strange overheating

[saxxi]

Hey guys,

second problem, hope you can help.

My temp light has been coming on, sometimes quite quickly and sometimes I can drive around all day before it comes on. I had a new head gasket a about a month ago (skimmed etc), and the rad fan always comes on. I have checked the coolant level and also I checked to see if the coolant was bubbling or anything like that when the light comes on and it does not.

When I hold my hand over the engine (forgive me for this, I know absolutely nothing!) the part I put the oil in seems to be the really hot part, even on a really short journey.

Any clues?

[Mochachino]

Air lock in the coolent system?

[masetw]

Bleed the rad system. Open the top of the rap and run it for 5 - 10 mins

[saxxi]

thanks guys, I will pass this info to my mechanic (my dad !!). As a side note, the heater only blows cold air...is this connected or a seperate problem. Only discovered this last night when I went out and needed a bit of warm air

[Beaniemoo]

Definitely sounds like you have an air lock in your cooling system, especially if the heater doesn't work.
There should be a bleed valve in your cooling system somewhere, (I only know VTS's) it'll either look like a tyre valve in a coolant hose or a bolt into the thermostat housing or something (if you tell us what car you have I'm sure someone will tell you where it is), undo that and blow into the header tank till coolant comes out of the bleed valve, then do it up again, then as said, leave the cap off and let the car run for 5-10mins, with the heater on hot (might be worth keeping the revs up) till the heater gets hot.

Hope this helps