Green Build Up in Coolant

[colorado.dmax]

Inspecting under the hood the other day I noticed what looked like algae on the inside of the coolant tank. Took off the cap and found this green residue. Anybody know what could be causing this? I know if you mix green coolant and dex you get a brown sludge. But I know 100% that dex has only ever been put in.

 

[colorado.dmax]

Bump

 

[ty_LBZ]

Mix green antifreeze with Dexcool??

 

[OregonDMAX]

Mix green antifreeze with Dexcool??

Read his original post...


OP what kind of water have you used when flushing the system... Maybe your water is the cause? Just a thought.

 

[Dozerboy]

Algae growing in the water that is condensating inside the tank maybe. Is it only above the coolant level?


Sent from my iPhone digging a ditch near you.

 

[colorado.dmax]

Only water that I've used is 100% distilled. And I only use straight dexcool and mix it, never the premixed (not that it should matter).

It does appear to only be above the coolant level in the tank. I don't know that it could be algae though?? No sunshine under the hood, and you'd think with the temperatures and chemicals in the dex nothing would grow? It's not as dark as algae typically is around here and it's not slimy/slippery...

 

[OregonDMAX]

I guess the next question is when was the last flush, what did it look lime then and what does it look like now.

 

[chandler583]

I would do a flush just to verify that it isn't inside the radiator.

 

[DAVe3283]

I'd pull the coolant bottle off, drain rest of the coolant (in that order), and look inside the thermostat housing to see what, if any, crap is in the motor.

If the motor looks good, flush the system a few times with distilled water, and throw a new coolant bottle and cap on.

Bottle is $60 on Amazon, cap is cheap from a local store.

It really does look like algae, but that doesn't make sense.

 

[colorado.dmax]

This is the weird part though, the coolant looks fine...you unscrew the cap and ignore the green sludge on the cap and walls of the tank and look at the fluid and it looks like regular orange dexcool.

 

[Woodster]

Looks like Cafe Rio creamy tomatillo sauce.

Got any "friends" that may have pulled a prank?

 

[Dozerboy]

Could be grease maybe oil I guess. Not sure how it would of got in there, but grease can look like that when mixed with water.