Degas bottle question

[LS813]

I am trying to bleed the coolant. I noticed where the top hose connects, the metal tube inside the tank is no longer connected. its just laying inside the degas bottle. Could this be the reason I am having such a hard time bleeding the air out?

[LS813]

Guess my question is. Does the upper hose thats connected to the degas bottle serve also as a suction line? Will it also take coolant from the tank?

[shorod]

What year is your LS, and which engine does it have?

-Rod

[LS813]

2001 3.9

[LS813]

I'm thinking that this is the reason I can't bleed the system properly. If I open the cap on the Degas bottle and push down on the radiator hose, I can here air being pushed out and sucked back in. I think the metal down tube is meant to keep that line submerged in coolant. Being its broken off its above the coolant level, and can draw air back into the system. Am I thinking correctly?

[shorod]

According to the factory service manual for your 2001:
"The degas bottle:

• provides a location for system fill.
• contains coolant expansion and system pressurization.
• provides air separation during operation.
• replenishes the engine coolant to the system."

I no longer have an LS that I can use as a reference, but your suspicion sounds reasonable.

There appear to be 3 hoses connected to the degas bottle. It appears one is the inlet to the bottle, top, and two returns, lower. The inlet hose is connected to the thermostat housing. The return hoses are y-ed together an attached at the DCCV.

-Rod

[joegr]

Yes, you are correct that this is your problem, and it is a known failure mode of the degas bottle.

The hose that connects at the top is the engine air bleed. Any air trapped in the engine should eventually come out here. When the engine cools down, it sucks coolant back in through that metal tube. Since your tube has disconnected, air is being sucked back into the engine instead.