Mystery Oil Leak - advice on where to look please!

I recently got a 19J fitted to my 1984 HiCap to replace the 2.5NA.
The engine is running really well but I get a large puddle of oil on the floor in minutes after being parked up.
I am pretty sure the amount of oil will make it fail an MoT and more importantly, my poor Land Rover has been banned from parking on our new drive until the leak is fixed!
I originally thought the issue was down to the sump gasket, which I replaced but the leak is still exactly the same.
I’ve looked around and there does seem to be a fair bit of round the very top of the engine but it doesn’t seem to be enough to make the puddle I get on the floor.
Can anyone give me any advice of classic leaky places to check?
The engine runs really well and runs pretty cool so I’m hoping it’s not likely to be the head gasket – which is beyond my technical ability! To give you an idea of my technical ability the sump gasket was my biggest automotive undertaking so far!
Thanks in advance!

Clean the engine off & the run till you can see traces.

You have a few places. Crappy oil cap
Leaky rocker gasket,crank breather or rear seal.

UV Dye with UV torch, I need to do the same as I suspect the head gasket is leaking but the oil is everywhere at the moment

Thanks Phil,
I did clean the engine last time and the oil appeared to be leaking from the sump straight away. Looking back I wonder if the oil was coming from the rocker and the oil that fell on the floor was oil that was already part way down the engine.
I will clean around the the top again tonight and then run it for longer and see if it comes out the rocker gasket.
The crank breather it's not connected to anything on my Landy for some reason. I know it's supposed to go into the turbo hose but there's nowhere to connect it on my engine - possibly because the turbo wasn't a 19J one there's no connection for it. I know it's a bit naff but at the moment I have a 3 foot pipe running from the breather into a tub to collect any oil and there's not much.
Is the rocker gasket easy to change?
What's the rear seal, is that an engine out job?
Thanks for your advice!

windy81 said:

UV Dye with UV torch, I need to do the same as I suspect the head gasket is leaking but the oil is everywhere at the moment

Click to expand...

Thanks, I take it you pour the dye into the oil then look for new traces of oil? I have the same issue with oil everywhere!
I am hoping it's not the head gasket on mine as that'll be back to the garage.

@MontyBigglesworth Easy job to change the rocker gasket. There are also 2 1/2 moon inserts to do at the same time.

MontyBigglesworth said:

Thanks, I take it you pour the dye into the oil then look for new traces of oil? I have the same issue with oil everywhere!
I am hoping it's not the head gasket on mine as that'll be back to the garage.

Click to expand...

https://www.ebay.co.uk/sch/i.html?_...0&_trksid=m570.l1313&_nkw=UV+Dye+oil&_sacat=0

The above gives you some of the dye I was looking at.

The dye needs to be oil specific by the looks of things.

Good news:
I've changed the rocker cover gasket which appears to have sealed well. I had to buy a pack of 10 but at only £1 each I can't complain.
Really good news:
I got a lot less oily than when I changed the sump gasket and didn't need to wash my hair in Swarfega.
Bad news:
When I removed the three domed nuts holding the rocker cover on I found the remains of some sort of washer, they felt rather brittle and most of them broke up when I removed them. It's too late now but I even wonder if these washers were what was causing the oil leak all along!
I found the only washers I had that fitted were M8 MUD washers. These didn't sit well and appear to have worked like a sprinklers and sprayed oil all over the place.
I have been trying to find the correct part number but there seems to be a few conflicting options!
232038 May be to old but it's a copper crimp washer
273069 Aluminum washer - looks closest to what came out.
242988 nice copper ones but listed as early series
Does anyone know what I should be using? I'm guessing part 273069
Thanks in advance!

Sounds similar to my my series 3, another leak I sorted was the fuel lift pump , leaking From the lever spindle