Hey everyone me and my buddy where changing the thermostat on my 2001 ford ranger 2.3l truck and realized it was the wrong thermostat so we left it off (coolant was drained with what ever little bit was left in block that didn't drain) couldnt get the thermostat in for 4 days because it was a dealership part and it was saturday. on saturday night and sunday night it never got below 29-25 degrees or so (here in michigan) but he got real worried that the block could crack so we replaced it again with the broken thermostat and put new coolant in and I could still drive it (no heat of course) and its driving fine but it seems like the coolant is a little foamy and dirty after putting bran new coolant in. and i checked the oil and i don't know a whole lot about cars but it had a little bit of white stuff in it only a fingertip's worth and i checked it 7-8 other times and it never showed up again running or not running but it does have a few little bubbles... im worried but it doesn't seem like it got cold enough for the engine to crack and there is no leaks from the thermostat what could this be?
Dirty coolant, just changed thermostat?
If your coolant is still foamy, try to wait a day or so without driving the car to let it settle. Then check to see if there's oil on top of the coolant. If so, that's a pretty sure sign that your head gasket is leaking or your block cracked, allowing oil to mix with the coolant or vice versa. The white stuff in your oil sounds suspiciously like how coolant looks in oil, too.
On the other hand, if you didn't actually drive the car and you have 50/50 antifreeze/water for your coolant, I seriously doubt that the coolant would've frozen and caused your block to crack. I suppose the foam could've just been from some impurities in the old antifreeze. Unless you flush out your cooling system, you'll have a little bit of old coolant mixed in with the new. That's not catastrophic, though, it'll just shorten the life of your coolant slightly.
Dirty coolant, just changed thermostat?
make sure you use dexcool (orange) and not ethelyne glycol (green) do not mix the 2 together. when you change the thermo again flush your cooling system completely including block and heater core.
