Little bubbles in header tank no coolent loss no over heating heater matrix perment cold

[Stephen beer]

Little bubbles in header tank no coolent loss no over heating heater matrix perment cold please could anyone help Stephen 

[Texas]

Has any work been done that relates to the cooling system?

[Texas]

What are we talking about? 200, 220 or 250 IS?

[Texas]

I see in your profile it’s a DERV, afraid to say diesels are Not my forte and I would suspect head gasket issues ( v common problem on this engine manifesting in numerous ways)

Could be very minute leakage of combustion gases into coolant system showing up as these ‘bubbles’ and an ‘air lock’ as occurred in heater matrix to cause loss of heat output. Like I said not my area and I’m sure someone With a derv might enlighten us soon!

[Texas]

16 minutes ago, pope111 said:

Head gasket gone. 3k+ job for decent repair, worst case new engine or scrap the car

Harsh!!! ( I didn’t have the heart to put it as bluntly as that ) but sadly probably true....