Defender TD5 Engine problems, Help!

Hi,
just joined the forum, so hello and thanks for reading my post.

Ive got a problem with my 1999 defender td5, the last week only after standing for overnight been having huge cloud of blue and white smoke on start up, which sends a large cloud down the street, and by the time shame has kicked in it clears and thats it until the next morning. The engine has done 100k has just a cat pipe, mid box replacement pipe, egr replacement and new pipercross filter, only other strange thing today was when driving i would get to 60 and it would go flat, no power, wheras before it would steam on to 75. then after a drive at struggling to stay up to sixty the heaters went cold, gauge dropped and top hose split and blew all the coolant out, have been losing a little coolant lately too, any ideas? any help, tips greatly appreciated

I'm no expert but my money would be worn valve stem seals. The oil slips past the seals overnight and burns the oil in the cylinder on start up.

Oh, welcome btw.

Cylinder head gasket blown as well.

Hi,
thanks for reply, will get those checked, had overheating problems before and head was skimmed and new gasket 300 miles ago, what could have caused the gasket to go again? also top hose was like a balloon when that happened, would the hose gone week because of that, and does loss of power at top speed suggest head gasket because that is the most noticeable problem.
Any help greatly appreciated