Rover owners: Injector no1 wet

Im due to fit SDIs soon but upon closer inspection of the injectors in the car it seems there is a "leak" near injector no1. At first I thought it was a bad copper washer seal but now I'm not sure. Then I thought coolant leak/cracked head or block. But I've wiped it up and had a smells and it does not smell of anything. So I've ruled out a diesel leak but I'm not really sure what coolant smell like. I'm more inclined to think it's an oil leak though, as it appears to start from the filler cap I.e it's running from the cap and down the front of the head, into the injector well and down the block. On cold mornings the when I start it, it takes a good 6-10 seconds for the oil light to go out and the engine to "quieten" down slightly. So bad oil pressure= a leak some were!

I didn't want to fit the SDIs if it a cracked block/head if it is coolant that is leaking from somewere, although I haven't noticed the reservoir go down at all.