Coolant Issue

As I was driving coolant sprayed up the passenger side windshield, the temperature gauge went to the red and the car started beeping. I pulled in and found out the expansion tank had a leak. The car was towed to a garage and they diagnosed the expansion tank seal as broken and replaced the expansion tank. They then filled up the tank and gave the car back to me. I then found the fan in the car to come on really loud, the temperature gauge go up and the air to only come out as cold. I also noticed the coolant to be bubbling and steaming out of the cap under the bonnet. The mechanic then had the car for 5 days as he did a series of bleeds, convinced that the issue is air pockets. Each time he's called me to say it's sorted, its not been. He's done checks on the water pump and thermostat as well as a block test to check for a failing head gasket and all are fine.
I've now told him to do a vacuum fill of coolant to remove air pockets. Any advice would be greatly appreciated. As far as i'm aware he's tested for other issues, leaks etc. All is fine. He's then bled it with the front lifted, back lifted and still having this issue of coolant bubbling, air flow cold, temperature gauge rising slightly and fan really loud.
Thanks
 
AbrahamSaul said:
As I was driving coolant sprayed up the passenger side windshield, the temperature gauge went to the red and the car started beeping. I pulled in and found out the expansion tank had a leak. The car was towed to a garage and they diagnosed the expansion tank seal as broken and replaced the expansion tank. They then filled up the tank and gave the car back to me. I then found the fan in the car to come on really loud, the temperature gauge go up and the air to only come out as cold. I also noticed the coolant to be bubbling and steaming out of the cap under the bonnet. The mechanic then had the car for 5 days as he did a series of bleeds, convinced that the issue is air pockets. Each time he's called me to say it's sorted, its not been. He's done checks on the water pump and thermostat as well as a block test to check for a failing head gasket and all are fine.
I've now told him to do a vacuum fill of coolant to remove air pockets. Any advice would be greatly appreciated. As far as i'm aware he's tested for other issues, leaks etc. All is fine. He's then bled it with the front lifted, back lifted and still having this issue of coolant bubbling, air flow cold, temperature gauge rising slightly and fan really loud.
Thanks
You don't say which engine.
 
E85 2006 2.5i. I drove it for about 5mins at 20mph to where I could pull in safely. When the initial problem happened the engine temperature went to the far right red then i slowed down and it went back to the middle as I pulled into the car park.
 
Did this garage know they had to do the proper bleed procedure to activate the electric water pump?

And to have the heater controls set fully hot so air can get out of the heater matrix
 
Scooba_Steve said:
Did this garage know they had to do the proper bleed procedure to activate the electric water pump?

I’m not sure but now thinking presumably not, are you able to explain the proper bleed procedure please? Thanks
 
AbrahamSaul said:
Scooba_Steve said:
Did this garage know they had to do the proper bleed procedure to activate the electric water pump?

I’m not sure but now thinking presumably not, are you able to explain the proper bleed procedure please? Thanks
Just to confirm…….. 2006 facelift?? N52?
 
From NewTIS

Do not open the sealing cap of the coolant expansion tank during the bleeding procedure.

Switch on the low-beam headlights to perform the bleeding procedure. If the low-beam headlights are not switched on, the ignition (Terminal 15) will switch off automatically after a certain period of time and interrupt the bleeding procedure.

Connect battery charger.
Switch the ignition on.
Switch on low-beam headlight.
Set heating to maximum temperature. Set fan speed to lowest setting
Press accelerator pedal for 10 seconds to floor. Engine must not be started.
The bleeding procedure was started by pressing the accelerator pedal and takes approx. 12 min. (the electrical coolant pump was activated and switches off automatically after approx. 12 min).
Then adjust filling level in coolant expansion tank to maximum.
Check cooling system for leaks.
If the cooling system bleeding has to be performed again, deactivate DME completely (remove ignition key for approx. 3 minutes). Then repeat procedure.
 
Thank you for the detailed reply I’ll have a look now as to whether its the n52 or m54 The mechanic did mention some bmws having electrical bleeding system but indicated that this one didnt :/
 
AbrahamSaul said:
Thank you for the detailed reply I’ll have a look now as to whether its the n52 or m54 The mechanic did mention some bmws having electrical bleeding system but indicated that this one didnt :/
Simple check. Does it have a dipstick (M54)
Or what sort of front fog lights? Round is prefacelift (M54), long thin ones (usually full of condensation) is facelift (N52)
 
AbrahamSaul said:
It has a dipstick in the coolant but not the oil. Does that help determine, sorry for my lack of knowledge
Oh yes, sorry, I meant the oil.
So no dipstick means N52 and therefore the procedure I outlined should be followed.
 
AbrahamSaul said:
Thank you for the detailed reply I’ll have a look now as to whether its the n52 or m54 The mechanic did mention some bmws having electrical bleeding system but indicated that this one didnt :/
Sounds like he's an idiot then.

Grab a battery charger and bleed it yourself :thumbsup:
 
enuff_zed said:
From NewTIS

Do not open the sealing cap of the coolant expansion tank during the bleeding procedure.

There's a section before that for my VIN:

TIS said:
Only when venting!

Open cap (1) on coolant expansion tank.

Open vent screw (2).

Important!
Fill coolant expansion tank up to lower edge of filler neck with recommended coolant.

Pour in coolant slowly.

Close vent screw (2) when bubble-free coolant emerges

Close cap on expansion tank.
 
I've not needed a vac filler for the Z4 due to the elec pump. But I did get this one for other engines and it works *very* well (you do need a compressor or air line though).

https://www.drapertools.com/product/09544/universal-cooling-system-vacuum-purge-and-refill-kit/
 
Scooba_Steve said:
enuff_zed said:
From NewTIS

Do not open the sealing cap of the coolant expansion tank during the bleeding procedure.

There's a section before that for my VIN:

TIS said:
Only when venting!

Open cap (1) on coolant expansion tank.

Open vent screw (2).

Important!
Fill coolant expansion tank up to lower edge of filler neck with recommended coolant.

Pour in coolant slowly.

Close vent screw (2) when bubble-free coolant emerges

Close cap on expansion tank.
Yup that's correct. That bit didn't pop up in my search for some reason.
You'd think even the mechanic would at the very least got that bit sorted though...................... wouldn't you? :roll:
 
AbrahamSaul said:
Thank you all for your help.
I have the VIN here with me is there anyway way to check using this whether its M54 or N52?
Sure, you can PM it to me (only need the last 7 digits).
 
enuff_zed said:
You'd think even the mechanic would at the very least got that bit sorted though...................... wouldn't you?

Frankly, no :lol:

Shoddy 'professionals' are why I do everything I am able to myself.
 
Thanks everyone for the help. Confirmed its N52 and will head down to the garage tomorrow and go through the process with the mechanic.
 
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