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Coolant rust?

joney

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Just checked my coolant reservoir, it's a orange/brown color. Can rust get into the coolant? I believe mine should have the green coolant, not sure if the orange had been used by the previous owner or if rust got into it! Going to take it in soon for flush and coolant replacement, but is rust a thing with these? 98 XLT SOHC 4.0
 



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C420sailor

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Yep, this happens when you don’t regularly change the coolant and flush the system. Antifreeze has corrosion inhibitors in it, but they don’t last forever.

Drain everything, flush the system with a hose. Leave enough room to add a quality flush chemical, if that’s your thing. Follow the directions. Drain it all out, flush again, fill with 50/50.

It’ll look even worse if green and orange have been mixed over the years.
 






J_C

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Probably most likely that the last coolant change used gold or orange coolant, then add a little corrosion on top of that.
 






Pinout

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Just checked my coolant reservoir, it's a orange/brown color. Can rust get into the coolant? I believe mine should have the green coolant, not sure if the orange had been used by the previous owner or if rust got into it! Going to take it in soon for flush and coolant replacement, but is rust a thing with these? 98 XLT SOHC 4.0
 






donalds

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Flush -n-done
 






Pinout

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The block is cast iron, and the heads are cast aluminum. Cast iron is very strong, but it does rust if the coolant gets too diluted or old. A flush will get the old coolant out and new coolant in. If you want to get the rust out safely, try "evapo-rust". You have to run it with plain water and evapo-rust for several days, so don't do it in the winter if the water could freeze.
 






BrooklynBay

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KeenKilo

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My thermostat housing was severally rusted
 






C420sailor

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Flushed my mom’s Expedition today. You wanna talk rust…flakes of it came out.

I did this job about 10,000 ago, but her heater core plugged up, so I’m doing it again. Much better this time, but still kinda nasty. This is what happens when you don’t stay on top of your maintenance!
 






joney

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Thanks everyone for the info. Going to take it in for the flush, and the green coolant. Not doing it myself as it's frozen and snowy here. Planned maintenance got pushed back due to unexpected repairs taking so long! Got my hood struts in the other day - and also found a melted, loose spark plug boot! Still have to get the windshield washers squirting yet. Was glad to see the 4wd works nice, in the foot of snow we got last week. Still finding out more about my Ex, and the previous owner's good/bad maintenance!
 






donalds

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My wife and I went through all these repairs and upkeep
Its a pain at first
Soon you will have a nice reliable truck
Keep at it
 






CDW6212R

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Probably most likely that the last coolant change used gold or orange coolant, then add a little corrosion on top of that.

Ditto, likely someone put the orange antifreeze in it, and it's been left too long, old and some corrosion. I use either coolant, they all generally can be mixed, the key is keep it all fresh. Right now Walmart is the best source for the low cost pure coolant, Prestone gallon for $11. That coolant is yellow, and BTW BMW has one that's blue. I like that idea too, I bought three gallons of that when it was on sale a couple years back, about $20 I think they were per gallon.
 






donalds

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Walmart is the best source for the low cost pure coolant, Prestone gallon for $11. That coolant is yellow, and BTW BMW has one that's blue. I like that idea too, I bought three gallons of that when it was on sale a couple years back, about $20 I think they were per gallon.
I run the yellow prestone
Been great so far
 






GlennS195378

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Thanks everyone for the info. Going to take it in for the flush, and the green coolant. Not doing it myself as it's frozen and snowy here. Planned maintenance got pushed back due to unexpected repairs taking so long! Got my hood struts in the other day - and also found a melted, loose spark plug boot! Still have to get the windshield washers squirting yet. Was glad to see the 4wd works nice, in the foot of snow we got last week. Still finding out more about my Ex, and the previous owner's good/bad maintenance!
Don't focus on which color coolant to put in. There are many different colors on the market today and colors really don't mean much anymore. Just get one put in that is either spec'd for your vehicle (what the dealer will put in) or get a universal coolant (what you will get from most automotive shops). Most specify a 50/50 coolant/water mix for the best performance and temperature protection.

Since it appears there might be rust in your coolant, make sure you get a complete coolant system flush, not just a drain. And you might as well replace the thermostat at the same time...cheap insurance.
 






davidmmm69

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Just checked my coolant reservoir, it's a orange/brown color. Can rust get into the coolant? I believe mine should have the green coolant, not sure if the orange had been used by the previous owner or if rust got into it! Going to take it in soon for flush and coolant replacement, but is rust a thing with these? 98 XLT SOHC 4.0
Just never mix these Dexcool with Ethylene Glycol
 






davidmmm69

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Just checked my coolant reservoir, it's a orange/brown color. Can rust get into the coolant? I believe mine should have the green coolant, not sure if the orange had been used by the previous owner or if rust got into it! Going to take it in soon for flush and coolant replacement, but is rust a thing with these? 98 XLT SOHC 4.0
Just don't use these together Dexcool with Ethylene Glycol
 






Islandguyhere

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Good suggestions above tho if you see that much rust already it's too late for radiator. Youre going to have to replace it sooner then later now so might as well do it now or you'll be going thru all this again soon. Since you're going to spend all this money on flushing and such get a new radiator online shipped for around $75. Any wrench can put it in hour or less. GL
 






DMichaels

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And only use the tap water to flush, don't leave it in the system. Distilled water is the only water that should ever be allowed to stay.
 









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