93 explorer rust orange coolant

[gooter87]

I did a head job about 5 months ago, i had a leak between cylinder 5 and 6. got that taken care of and had to flush the radiator for that... Now i went to add a t-stat since i left it out after the head job.. when i pulled off the pipe that houses the t-stat.. the water that came out was orange.. like rust.. i put coolant in it when i changed it and it was green and clean.. now its rust orange.. what would cause this? After all the work i did.. i would hate to ruin the motor due to noneducational knowledge about the cooling system.. any information would help... Also the temp gauge rises up to about 3/4 way to hot then drops right back down after i turn or if i am at a light as soon as i drive.. thoughts???

 

[Jason94sport]

Iron blocks rust. It is a 1993. Mine is a little orange too. Not much you can do other then flush it more often.

 

[JohnnyO]

Flush it again and keep an eye on it. Might have had rust laying around in there from before. Flush it with distilled water too. Tap water can be crap. Depending where you live there can be a mess of iron and other metals in your water. It's worth dropping $4 on 4 gallons of distilled water. Fill it, run it (I drive a loop around town), drain it, repeat until the water comes out pretty clean. Then fill it 50% of capacity with antifreeze and top it off with a little of each until it's full.

FWIW I don't bother with the radiator petcock to drain it, I just pull off the bottom hose. Much faster that way.

 

[DirtJunky]

You can flush it all you want but if you had water in there to long then you'll need a new radiator. It can be rust or means your coolent is boiling and getting to hot. The inside of your radiator could be completely covered in rust and if it is then you'll always have that brown till you replace it

 

[Anime]

Rust happens when the coolant is left in too long, and loses its ability to inhibit rust and corrosion.

Best bet is to drain it, and either flush the system with a hose, or fill it with water, run it, and drain a few times to clean as much rust out as possible (be sure to follow the burp procedue each time you refill to keep any air out), then refill with new coolant/water in a proper 50/50 mix.

Flushing with a hose is the way to go if it's really brown. It won't be perfect and tap water isn't the best thing to use in a cooling system, but flushing until the water runs clear will go a long way to cleaning the system. Once it's clean, you may want to use a new thermostat (rust can clog a thermostat), and use distilled water to flush and refill after that.

 

[gooter87]

Sorry for the late reply.. had a nicely rusted heater core.. and my cycling temp was due to all the leaking of the coolant through the corroded core. Nice $25 fix and 4 bolts... ford had a great design with the clam shell drain tube out of the exploder and not inside on the floor she is happy and running great! Thanks for all the input!!!