I purchased my DiscoII 2003 a year ago and it started over heating and have always noticed a little more moisture out of the exsaust than normal, however no humidity. I replaced the Thermo and it ran fine. 3 nights ago with five 12 yo in back plus camping equipment I looked down and the red light was on and the needle was below the blue line as if broke. I pulled over and, once the smoke cleared realized I blew the Throttle defrost gasket. The next day I replaced gasket and all the upper and loweer expansion tank water pump hoses boiled the Thermo to make sure it was opening. Reaserched on bleeding coolant system. I started it, and seemed as though the preasure in the upper radiater hose was dangerous so I kept realesing pressure manually with the cap. I decided to stop releasing pressure, and took a drive and it over heated in two blocks. While I was driving I noticed major coolant coming out of tail pipes. Removed all parts down to the heads, this is next, my valve covers were covered with the peanut butter on the inside and coolant. What does the peanut Butter mean??? Is my motor shot? You could tell it has been building for some time. I also noticed when I took the Pleneum off there was oil, and when I removed the gasket I noticed the oil was jumping the first three intakes and last three.... PLEASE HELP!!!! I love this site I have read it for months and thought working on this engine would be hard but with guys like "YALL" on here it makes it a hobby. Thanks Everyone


Arkansas
Disco II Tail All Electrical Replacement Front to back
Thermo, All coolant Hoses, Throttle Defrost,

 

You have at the min a blown head gasket, the "peanut butter" is motor oil mixed with engine coolant.
Replace the head gaskets and if it still does it then your engine is toast from being overheated.
These engines are all aluminum and they do not take well to being overheated.

 

Thank you Spike 555. That is what I'm thinking. I will keep my fingers crossed get them planed and new head bolts and go from there, Keep ya posted