Hey guys this is my first post under this name. Was a member years ago but sold off all my rover stuff. I'm back into owning a discovery again.

So my problem is I have air trapped in the system. I can hear it moving around in the heater core. I can and have had this running for hours while camping and the 4 months I've owned this I've never had and heat issues or overheating problems.

I had this noise since I bought it. Figured I'd do every gasket anyway but it does not overheat and the engine is completely dry of any oil leaks. So I just ended up replacing the thermostat with one that has the jiggle valve. I did this and bled the cooling system as described on here.

I have the engine dead cold, jack up the right front corner
Removed the rad plug and the expansion tank cap
Filled the expansion tank until coolant starts to flow from rad plug

this is wear my problem is. It says fill tank until coolant comes out of the rad plug. If I do this the expansion tank is completely full. Is still normal, if so run the engine with all caps off, fan and full and control set to low. So when the bubbles stop(which they do) the expansion tank is still full. Not full to the full mark but full to the top of the tank. I don't get it. Do I suck out the coolant from that?

 

The water flow sound is due to air in the cooling system.

Get the front end up high if you can for bleeding the system.

1. Leave both caps off.
2. Keep coolant to the proper reservoir level.
3. Start the truck with heater on Max, but have the blower at #1 position.
4. Look for air bubbles coming to the surface of the radiator as the thermostat will eventually open.
Put a bucket/pan under car to catch any coolant.
5. Keep coolant to the proper reservoir level.
6. When you feel heat coming from the inside heater vents that is a good thing.
7. Close up the radiator, and put the cap on the reservoir.

A couple of hours later return to car and fill reservoir to proper level.
Remember to be patient with step#4 as the truck will need to heat up to get the thermostat to open.

 

should be....."Fan on high and temp setting as hot as possible."

If your reservoir is not filling the radiator I suppose you ought to check that hose and outlet from the reservoir for blockage.

 

Yeah that's my problem, with the corner jacked up and both caps off. Filling the reservoir to the proper level(which is about half way) the coolant still does not come near filling or flowing out of the rad. I have to pretty much fill the reservoir for the coolant to flow out of the rad.

I can then run it, heat and fan blasting. About 20 min, I have wicked heat and no air bubbles from the rad. Put the rad cap back in but the reservoir is still over filled. I'll pull some hoses off and see if I have something kinked but I didn't see anything that looked kinked. Maybe I'll flush the heater core. I have awesome heat and like I said I can run this beast for hours at a idle and it does not overheat