Has anyone come across a round sticker on the core plugs on a 300 TDi engine, It has 6 different temp squares on the sticker, all well & good, but, what colour were they before the engine got hot?? all are a grey colour up to 121 deg except for the 110 deg mark which is silver, any clues...

Hi folks, I've got the head off a 300tdi, but on cleaning the block prior to refitting I was blowing out the bolt holes & the second one from the front inside the cam cover blows into the water gallery, is this normal or just another major disaster?? I have just purchased this LHD 1994 RR clasic...