Vauxhall combo over heating

[tangerine77]

Hi all, just wondering if someone can give me an idea what is wrong with my van. It started overheating on the motorway and got that hot it melted the water hose. I have replaced the hose when i was doing so i noticed the fuse for the radiator fan had also blown. I filled it back up with water and went on the motorway when after about 5 mins the temp was in the red and the water in the water tank was boiling when i removed the lid and the radiator fan was on and working. There is no oil in the water, the oil isn't creamy and there is no white smoke from exhaust which iam hoping rules out the head gasket. Are there any simple things it could be?
Thanks

 

[gmangt4]

Is there bubbles in your expansion tank on idle?

 

[tangerine77]

Hi thanks for reply. I have just been and started van and there seems to be a few air bubbles although very tiny.

 

[gmangt4]

Get someone to rev it up and down with the expansion tank cap off and see if they change with the revs

 

[inbed79]

Is there bubbles in your expansion tank on idle?

and if not try fairy washing up liquid the bubbles last longer lol

 

[tangerine77]

Will give that a go in the morning, is it likely to be an airlock if the bubbles increase?

 

[gmangt4]

No, if they increase with the revs then its most likely a cracked head, porous head or more than likely the head gasket, the test will tell you if its gone between the combustion chamber and a waterway, they dont always go between the oil way and waterway causing emulsification of the oil, it can confirmed by using an exhaust gas analyser over the radiator cap and check for exhaust fumes in the air coming out, or a compression test.