Overheating - common problem but need help

[Joles123]

Hey guys hopefully someone can help me to save time ripping things apart.

I have had the quite common problem of overheating in my VX Supercharged V6 (L67). A week or so prior I had noticed I had been leaving coolant leaks on the passenger side. It wasnt until my car overheating that I discovered that the plastic inlet pipe to the heater tap had broken off and was leaking out coolant. I changed the tap, heater inlet hose and decided to also change the upper and lower radiator hoses while I was at it. I didnt remove the knock sensors while draining as its a pain in the ass. When I back flushed through the upper hose i didnt get a lot coming back out the outlet hose. I'm not sure if this is because the knock sensors where not removed.

Now when I have filled it back up with coolant it didnt take a lot (didnt expect it to take the full 12L capacity) but it was only a about 3-4 litres. Then when I started it its still overheating. I bleed all points except the thermostat housing as my boost valve is in the way making it impossible to get a screwdriver on it!

I noticed when the engine is cool that the radiator level has dropped. I havent run it without the cap on to see whats happening to the level. One interesting thing is with the overheating is that the upper radiator hose and transfer pipe stay completely cool but the heater hoses are hot. Is that normal?

Would these symptoms be caused by the fact that I havent bleed the thermostat housing? Or should bleeding the other two points be enough to eventually get the air out? The only other things I can think of is theres a blockage somewhere, the thermostat is broken, the lower inlet manifold gasket is leaking or the water pump is stuffed?

I'd really like to hear some opinions before going in to change the manifold gasket or water pump and finding it was ok. Any other tests I can do to rule things out?

Does anyone have any tips on getting to the thermostat bleed screw without removing the u-bend. The boost valve rear bracket bolt is also impossible to get off theres no clearance.

Thanks for your help.

[apathy]

Hey guys hopefully someone can help me to save time ripping things apart.

I have had the quite common problem of overheating in my VX Supercharged V6 (L67). A week or so prior I had noticed I had been leaving coolant leaks on the passenger side. It wasnt until my car overheating that I discovered that the plastic inlet pipe to the heater tap had broken off and was leaking out coolant. I changed the tap, heater inlet hose and decided to also change the upper and lower radiator hoses while I was at it. I didnt remove the knock sensors while draining as its a pain in the ass. When I back flushed through the upper hose i didnt get a lot coming back out the outlet hose. I'm not sure if this is because the knock sensors where not removed.

Now when I have filled it back up with coolant it didnt take a lot (didnt expect it to take the full 12L capacity) but it was only a about 3-4 litres. Then when I started it its still overheating. I bleed all points except the thermostat housing as my boost valve is in the way making it impossible to get a screwdriver on it!

I noticed when the engine is cool that the radiator level has dropped. I havent run it without the cap on to see whats happening to the level. One interesting thing is with the overheating is that the upper radiator hose and transfer pipe stay completely cool but the heater hoses are hot. Is that normal?

Would these symptoms be caused by the fact that I havent bleed the thermostat housing? Or should bleeding the other two points be enough to eventually get the air out? The only other things I can think of is theres a blockage somewhere, the thermostat is broken, the lower inlet manifold gasket is leaking or the water pump is stuffed?

I'd really like to hear some opinions before going in to change the manifold gasket or water pump and finding it was ok. Any other tests I can do to rule things out?

Does anyone have any tips on getting to the thermostat bleed screw without removing the u-bend. The boost valve rear bracket bolt is also impossible to get off theres no clearance.

Thanks for your help.

replace the thermostat first and they are only about 15 dollars from supacheap and an hour of your time

[Tree cutter]

If air is trapped around your thermostat then it will not work. The thermostat will only open when it has coolant touching it