Changing coolant

[BIGRED]

With the engine cold I opened the drain on the radiator. To get to the plugs on the block, I had to remove sheet metal plates on the underside of the car. Also the bolts ARE 13mm NOT 19 as in Bentley's. Ran water through it till clear and then added blue at a 50/50 mix taking about 12 qts (M60) which seems a tad low. Ran it till warm with the rad cap off and once it circulated topped it off and closed it up. Also Bentley's talks about burping the system. At least on my M60, I see no such bolt. So it seems the Bentley manual is a guide rather than the rule.



Don

[Fetch]

the m60 is auto bleeding :)

[Spasso]

The V8 cars burp themselves automatically.
After driving the car around for a while and let it cool overnight. Check the level in your header tank when it is cold and top off accordingly.

Any pictures of your Touring? My dad has a '94 iT as well.

[e34musician]

I'm about to do the flush. If you flush with garden hose water, how do you know you drain them all out before adding the pre-mixed coolant?

I'm sure there are some tap water left in the system, will pre-mixed coolant + tap water be too weak? Anyone have done this the same way?

Thanks!

[Chris'91'525i]

I'm about to do the flush. If you flush with garden hose water, how do you know you drain them all out before adding the pre-mixed coolant?
I'm sure there are some tap water left in the system, will pre-mixed coolant + tap water be too weak? Anyone have done this the same way?
Thanks!

I've done it for years like this, and it works well ;

I flush the cooling system by first draining the radiator, then close the drain plug.
I then disconnected the upper radiator hose at the radiator and run the motor with the heater on 'full heat' setting, with blower going.
It takes me about 10-15 minutes to thouroughly flush the cooling system.
As you keep adding water from the garden hose to the radiator fill neck, the old coolant flushes out of the entire cooling system through the disconnected upper Rad. hose, (you will want to Rev. the engine every now and then, to get the old stuff to pump vigorously out of the cooling system). Don't worry it's not going to shoot out like a fire hose, not even close :) ....
You will also want to be continually standing by to add water as needed to the Rad. as it's pumping out of the upper Rad. hose, and the thermostat cycles between opening and closing. (Reving motor helps speed this up too).......
After everything is running clear with no traces of coolant or foamy water coming out of upper Rad. hose, I do a final flush with 3-4 gallons (more if you want) of distilled water to flush the garden/tap water out of the motor.
When that's done shut the motor down, and drain the Rad. of all water, then tighten Rad. drain plug and reconnect upper Rad. hose.
You will now have distilled water in the engine block, heater core etc.....
Find your cooling system capacity and add straight coolant to the Rad. equaling about half of that capacity.
Then use distilled water to top off system with motor running, to bring it up to Temp. so you can bleed it ,if needed.
I have a gallon of 50/50 mix to use for final topping off after a few heat and cooling cycles.

[e34musician]

Thanks for the info. I remembered seeing people flush this way when I was a kid (in the 70's -> 80's) in a warm / hot country that do not require anti-freeze. Only water is needed in the "old" car back then. And you have fill water directly into the radiator cap.

Seems like this is a very clean flush, but I may need an extra hose to avoid spliting the coolant all over the place from the upper hose.


I've done it for years like this, and it works well ;

I flush the cooling system by first draining the radiator, then close the drain plug.
I then disconnected the upper radiator hose at the radiator and run the motor with the heater on 'full heat' setting, with blower going.
It takes me about 10-15 minutes to thouroughly flush the cooling system.
As you keep adding water from the garden hose to the radiator fill neck, the old coolant flushes out of the entire cooling system through the disconnected upper Rad. hose, (you will want to Rev. the engine every now and then, to get the old stuff to pump vigorously out of the cooling system). Don't worry it's not going to shoot out like a fire hose, not even close :) ....
You will also want to be continually standing by to add water as needed to the Rad. as it's pumping out of the upper Rad. hose, and the thermostat cycles between opening and closing. (Reving motor helps speed this up too).......
After everything is running clear with no traces of coolant or foamy water coming out of upper Rad. hose, I do a final flush with 3-4 gallons (more if you want) of distilled water to flush the garden/tap water out of the motor.
When that's done shut the motor down, and drain the Rad. of all water, then tighten Rad. drain plug and reconnect upper Rad. hose.
You will now have distilled water in the engine block, heater core etc.....
Find your cooling system capacity and add straight coolant to the Rad. equaling about half of that capacity.
Then use distilled water to top off system with motor running, to bring it up to Temp. so you can bleed it ,if needed.
I have a gallon of 50/50 mix to use for final topping off after a few heat and cooling cycles.

[BIGRED]

The V8 cars burp themselves automatically.
After driving the car around for a while and let it cool overnight. Check the level in your header tank when it is cold and top off accordingly.

Any pictures of your Touring? My dad has a '94 iT as well.

Not as yet....White on Natural