Cooling System Rust

[BRADESTAR]

I replaced my thermostat a while back (within a year). Flushed and filled the system then. The coolant that came out was orange and had some flakes of rust in it.

Now I am attempting to replace the entire cooling system components. Upon draining the coolant it too had turned orange/brown. No chunks this time. I'm worried about this continuing problem causing issues.

It is stripped down now. Currently, I am planning on getting it all back together and flushing it with Vinegar/H2o a few times, but wondered if there is something that I can do now to rinse out the block (I assume that is the source) while I have the water pump and plastic bits out.

Thanks in advance for any advice...am I'm concerned about nothing here?

[BlackBMWs]

I replaced my thermostat a while back (within a year). Flushed and filled the system then. The coolant that came out was orange and had some flakes of rust in it.



Now I am attempting to replace the entire cooling system components. Upon draining the coolant it too had turned orange/brown. No chunks this time. I'm worried about this continuing problem causing issues.



It is stripped down now. Currently, I am planning on getting it all back together and flushing it with Vinegar/H2o a few times, but wondered if there is something that I can do now to rinse out the block (I assume that is the source) while I have the water pump and plastic bits out.



Thanks in advance for any advice...am I'm concerned about nothing here?



I've not back flushed mine, as I've not had that issue on the 3s or 5s I've had. Do refill it tho with 50/50 mix of BMW coolant and distilled water. I did notice on my wifes M42, a build up of coolant residue in the cooling sytem, I'll see better when I renew the Thermostat and Water Pump. I will renew it with a 50/50 BMW coolant mix as I believe it has better properties for the Aluminum heads we run. I run it also in my M62tu which is also an aluminum block in addition to the heads.



Ring me if you have any questions. :cool:

[BRADESTAR]

It seems like the bolt in the passenger side block is the lowest point in the system. The picture should show some water sitting in there. That was because the plug there in the back was blocked by small flakes. It happened twice as I'd add the distilled water/vinegar through the pump spot and plastic bits. Seems to flow pretty clean now.

Now that I'm satisfied that most chunks seem cleared. I'm debating doing the vinegar cycle at all. I've also found sources that say "Water Wetter" helps with rust so I'll put that in with the final coolant mix.

Still accepting suggestions. I have a feeling my coolant may just be rust colored from now on.

http://i944.photobucket.com/albums/ad286/BRADESTAR/IMG_20150303_182400_zpspyqdu7sp.jpg (http://s944.photobucket.com/user/BRADESTAR/media/IMG_20150303_182400_zpspyqdu7sp.jpg.html)

[jca]

Definitely use BMW coolant and distilled water...John