Thermostat brown.

[revmaster]

Pulled off a thermostat . Was fairly new one. New Celsius coolant antifreeze made by Prestone. Thermostat is brown.

 

[toolmanmike]

Looks like rust but a little mucky. . Did you flush the system before the new antifreeze?

 

[R413]

That's rust.
Use this to remove it. Amazing what it will clean up.

THERMOCURE Cooling System Rust Remover & Flush | CRC

 

[WileE]

Looks like rust but a little mucky. . Did you flush the system before the new antifreeze?

Mucky rust.

 

[revmaster]

Looks like rust but a little mucky. . Did you flush the system before the new antifreeze?

No. I was going to flush it. I took the water pump off . It's clean in the housing. I was checking the water pump .I'll reverse flush it. Using Celsius antifreeze. It's cheaper they say all garages use it. Antifreeze was a bit dirty but not bad. Looks clean coming out until it's in a pail then you see the dirt. . But color seemed ok..

 

[revmaster]

Mucky rust.

Looks like rust but a little mucky. . Did you flush the system before the new antifreeze?

No I just drained it. I will flush it in reverse. Plugging the thermostat and then flush through the heater hoses? Wonder how much that takes out ..

...

 

[toolmanmike]

That color of muck can also come from oil in the coolant. Double check those dipsticks for any foreign residue. I don't know what kind of antifreeze you used but in an old car that has had Ethelene glycol in it all it's life, that's what I would use. (the old green stuff)

 

[PurpleBeeper]

No. I was going to flush it. I took the water pump off . It's clean in the housing. I was checking the water pump .I'll reverse flush it. Using Celsius antifreeze. It's cheaper they say all garages use it. Antifreeze was a bit dirty but not bad. Looks clean coming out until it's in a pail then you see the dirt. . But color seemed ok..

1. Celsius antifreeze is based on ethylene glycol (good)
2. Celsius is an “OAT” (organic acid technology) antifreeze similar to dexcool. I recommend that antifreeze.
3. Originally Mopars used an inorganic acid based antifreeze with silicates. There is a hard-to-find Peak antifreeze with a green label that is close to the original antifreeze…BUT, I recommend you use what you have.
4. That is 100% for sure rust. I suggest an acid-based flush (basic auto parts store radiator flush) with distilled water, drain and fill with more distilled water, drain and add 50/50 Celsius
5. Color means NOTHING…..unless it’s muddy brown, which means rust….but really, antifreeze color means zilch, nada, zip