Sorry if this board already has one of these threads, searching didn't find it.

Anyhow, here's a vid that piques all my interests

https://www.youtube.com/watch?v=vx6hmSclbRE

I picked up an AVA2. It's actually the one referenced in this thread: https://www.smokstak.com/forum/threads/petter-ava2-12hp-diesel-came-home-with-me-today-look.79162/

I didn't realise it hadn't been run in 10 years!

Anyway. Dismantled, cleaned up and freed 1 of the IPs that was pretty much rusted in place, both injectors, the oil pump, drained the water and sludge out of crankcase and filled with good clean oil, bled all oiling lines, primed all fuel lines, checked injectors... everything to do so it should run.

I'm in the process of fitting a flywheel and starter to it, as it doesn't have the 4:1 gears some of them have for a starting handle, and I haven't managed to spin it hard or fast enough to start by hand. There is the 2:1 reduction for the camshaft, but adapting  a handle to that seems like more work than the starter and unfortunately I don't have a suitable pony motor.

I will post photos later.

But my question for now, if anyone knows, is what should the injector nozzle recession (?) be...

I picked up 2 different thickness copper washers (only one injector had one fitted. They also have an aluminium heat-shroud, which I would think would be enough to seal up on) and fitted them both with the ones matching the one I pulled out, not sure how good this is going to get the spray into the cylinder though as it may be rebated too far?
Also not sure how or why the need for copper between the injector, the alloy, and the head. Could/should I do away with it?

Being air-cooled I can see the sense in heat-sinking the injectors, it's just not a set-up I've come across before.