You can do a complete flush using some Cascade dish detergent powder: Engine coolant flush
Does Dexcool do this?
Step one in putting in my new all aluminium radiator is obviously removing the current rad, hence removing all lines. Upon removing the heater core return line I saw the following. You can see the radiator line has had to be cut due to the seized nut. Ignore that. My question is about the dex-cool residue. I've seen this also in my expansion tank. It looks as though everything has been internally coated in brown paint. I'm thinking that the guts of the radiator, all my hoses and even the water passages of the block look similar(?). It may not look like it but I've been running with green coolant for about 20k miles with plenty of overheating cycles (i.e. lot's of opportunities for this stuff to get cleaned off and mixed with the green). Questions:
1) Is this normal for dex-cool or does this mean it was left sitting for an extended period?
2) Would a coating of this inside my radiator inhibit heat transfer?
3) How can I get all of this residue out of my coolant passages?
:
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1) Is this normal for dex-cool or does this mean it was left sitting for an extended period?
2) Would a coating of this inside my radiator inhibit heat transfer?
3) How can I get all of this residue out of my coolant passages?
:
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6.5L TD Cooling System Flush Videos
I flushed out my cooling system yesterday, took some videos and posted them on YouTube:
www.dieselplace.com
Thanks. I also think it's the clay tablets. If it's through the block I don't think that stuff is ever coming out. If it stays where it is and doesn't inhibit heat transfer I'll just carry on.
I back flushed the heater core and saw this (bear in mind I've been running green coolant for a considerable amount of time). I don't quite know what to make of it:
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I back flushed the heater core and saw this (bear in mind I've been running green coolant for a considerable amount of time). I don't quite know what to make of it:
By way of an update ...
I installed my new radiator after flushing everything the best I could. I have then filled and flushed after driving a couple of times. The fluid draining from the radiator looks as I expected - clearish with green tinge. After the last drain I removed the surge tank that heavily coated in brown stuff (probably clay residue) in order to put a new one in its place. I was quite surprised when the removed surge tank puked a load of very brown gunk all over my jeans. I managed to capture some and take a photo to contrast it to the fluid that came from the radiator drain. Important to note in the attached photo that the radiator fluid in the drain pan is discoloured due to other various auto slime that was already in there. It was actually clear with a green tinge.
I'm puzzled as to how the gross gunk in both the heater core lines and the surge tank has not managed to mix with the bulk of the radiator fluid with all of the draining, filling and driving that I've been doing? Is it possible that my water pump is not working effectively?
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I installed my new radiator after flushing everything the best I could. I have then filled and flushed after driving a couple of times. The fluid draining from the radiator looks as I expected - clearish with green tinge. After the last drain I removed the surge tank that heavily coated in brown stuff (probably clay residue) in order to put a new one in its place. I was quite surprised when the removed surge tank puked a load of very brown gunk all over my jeans. I managed to capture some and take a photo to contrast it to the fluid that came from the radiator drain. Important to note in the attached photo that the radiator fluid in the drain pan is discoloured due to other various auto slime that was already in there. It was actually clear with a green tinge.
I'm puzzled as to how the gross gunk in both the heater core lines and the surge tank has not managed to mix with the bulk of the radiator fluid with all of the draining, filling and driving that I've been doing? Is it possible that my water pump is not working effectively?
That brown does look like what dexcool can do when there's air getting into the cooling system.
I read extensively on the issues years ago. What I walked away with was that Dexcool is just fine so long as the system is sound and you don't mix in other coolants. If not and if left long enough it will go brown and then brown sludge, mostly from air mixing in.
Could be indicating there was an issue with your system and the dexcool that never completely came out is "letting you know".
My dexcooled LBZ is red and very liquidy and I always check it to make sure it stays that way. I've never mixed in anything else. When I flush I only ever get bits of paint and sand.
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