 cylinder cars came out with a electrical Waterpump. :argh::thinking: but the E90 does not have Bleedscrews except for the One on the reservoir tank. :fencelook:

Wrong again Luckily the Guy showed me where my Bleed screw was and pointed out that it has one screw was located on top of the thermostat housing. According to the diagram i saw two Bleed screws on the Cooling System. I got a Part from the technical guy R53.50c for the Bleed screw. Also got a Quote for the Thermostat if i found that to be the problem part. R800 mandelas. I Picked up some Antifreeze from Midas to fill up the Cooling system.

So back home i went and started thinking about solutions on how to get the Broken Screw out of the Reservoir tank.

I took a Candle and heated one of my screw drivers. careful not to damage the reservoir started to melt the screw driver into the broken off piece of screw. Success it worked like a charm. The broken Piece got out and i now needed to get back to testing the cooling system by means of eliminating the problems.

I removed the Covers to get to the Thermostat housing and location of the one Bleed screws, and opened it up careful not to damage or brake this one as well, proceeded to open the one from the reservoir tank as well. Filled up the reservoir to the max capacity and made sure all the air was out of the System.

NOTE: The Fan will not Kick in if the cooling system has an Airlock. CONFIRMED IT WITH THE TECHNICAL GUY AT BMW.

So I also learned previously on my Father in laws 5series BMW that BMW needs to be ice cold before you attempt to get rid of the AIRLOCK.

So I filled up the reservoir and bleeded the system inspected all the pipes for any leaks of water. i then noticed another Bleed screw :argh::nonono: ai jai jai so to confirm the E90 320d 2007 has three Bleed screws.

1) situated on the reservoir

2) situated on top of the Thermostat housing

3) one situated on top of a pipe directly above the alternator.

So i Bleeded the system and confirmed no air bubbles out of all three Bleed screws. closed all Bleed screws made sure not to tight as they are plastic and brakes or cracks easily.

Then Started the Car. Left if Idling for about 15 min. Waiting for the fan to come on to c if the Thermostat opens and the water circulates, and if i still get the yellow light indicating engine is overheating.

So after the 15min the obd shows no errors and i constantly confirmed no leakages on the Cooling system. After the Fan came on the water circulated and everything seems fine now.

Closed all the covers and parked the car, I will take it for a test drive later to confirm everything is sorted now. In the end the one Bleed screw on top of the Water reservoir was the problem as it was not closed properly and the water escaped through there when the engine got hot. Luckily it is sorted now :joy:

So lessons learned E90.

1) If your system has a airlock The fan will not come on and your engine will overheat. (take caution as i did not drive my car till i got a Red overheating symbol on the OBD) i switched off immediately when the firs yellow symbol was shown.

2) Those Bleed Screws are made of plastic take great care as you tend to over tighten them and they brake or crack easily.

3) BMW is nicky when it come to cooling system - if the engine is not cold when flushing or bleeding the Cooling system it will create problems for you. Seen this now on the E90 and 5 Series.

4) Bleed Procedure for the Non Electrical water pump is easy enough. Open all the bleed Screws fill up the reservoir until all air is out of the system and then start to close all the bleed screws from the furthest away from the reservoir.

5) Take great care when handling or tightening the bleed screws and confirm no water is running out when you start the car. This was initially what caused my airlock in the cooling system.

6) never expect what you did not inspect.

So to confirm that the E90 320d has in fact got three bleed screws and not like previously indicated in other threads no Bleed screws.

I will update the thread with pictures later during the day.

I hope this serves as info as i could not find a single resolution to my problem and bleed procedure for 4 cylinders cars that does not have a electrical water pump.

Please commend and or share your experiences. sorry for the long post.

Dippies

 

[S1NGH 001]

Thanks for sharing this important info with us :thumbs:

Glad it was nothing major :=):

 

[prado]

Thank you! I recall asking about the bleeder screws on Jenich's post some time ago - I posted some pics of my 5 series bleeder screws.

I was a bit confused after that post as I 'learned' that the 320d did not have bleeder screws!

Anyway, I feel a bit more 'learned' now! :thumbs:

 

[Solo Man]

About four years ago i also broke one of the bleeding screws on my E39 528i 1998 model and had to get one from the dealers. R42 iirc and was shocked at the price! I was thus pleasantly surprised when i had to get four "pushbutton expanders" (for lack of correct term), that holds the airduct cover on the E46 328i 1999 model for R5.43 each from the dealer.

 

[Sabretooth tiger]

Glad you came right bud. Nice write up.

 

[Pfw28]

Many thanks for very important info, wonder how many sleepless nights will be saved! Also broke off a bleed screw a while back, on an E36 325, R 42 odd from SMG in Pmb. It seems that they get brittle with age, same as the plastic hose fittings, of which I've changed many. Glad it's sorted, and without selling your home. :thumbs:

 

[marcus d90]

My stepdad broke a bleedscrew on my mom's e46 318i, it broke easily, it must get brittle with age and heat. I broke one on my wife's mg, even the new one broke easily.
On landrovers we have the same problem, solution, brass nuts, the first mod to do.
Mine now has a brass nut on the radiator and thermostat housing, no problem.
These are however much bigger than on a bmw, but i am sure that brass nuts will work on bmw cars just as well. Currently i don't want to fiddle with my e90, i broke the top part of the new rear shocks i fitted two weeks ago, it broke off like nothing.

 

[Dippies]

The trick Comes in to Turn it until its closed without forcing it.

Will upload the pics tomorrow as i did not have a change yet to take some sorry

 

[Dippies]

:bump: for those who have not seen it yet.

