Sorry to hear about your enjin,here are some pointers if I may.
The pump has got markings inside the cover,they need to line up.The enjin at tdc(top dead centre,fire at nr one.)you will find the markings line up on the pump and drive gear.Dont get it wrong it is not only hard work to fix in the car but difficult to see the gear/marks.Take care for the gears are helical and throw you off fitting the pump.If your enjin's has a vacuum pump under the fuelpump,remove it,it will make life easy with the fuelpump.The vacuum pump has no markings.( no timeing needed)
Send the pump with the injectors to a diesel shop to check the fuel delivery and injector pressure/spray.
The block can be re-sleeved.All the parts you can buy from Masterparts.You can buy a sleevekit(sleeves,pistons and rings) for R6500.The rest you can get from them to,bearings ,gasgets etc.The gasget set are a R1000 and the head gasget are the same as the agents.(inside the set.)You can buy loose sleeves and pistons,but then you need to ask for the Nissan 2.7 parts.Only buy two more for your 6cyl.The 2.7 are a four cyl. and you will be supprised of how many parts will fit your 4.2 for a fraction of the price.They do not have precoms for the 4.2,but they have them for the 2.7 and it fit perfect in the 4.2 head.You have to buy two extra,at R50 a piece.If you need them.Look for cracks on the head @ the precoms.If so,you can knock them out with a 5mm punch from the injector side with ease.To fit the new ones,put them in the freezer for a half hour,and do nothing to the head.(no heating).Only clean the holes where they fit.Drive the new precoms with a soft mallet into their holes till your hear the change in sound.Then you know they are home.The head need to be skimmed after that,because the precoms will stand proud.The specs say precom protrusion are -0.05mm.Dont try to get that,some engeneering guys get it wrong and can mess up your head and head.
Fitting the sleeves are simple and engeneering has to do that.The sleeves HAS TO PROTRUED THE BLOCK.According to specs 0.02-0.09mm.
The rest is straight forward.
Set the pump with a dail guage nr one at tdc fire.The pump must lift the guage 0.76mm @ tdc.To get that, zero your guage and turn the enjin anti-clock,make sure the guage are zero,turn the motor clockwise to tdc fire at nr one.On tdc the guage must have a reading.If not turn the pump only to get the lift.(The sloted side) Set the lift @ 0.76mm-0.80mm.Do not go to a full mm.All this is offcause after the pump is fitted on the timeing marks/gears.
The valve clearance are as follows,do it like this,it will make life easy.
Nr.1 @ tdc fire. Set valves 1 2 4 5 8 9
Nr.6 @ tdc fire. Set valves 3 6 7 10 11 12
With this you do not have to turn the enjin for every set,you turn the enjin only one time.
Set the valve clearance 0.3mm both intake and exhaust.That is a hot setting and need to do it again after the drive in period.
Good luck,hope this helps.
PM me if you need anything else.
Rdgs
Frans
