Coolant flushing

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dazthephot
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Coolant flushing

Post by dazthephot » Mon 29 May, 2017 10:21

Ok so it's time for a coolant flush and replace.
I want to use distilled water as the good book says but is that really necessary?

I guess if it is I'll have to flush with it too as I've been topping up with tap water over the years.




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BladeRunner919
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Re: Coolant flushing

Post by BladeRunner919 » Mon 29 May, 2017 12:34

Not necessary, but it's so cheap, why wouldn't you? :D

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dazthephot
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Re: Coolant flushing

Post by dazthephot » Mon 29 May, 2017 13:51

very true..

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dazthephot
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Re: Coolant flushing

Post by dazthephot » Mon 29 May, 2017 14:24

BladeRunner919 wrote:Not necessary, but it's so cheap, why wouldn't you? :D
I don't suppose you know the capacity do you?


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BladeRunner919
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Re: Coolant flushing

Post by BladeRunner919 » Mon 29 May, 2017 16:28

My M44 is about 5 liters all in - not sure what engine you have.

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dazthephot
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Re: Coolant flushing

Post by dazthephot » Mon 29 May, 2017 17:54

Sorry. 1.9 m43


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mrscalex
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Re: Coolant flushing

Post by mrscalex » Mon 29 May, 2017 21:14

When you drain the system via the radiator and block plug I believe a quantity of coolant remains in the heater matrix.

So if you flush with plain water you will leave a quantity of it in the system. And whether you flush with plain or distilled you'll need to remember to make a stronger mix of coolant to water to compensate.

I just flush out the radiator as that can drain fully. I'd rather have a bit of old coolant that gets mixed in than use plain water that could cause some distress to the internals. Particularly as we live in a very hard water area.
ImageImage
1999 Z3 1.9 Boston Green (Dimitri) - My brother's car owned from new and restored by me
2001 Z3 2.2 Topaz Blue (Trudy) - My car rebuilt from a write-off
2002 Z3 2.2 Titan Silver (Okus) - Project car waiting for a new engine
2001 Z3 2.2 Topaz Blue (Debra) - Donor car/breaker
1998 Z3 1.9 Boston Green (Allsworth) - Donor car/breaker now gone to Z3 heaven
Always happy to try and help with spares :)

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dazthephot
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Re: Coolant flushing

Post by dazthephot » Mon 29 May, 2017 22:51

Do you use normal anti freeze or the premixed bmw stuff?


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mrscalex
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Re: Coolant flushing

Post by mrscalex » Mon 29 May, 2017 23:01

BMW concentrate.

I'd happily use Halfords or quality alternative but the BMW stuff comes in around the same price.
ImageImage
1999 Z3 1.9 Boston Green (Dimitri) - My brother's car owned from new and restored by me
2001 Z3 2.2 Topaz Blue (Trudy) - My car rebuilt from a write-off
2002 Z3 2.2 Titan Silver (Okus) - Project car waiting for a new engine
2001 Z3 2.2 Topaz Blue (Debra) - Donor car/breaker
1998 Z3 1.9 Boston Green (Allsworth) - Donor car/breaker now gone to Z3 heaven
Always happy to try and help with spares :)

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dazthephot
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Re: Coolant flushing

Post by dazthephot » Mon 29 May, 2017 23:11

Oh right so it's not pre mixed it needs diluting with distilled water or have I got that wrong and you just pour it straight in?


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Del
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Re: Coolant flushing

Post by Del » Mon 29 May, 2017 23:21

The BMW stuff is strange blue, inky looking stuff which I haven't been able to duplicate elsewhere - it's longlife so I tend to stick with it. I get my distilled water from Tesco - just over £1 for 2.5 litres. I 50/50 mix it in a separate container (litre by litre) and pour it in.

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dazthephot
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Re: Coolant flushing

Post by dazthephot » Mon 29 May, 2017 23:43

Ah beauty thanks seems an easy way to go.


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Cooper01
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Re: Coolant flushing

Post by Cooper01 » Sun 04 Jun, 2017 08:25

I have been reading up a lot about this as I suspect my heater matrix is a bit clogged.

From my research I conclude:....

When you do the flush ensure that the heater is on the max setting to keep the matrix open fully.
drain the radiator and coolant from the block, if you have a screw in there for draining.
if the system if contaminated use a flush as per product procedure.
only use the bmw blue coolant. the dilution instructions are on the bottle.
use distilled water only. tap water contains contaminants which can foul the system and heater matrix [it gets HOT in there]
bleed the system, run the engine, check levels and top up as required.

Note:
The plastic plug in the radiator is likely to be very brittle so be prepared to get a replacement [they are expensive!] :head:
bmw recommends replacing the coolant every 4 years in the Z3 and 3 years in the ///M.

cheers.

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dazthephot
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Re: Coolant flushing

Post by dazthephot » Sun 04 Jun, 2017 18:11

Thank you for the advice. I bought 12 litres of deionised water from Tesco cos it was only a pound or so for 2.5l. I got 3l of bmw coolant for about £20 from a bmw geezer on fleabay. So I'm ready to go.
I'm guessing that you turn the heater dial to hot then put the ignition on and run the fan? Right ?


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dazthephot
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Re: Coolant flushing

Post by dazthephot » Sun 04 Jun, 2017 18:48

Also once you've filled it with deionised water for the initial flush would you run the engine a short while to circulate it?


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Cooper01
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Re: Coolant flushing

Post by Cooper01 » Mon 05 Jun, 2017 00:56

Hi. Watch YouTube videos particularly Otto from Bavarian Auto.

I am going to flush with an​ engine flush product in my coolant. Run with heater on highest setting no need for the fan to be on, then Drain. Then fill with tap water and run. Drain. Then run with distilled water, not any other type, and drain. Some water will remain but that's ok because it is distilled. Then calculate the amount of BMW coolant required and put all of that in. Fill with the water. Run, bleed, and top up with the water. Done. Always leave the heater on highest setting.

It might be excessive but I want the system to be really clean and functioning to is highest level.

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dazthephot
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Re: Coolant flushing

Post by dazthephot » Mon 05 Jun, 2017 08:10

Thanks for the tip.


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