Thermal issues, aka over heating question

[rkleypas]

I'm sure it's something real simple, and hopefully someone here can help. I've been having over heating issues since the Power Tour. LS7, twin e-fan Be Cool radiator. Gauge is showing 250 degrees after idling five minutes. Fans are running and temp keeps climbing. The funny part is the lower hose and lower part of the radiator aren't hot at all. There are some black flecks in the anti-freeze. Bad water pump? Thermostat? Air bubble? The cam was swapped to a milder one before the tour.

[dontlifttoshift]

Sounds like a gauge problem.

[Che70velle]

Cold spots on radiator body usually indicate an area where coolant isn't flowing through, as in a blockage. Are hoses building pressure? What water pump are you running?

[MarkM66]

Have you opened the system recently? A quick heat up at the sensor can sometimes come from an air pocket.

[rkleypas]

Are hoses building pressure? What water pump are you running? I can squeeze the hoses when it's running. The upper one is hot, the lower hose is room temp after 5 minutes of idling. Not sure if I should be able to or not? The pump is the Wegner accessory drive water pump. Less than 3,000 miles on it.

Have you opened the system recently? Yes, the cam was swapped out before the Power Tour. Never had an issue before that.

Could the thermostat be sticking or bad? Never looked at an LS thermostat, but there are flecks of black rubber in the radiator.

[Vince@Meanstreets]

You might have a gauge or sending unit issue. Never seen a LS get to 250 that fast idling. One hose should be hot @250.

Borrow a thermometer and verify temperature.

Then get the air out of the system.