• Don't mix coolant types/colors
• Replace it every 3-4(max) years

Or this will happen

That's a surprise.
When the later stuff was introduced, the warning was that if it was mixed, the change interval would just reduce to that of the earlier stuff, otherwise no harm.
Are you sure there's not another problem, like oil mixing with the coolant across the head gasket?
Gonna need a good flush.

Looks like rad weld in it too

Weird indeed hmm

This is 6 years old coolant mixed with a blue color one and used for 2 more years.

Also there was a big leak from thermostat and a lot of corrosion around plastic fittings and hose.

Replaced both thermostat and pump anyway.

I flushed the system completely now it's clean.

The weird thing is that there was this kind of red mud all over expansion tank. You can see it's on top of the tank too like a thin film.

Oil is clean, no coolant loss since the repair (6000miles) coolant is still clean too.

Maybe it was contaminated from long exposure to air from the leak?

Ckem247 said:

Looks like rad weld in it too

Click to expand...

I thought that too but rad was clean actually. (I checked the water I used to flush it)

Was this off your car? If it was glad it's sorted for your own sake

Yup. I'm about to change the oil and I remembered these pictures.

Yeah think I might flush mine in the next week or too aswell as brake fluid

Hey, how did you go about cleaning up the coolant tank? Mine's having some black/brown dots and dirt in it. But all clothe, wire brushes and rice that I threw in to wash only managed to clean up the middle portion of the tank.

the two sides of the tank seems to be isolated and only have a 4mm opening for coolant to pass thru...

Terenc3Le3 said:

Hey, how did you go about cleaning up the coolant tank? Mine's having some black/brown dots and dirt in it. But all clothe, wire brushes and rice that I threw in to wash only managed to clean up the middle portion of the tank.

the two sides of the tank seems to be isolated and only have a 4mm opening for coolant to pass thru...

Click to expand...

Yes that's true, tank is divided into isolated parts.

I tried to clean it with just soap and boiling water, helped a lot but still left some.

After all that time with the new coolant the tank is still very clean!

Is yours in the same condition as mine?

Well mine wasn't that bad. It was starting to sludge up (left of attached picture) which I believe it was due to my thermo housing plastic nozzle breaking and the workshop topped up coolant of different kind after the fix.6

I did a super flush (four times distilled water flush) and cleaned the coolant tank. Using some rice grains and very very vigorous shakes seemed to remove most of the sludge but some dark dots and brown lines still remains. Hopefully they will be gone eventually.

Picture attached.

Sidenote: I replaced the OEM hose clips with worm type as I cannot find the OEM ones anymore after they broke when I was trying to remove the tank!

cmosfxx said:

Yes that's true, tank is divided into isolated parts.

I tried to clean it with just soap and boiling water, helped a lot but still left some.

After all that time with the new coolant the tank is still very clean!

Is yours in the same condition as mine?

Click to expand...