Brown foam
 

Can someone tell me what is causing this?

The car is not using any oil . Still really clear and no sign of emulsion under filler cap.
The coolant is not being used - this has gone brown with what I though was residual rust.

In the top of the expansion bottle there is some brown foam / looks like chocolate mouse

Does it just need a good flush or is it something more sinister?

I reckon that is a rust fudge mate emulsified oil/water really does look like mayo so I don't think it is oil....just needs a good flush.

Thanks. I will order se more antifreeze and get the hosepipe out.

I have had a few shakedown spins so far so hopefully I can come past soon with your brackets.

I have also invested in a gopro camera so I'm putting together some footage of my hoons

David

thats just rust dust

i would try just flush out witha hose and run a few times trough with water to try and get as much out if its bothering you

then fill with new antifreaze and as pure water as possible

Thanks for the replies. I gave it a good flush yesterday and all kinds of brown muck came out . I will give it another flush before I put it away for winter

David