Running in rebuilt engine

Q.  I’ve got a 1999 Nissan GU Patrol. It was originally a 2.8TD but I picked up a TD42 out of a rolled ute for $2,000 (actually got the whole truck for $4,000, and I parted out the rest of the running gear). I have been rebuilding the engine on a stand in my garage on and off for the past year, and we’re almost finished swapping it into the Patrol. She’s been rebuilt from the block up – new bearings, pistons, rings, hone, brand new head, etc. I’m a little worried though, as I have spent an absolute packet on getting this engine redone and now it’s almost time to fire her up. What sort of run-in process would you recommend that I do to ensure the engine lasts as long as possible?

A> ‘Running In’ is a very misunderstood process. Nowadays with the changes in technology pretty much there is no special ‘Run In’ period. Just make sure that when you run the engine you vary the loads for the first 1000 or so km. In fact it’s best to forget that you have rebuilt the engine and just drive it as normal. Just don’t ‘thrash the engine meaning driving at heavy loads and high engine RPM but also do rev the engine out from time to time through the gears to 3000 RPM or just over. Probably also don’t let it idle for long periods. As far as oil goes that nice old engine needs only good simple oil. Just as an example, Shell Rimula X is a good all round oil so something like that. You want the engine to wear in so don’t use any friction modifiers in the oil yet. Again pretty much drive it as normal.