My jeep starting overheating. The coolant level is low which I know can cause overheating. However its an orangy brown color and there apears to be mud in it. The gauge maxs out 260 then suddenly shoots back to 210 after awhile leading me to belive that the thermostat is sticking. Does anyone have any suggestions? Also how would mud go about getting into the radiator?

 

Orangy brown stuff means the coolant hasnt been changed in years. I recommend coolant flush, new coolant, hoses, tstat and rad cap to start. Fix the reason you have low coolant

 

The coolant has been changed though. I did a radiator and a head gasket within the past year. I assume it changed color from the mud but im not sure how it got in. As far as the low coolant im not sure about that but I haven't seen any leaks and as I said I just did the head gasket and there's no sign of coolant leaking into the cylinders or oil.

 

Was it re-filled (in the past year) with 100% water or 50/50 mix antifreeze/water? Old cast iron blocks/heads gotta have good corrosion protection. Seems odd for a year old (or less) correctly flushed/refilled cooling system turning brown/muddy so quickly.

 

Drain the coolant, fill with a 50/50 mix of vinegar/water, turn heat to full hot, let it idle with cap off watching the rad level refill as needed, youll see when the thermostat opens, as the coolant level will drop noticebly. top off replace cap go for short drive. Drain, repeat as needed. Refill with 50/50 anti freeze/ water. Also check while idleing for leaks, when you drive it can be blown dry. Also do a pressure check.

 

sounds like oil in the coolant, you probably have a blown head gasket.

 

I agree, also you might smell check the vapors when removing the radiator cap. You smell oil? Or do you smell exhaust? You shouldn't smell either. But then you might smell both when a head gasket is blown.

 

Get a "block test" performed. It is where the coolant is sniffed with specialized equipment for the presence of hydrocarbons (oil).

NAPA even sells a do it yourself block test kit for about $45

The overheating may have been the cause here. You could have a blown head gasket or a cracked head.