Any advice on finding oil leak

Bought my first D2 TD5 and it had some oil underneath RHS engine and on top of alternator. Figured it must be coming from injector harness as ECU plug was full of oil as well.

Changed injector harness and gasket and oil seemed to stop dripping from underneath. Also changed front cam inspection cover as it was very loose.

Alternator then packed up so fitted new one with new vacuum pump as well. Then noticed more oil drips from below alternator area. The oil feed to the vacuum pipe has a new screw through the banjo and new copper washers (1 each side). I re tightened this just to make sure but the oil continues.

I'm guessing the oil return pipe might have a leak but how the hell do you see down there with engine running?

Is it safe to run engine for a short while with the viscous fan removed and pipe connecting to the inlet manifold removed as well (I replaced EGR valve with pipe)? If so I should be able to get a hand down there to feel for a leak, especially if I do a clean up first

If not oil return pipe anything else around that side of the engine that could be leaking? The new gasket is clean and I cannot see any oil around the top of the inlet manifold so it is leaking from somewhere further down. I just don't know what else is down there.

BTW It is definitely engine oil and not diesel as I have had to put another 2 litres in over the last 1000 miles

Thanks John

perfectly safe

Not sure where it is on a Td5, but I had oil pressure switch on VW LT van which leaked a surprising amount of oil through the body, rather than around the thread. Worth eliminating the possibility anyway!

Thank you for your input

I'll have a bash at the weekend and report back

I know the oil cooler is on left of engine so assume oil pressure switch is there as well?
Anything else on right side of engine below inlet manifold height?

Its probably from the back of the rocker cover.coild also be a leaking fpr and washing down back.

Found a split in the vacuum oil return pipe and replaced it but still have some oil dripping from around that area.

Removed vacuum pump and there was oil coming from the alternator where the splines of the vacuum pump insert.

Should oil be getting there in the first place and if so what stops oil leaking from between alternator and vacuum pump interface as I don't see any seal there