mustard in my radiator?

[caprisecca]

so i changed my oil yesterday and thought i would check my water antifreeze level and seen this

so i dont know what this is from, it hasnt been over heating. everythings seems to be running perfectly normal except a rough cold idle. can anyone tell me what this is from. btw i flushed my radiator and block out like 6 times till it started coming out clear.

[DriverOne]

Flushing your radiator was the appropriate action, for sure. That looks like the same kind of rust that was in my wife's system, only hers had been left like that a while. That's an unusual color, for sure...

[caprisecca]

just thought i would mention. it was only about two months ago i swapped my old b3 for one outta a aspire, it only had 40k miles but it had been sitting a year or so. was this some minor rust forming inside the block? is there any solution or additive to clean it out better than just a water flush?

[Aaronbrook37]

Classic electrolysis. It happens when you top up your radiator with tap water rather than distilled water. If you've been running anything but pre-mixed antifreeze and distilled water, there's your answer. Definitely gonna want to flush that out two or three times minimum... use the strongest radiator flush kit you can find and be very thorough. Available at literally any auto parts stores. Don't forget to unclog your heater by putting the heat to max when you flush it.

[Spike]

I remember someone putting Dawn in the radiator/heater core to give them a real cleaning - BUT don't take my word for it, search it.

Don't wanna cause bubbles of soap in your engine.

[bravekozak]

Would CLR (Calcium Lime Rust) be too aggressive? It is essentially EDTA (Ethylene Diamine Tetraacetic Acid), a strong chelating agent. You would really have to make sure you ran a hose through your system after you had used it. I would try it on a little bit of the "mustard" to see what happens.

[navdoc101]

Cascade dish powder, If you can find it plain, no fragrence or other additive. Some members on here use it. Do a search.

[blkfordsedan]

Pardon me...........but would you have any Grey Poupon?

[sickfleming]

Huh. I was going to assume somebody mixed the orange and green coolant together. Some of the guys at AutoZone call it GM mud. lol
My last Festiva had that going on before I gave it an enema from hell lol