I've owned half a dozen 4.0/4.6 Rovers but this is the first one I've done a light rebuild on.

I picked up a 2003 Discovery a few months ago with a blown up engine. It's a shame the engine blew up as it was rebuilt about 50k miles before with tophat liners but according to a local indie shop, the block was machined incorrectly and the sleeves sat below the deck a few thousandths. It would appear a broken valve dropped and destroyed a conrod and sleeve.






Either way, I picked up a lower mile Gems engine, a rebuilt set of heads, new cam, lifters, chain, oil pump, water pump, ARP studs, all new sensors and injectors. Almost all the new parts are from Atlantic British or Lucky8. I changed the crank sensor mount to the bosch sensor and also hooked it up to a lower mile transmission and transfer case.

My question is that I will probably be starting it up this weekend for the first time and I want to make sure I do it correctly. I have all the fluids changed and a break in additive in the oil. I packed the oil pump with petroleum jelly but what is the best way to start up the first time?
Should I crank the engine with the plugs out and fuel pump off to prime the oil pump first or should I expect packing the oil pump to do that for me and go with a full start up?
Also, should I jump right into 2000rpm break in speed and follow the cam break-in procedure?
Is the transmission going to be ok being topped of to the fill plug for the break in procedure or should I stop the engine after getting to operating temperature and top it off again or let it drop to idle and top it off?

Sorry for all the questions, I just have a lot of new parts going into this I don't want to destroy right off the bat.

 

Dang that's some carnage.

Same stuff was all going through my head prepping for the first startup...

Here are my 2 cents

I'd say just start her up. Don't worry about priming. I didn't (but I also rebuilt the thing myself, and trusted the assembly lube - it sounds like your bottom end is untouched?). Oil PSI built up within a second - I never saw the oil light. Make sure you filled up the oil filter close to the top before installing.

Bring it to 2k RPM slowly, within a few seconds. Run for 20-25 mins @ 2k RPM. It would be nice to put in an oil pressure gauge for the breakin, if you're not seeing 30+ psi I'd be concerned. The oil light only comes on at ~3psi.

Transmission will be fine, focus on the engine, but if you have the spare hands, it couldn't hurt to top it off during the breakin.

Since it sounds like you didn't touch the bottom end, I'd at least drop the pan first, inspect for any debris, clean it, and clean the oil pump pickup screen.

 

Thanks, Jeff. you are correct, I didn't touch the bottom end or at least changed any parts on bottom end of the gems engine aside from the oil pickup, the gems and bosch engines have different oil pickups. I bought the engine from a friend of mine who is a former Rover tech. He has 5-6 good engines squirreled away in his shop. Everything on the bottom end was well cleaned and lubed after tearing it down to rebuild it as a bosch engine. I also used the 4.6 cast oil pan instead of the steel pan from the 4.0.

I've seen threads where Disco Mike has recommended priming the oil pump with the fuel pump relay pulled on a rebuild before starting. Once I know oil is flowing, I'm not too concerned with the rest of it working.