Firing up an engine that's been sitting for years

Make sure there is plenty of oil, rather than sludge in it, lower the compression, either by removing the injectors or glow plugs or blocking the inlet, spin it over till the oil light goes out, then start it.

1. Remove all injectors.

1. Squirt 50cc of engine oil into each of the bores using a large syringe.

2. Replace injectors

1. Leave it 48 hours

2. Fire it up.

If it possible to spin up the oil pump without the engine turning, I'd do that first (it's easy on some designs of engine). To make sure it has primed and is moving oil around. If you can get access to the bores, put some oil into them, and spin over before starting.

Ouch, are you sure you mean 50cc?

5-10cc maybe, and even then I would want a very short spin or turn over by hand to spread the oil over the whole bore.

I might also prefer to remove glow plus rather than injectors, and inject any oil through this orifice.

When I part-exchanged a low mileage Peugeot 205 diesel a number of years ago the dealer left it parked up for a few months, maybe waiting for the age to catch up with the miles. When they re-started it the timing belt snapped. I don't know if this was just bad luck (good luck for me!), or maybe the camshaft was stiff because all the oil had drained into the sump?

Sounds like a pretty sure way to *wreck* an engine! Yes, it's a good idea to get some oil into the bores, but not *that* much! Diesel engines have very little clearance between the crown of the piston and the cylinder head, so I would guess 50cc of oil (incompressible) is far more than the available capacity at TDC. You'd better hope the battery is on the way out or something is going to break. Al's assumption that the oil would drain away over 2 days is an assumption too far to my mind. Thin oil, quite possibly; engine oil.... I doubt it.

Agreed.

Why do you say that? Just curious...

the belt can rust onto a pulley or the water pump can seize, as can an idler or tensioner, but not something you would be likely to check first.

because injectors can need an air hammer and major dismantling to get them out, glow plugs are usually less problematic.

Does it turn "by hand", as it were? One thing which can happen is for the piston rings to rust in the bore. My personal fix for that would be to add a generous dose of thin oil (not necessarily penetrating oil), perhaps 100 ml per cylinder, and leave it for a while, ideally weeks. And then make sure the engine can be turned (spanner on crankshaft, rolling car in gear, etc) before doing anything else. Obviously, with a diesel you would need to remove the injectors (much easier with a petrol engine!). You might need more oil if the cylinders are inclined, the point is you want the whole top of the piston covered.

Once you have got the engine turning by hand, spin it for a while on the starter *with the injectors and/or glow plugs removed*. I should have added that to my earlier post.

With the proviso that you don't want a hydraulic lock, you want as much oil as possible on the pistons, rings, and bores when you start running, IMHO.