flushing the coolant system

[kwamek]

i just bought Prestone flush 'n fill kit to flush the coolant systems but im not sure which hoses to connect the back flow preventer coupler. anybobdy done this before please advise. thanks

[Qube]

Though I can't help you... be prepared for the flak of refilling with Prestone green! :(

[Chris'91'525i]

i just bought Prestone flush 'n fill kit to flush the coolant systems but im not sure which hoses to connect the back flow preventer coupler. anybobdy done this before please advise. thanks

I don't think those kits are recommended for cars with auxillary water pumps. (no idea what car you have. since it's not listed).

I just flushed my 525i by draining the radiator, and with the drain left open.I then disconnected the upper radiator hose, at the radiator. I then ran the motor with the heater on 'full heat' setting. As you keep adding water from the garden hose to the expansion tank, the old coolant flushes from the cooling system through the disconnected upper Rad. hose.
After everything was running clear with no traces of foam. I did a final flush with 4 gallons of distilled water. ( Our Albertsons is closing too. I got 4, 2 gallon jugs of distilled water for $2.50 :) ) .. I then let some more water run out of upper Rad. hose. Turn off motor, Let Rad drain/ Close drain fitting, connect upper hose and added 5 Qt. of BMW blue, and top off with distilled H2O.
Get the system to operating Temp. Bleed cooling system....Done
I did'nt even have add coolant mix after test drive, and system cooled......

[joshua43214]

If the system has not been abused, all yo need to do is drainthe engine and the radiator and refill it. otherwise, unplug all the hoses and flush in every direction with a garden hose until it runs clear.

[Blitzkrieg Bob]

works the best, just disconect the radiator and flush away!

Run the heater to clear the core.

Fill witn BMW blue and the world is in harmony.

[kwamek]

bmw 1992 525i model
thanks a lot for the help. :)




I don't think those kits are recommended for cars with auxillary water pumps. (no idea what car you have. since it's not listed).

I just flushed my 525i by draining the radiator, and with the drain left open.I then disconnected the upper radiator hose, at the radiator. I then ran the motor with the heater on 'full heat' setting. As you keep adding water from the garden hose to the expansion tank, the old coolant flushes from the cooling system through the disconnected upper Rad. hose.
After everything was running clear with no traces of foam. I did a final flush with 4 gallons of distilled water. ( Our Albertsons is closing too. I got 4, 2 gallon jugs of distilled water for $2.50 :) ) .. I then let some more water run out of upper Rad. hose. Turn off motor, Let Rad drain/ Close drain fitting, connect upper hose and added 5 Qt. of BMW blue, and top off with distilled H2O.
Get the system to operating Temp. Bleed cooling system....Done
I did'nt even have add coolant mix after test drive, and system cooled......

[winfred]

the block drain is a 19mm bolt by the exhaust manifolds, it's about at the 4th cylinder. green coolent won't hurt anything imho but as with any coolent it should be changed about every two years for maximum corrosion protection, for the record i see just as much crumbling plastic with the blue coolent verses the green if not more, i don't like how the blue coolent changes the color of everything


bmw 1992 525i model
thanks a lot for the help. :)

[Chris'91'525i]

Quote:
Originally Posted by Chris'91'525i
******************************
I don't think those kits are recommended for cars with auxillary water pumps. (no idea what car you have. since it's not listed).

I just flushed my 525i by draining the radiator, and with the drain left open.I then disconnected the upper radiator hose, at the radiator. I then ran the motor with the heater on 'full heat' setting. As you keep adding water from the garden hose to the expansion tank, the old coolant flushes from the cooling system through the disconnected upper Rad. hose.
After everything was running clear with no traces of foam. I did a final flush with 4 gallons of distilled water. ( Our Albertsons is closing too. I got 4, 2 gallon jugs of distilled water for $2.50 ) .. I then let some more water run out of upper Rad. hose. Turn off motor, Let Rad drain/ Close drain fitting, connect upper hose and added 5 Qt. of BMW blue, and top off with distilled H2O.
Get the system to operating Temp. Bleed cooling system....Done
I did'nt even have add coolant mix after test drive, and system cooled......


bmw 1992 525i model
thanks a lot for the help. :)

No problem,
I've used this method for many years, on all types of vehicles.
Takes about a half hour, but does a very thourough job.

I found when doing the final bleeding of this system, once it gets up to operating Temp. and system is nearly full.
I held the engine revs at a pretty high (2-3K). I then completely filled expansion tank to the very top, and quickly screw the radiator cap on.(put it back to idle after cap is back on).......
Then I bleed the air out.
After a test drive and it cooled completely, the coolant level was right at the cold fill mark on expansion tank.

Note: correct me if I'm wrong. But not sure if you should keep the Revs up while doing this with an automatic tranny. Thought I read you can't Rev stationary BMW's with auto trans.....

[mastermind]

i want to try a coolant flush myself...but where is the drain fitting for the rad...is it under the rad? i have no clue whatsoever so a good description would be great.

thanks.

[632 Regal]

bottom inside of the rad under the splash shield.

i want to try a coolant flush myself...but where is the drain fitting for the rad...is it under the rad? i have no clue whatsoever so a good description would be great.

thanks.

[kwamek]

the drain is the bottom of the radiator as indicated in the attached pic with instructions. You can unscrew the drain plug with your hand.





i want to try a coolant flush myself...but where is the drain fitting for the rad...is it under the rad? i have no clue whatsoever so a good description would be great.

thanks.

[kwamek]

bottom inside of the rad under the splash shield.

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