 

[johandl]

This post comes with perfect timing, thank you very much! My wife just called to tell me the petrol attendant had accidentally messed with the breather screw and broke it off whilst looking to open the cap to top up the water of our 320i (e90 - 2007). Not sure how why he messed around with it exactly, but needless to say water poured from the tank.
My wife drove off, but heard a 'grinding' sound, and thinking they messed up during the oil top up, turned back to Total in Melkbosstrand to check with the manager what was done.
This is when the screw was discovered. However, Im unsure why that would cause a grinding sound, so here is my main fear: could they have first topped up the oil tank with water before realizing their mistake?
Total has offered to fix the screw, but my concern is the 'grinding' sound that was not there until after this incident. How do I force them to look at that and accept responsibility if they did make such a mistake? I want them to do an oil change just in case, but I have no proof since I was not there.
What a mess! And the car is on -+109,000km so just out of motor plan

 

[Rompsku]

Very informative. Like that last lesson (number 6) too...

Glad you got your baby sorted.
Kinda worrying that the BMW techies don't know their stuff though... hmmm

 

[Mike1]

Great info and write up! :thumbs:

 

[Dippies]

This post comes with perfect timing, thank you very much! My wife just called to tell me the petrol attendant had accidentally messed with the breather screw and broke it off whilst looking to open the cap to top up the water of our 320i (e90 - 2007). Not sure how why he messed around with it exactly, but needless to say water poured from the tank.
My wife drove off, but heard a 'grinding' sound, and thinking they messed up during the oil top up, turned back to Total in Melkbosstrand to check with the manager what was done.
This is when the screw was discovered. However, Im unsure why that would cause a grinding sound, so here is my main fear: could they have first topped up the oil tank with water before realizing their mistake?
Total has offered to fix the screw, but my concern is the 'grinding' sound that was not there until after this incident. How do I force them to look at that and accept responsibility if they did make such a mistake? I want them to do an oil change just in case, but I have no proof since I was not there.
What a mess! And the car is on -+109,000km so just out of motor plan

If they opened your bleeder screw and the car was still warm (not Overheating but normal Temp) that will cause a Airlock right there.

The water will Spew out of the breather screw when normal temp is gained. causing more water loss and the result is airlock, with your fan not coming on and the car will def overheat.

Good luck Like i said i Used a Medium Sized Screw driver heated it over a candle and then Melted the screw driver into the Broken off Bit of the Screw.

Good Luck Buddy you need A LOT of Patience for this one. :thumbs:

 

[Dippies]

Any feedback

 

[Rooi_Willie]

:bravo::bravo::bravo:

 

[Philip Foglar]

Interesting read! And glad you got this sorted out!

Coincidentally I DIY changed the coolant on my E90 330i last night. This does of course have the electric water pump, but only has the bleed screw on the reservoir - same as the 320d I gather.

If you are draining the cooling system from the radiator drain plug, first of all be very very careful too since this tends to split or break very easily! It is advised to replace with a new plug which is cheap enough when changing the coolant. Then the other tip - it does not seal by the amount that it is tightened, but simply by the rubber O-ring, so all you need to do is tighten it lightly (as in really lightly). Also in both the removing and replacing of this plug, go slowly and gently and make sure you have a nice and wide flat screwdriver.

With the E90's with the N52 motor (I gather N54/5 too), add the premixed coolant into the reservoirs with the bleed screw opened (a few turns) until coolant minus bubbles begins to spill out from the bleed screw. Then close the bleed screw and reservoirs - you are now ready for the electric pump vent procedure which involves setting the climate control to the highest temperature on both sides and the fan to the lowest speed, then with the ignition on (and foot off the clutch or brake pedal) press the throttle down to the floor and hold for 10 seconds or until you hear the pump. The process takes roughly 10-15 minutes and it is recommended to run the vent procedure at least twice. After each vent procedure open the reservoirs to release any built up air pressure.

 

[JENICH]

Glad you sorted out dippies, very well put together description.

How is the software and DP treating you btw

 

[ngoako7]

Nice writeup,now upload them pics

 

[CliftonH]

Dippies I got respect for you man. I have no patience. I would be screaming and swearing and cursing for nothing. So when can u bleed my car. Lol. Okay seriously how often should you bleed the system and change the coolant. I'm scared to change it. Wonder how much bmw charges. I did notice a delay in fan coming on. But I guess the engine maybe not as hot as I thought. No engine warning light or anything. The fan works. So guess all good for now. But well done dippies I admire people who take care with they car. I was just saying last night that I just bought tools and going to start doing everything myself on the car now. These mechs are a waste of time and money. Dippies where u based.

 

[Dippies]

Glad you sorted out dippies, very well put together description.

How is the software and DP treating you btw

Software is really running like my other thread says I am in love with my car again, with no hassles and no fuss. I also think i got a Awesome power and Eco Gain like Rolf said Sporty Eco Tune, as i Requested. I will never look back. :thumbs: I can Truly recommend this to anyone.

Dippies I got respect for you man. I have no patience. I would be screaming and swearing and cursing for nothing. So when can u bleed my car. Lol. Okay seriously how often should you bleed the system and change the coolant. I'm scared to change it. Wonder how much bmw charges. I did notice a delay in fan coming on. But I guess the engine maybe not as hot as I thought. No engine warning light or anything. The fan works. So guess all good for now. But well done dippies I admire people who take care with they car. I was just saying last night that I just bought tools and going to start doing everything myself on the car now. These mechs are a waste of time and money. Dippies where u based.

Thanks man i Reside in Centurion You we welcome to come through and i will gladly assist you. We will just have to wait a While for the car to cool off Completely before we attempt it. so bring the Girl or Whife along and we can have a Braai while we wait. :rollsmile: :thumbs: