Head Gasket or Exhaust Manifold?

[mrh123]

My oh so reliable Perkins 4-108 is loosing coolant. My first thought was the heat exchanger as that really is in need of replacement. But after refilling, and with the radiator cap off, I see bubbles which are blowing up a dirty brown foam at the filler hole. Coolant wasn't changed that long ago, but its all gone now, so I just used hose water for the tests to try and locate the leak. A flush will be in order when I've sorted the leak.

Problem is I don't know if the bubbles are due to a blown head gasket or a hole in the exhaust manifold. Is there anyway to tell?

Otherwise she runs fine, starts fine, idles fine. Would she if the head gasket was blown?

Taking the exhaust manifold off isn't a big ask, but would I be able to see a hole?

[DougR]

A compression check might tell you something about the condition of the head gasket...

DougR