Crunch

I changed my sons whole cooling system out about 2 months ago. WP, T-stat, all hoses, rad cap, and radiator. Did a flush first because it was all orange and looked like a watery baby crap, super nasty. Changed everything out. Runs just below 210* even on 90+* days... Just checked it today, and the coolant is blackish, not green. No thickening or goopy look to make me think it is oil. Still running at the same temps no issues yet.
Does have some black gritty sandy stuff on the bottom of the rad cap.
Anyone ever seen this? Is it just from all the new hoses? Or maybe some of the junk was still in there and just reacted with the new coolant and the distilled water?
No issues with oil or trans fluid, so I'm not leaking anywhere that I can tell? WTH?

whowey

Two ideas come to mind.

One it is still crap out of the block and cooling system. With rusty nasty coolant, that means that the corrosion protection had broken down. That could be residue of that mess.

Also someone could have dumped stop-leak into it one time, and you are seeing some of that coming out.

00XJ49

If the coolant before was really old, it could have just been crap that got knocked loose from the flush. Drain and re-fill, see if it comes back.

trailsend.lake

i have seen some additives turn the coolant black, like stop leak, rislone, alumaseal,prestone to name a few. it could still be in your block.powerflush, drain and fill again, it should take care of it

theangler

I'm with these guys, if you're not overheating, it sounds like just crud in the system... Keep cycling coolant through (or just water for now if it's not too cold out)

Crunch

Was hoping that was all it was.. I'll try another flush and report back. Thanks guys.

trans_am7935

what i did is drain the whole thing then fill it up with only water. get it up to operating temp with the radiator cap off and then open the drain on the radiator. have a water hose handy and start to refill it up with warm water from a sink or something. keep filling it up to keep the water in the radiator full and do this until all the water being drained out the radiator is clear. then turn the car off and drain the rest. take one gallon of concentrate radiator fluid and pour it in there. fill the rest up with distilled water and drive away. after first drive check fluid level and top off as necessary. you should be fine after that