Rebuilt 4.0: prime before cranking?

Ready to install my 4.0 after overhaul for cracked 0331. New parts include: pistons/pins; rings; all bearings; cam; lifters; oil pump; head [J&C]; head bolts; gasket set. Crank needed a light polish, and cylinder hone was still good. Old pistons were scuffed and oil pump intake screen covered in sludge after 130k. Vehicle came to me at 116k.

Mechanic who's helping suggests oil priming by spinning pump with an adapter inserted through the distributor drive. FSM seems not to mention this step.

If necessary, can this be done with the same adapter and procedure that he uses on SB Chevy blocks?

tia,

summit94

it is allways a good idea to prime the pump first. not only to make sure you fill the pump and make sure you get oil pressure, but it will also bring oil to the bearings. i have a couple prime tools store bought, and have made my own with old distributors by taking them apart and just using the housing and shaft. either way you should prime it first.

prime it with the valve cover over. when the oil comes out of the push rods (all of them) then its time to start up the engine

Priming is the best, but if no other options, pull the coil wire and crank it over for a few seconds until the oil pressure comes up.

old_man said:

Priming is the best, but if no other options, pull the coil wire and crank it over for a few seconds until the oil pressure comes up.

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Or unplug the CPS while cranking. When you see oil pressure, plug the CPS in and give her a go.

If you are going to crank for any extended period of time, pull the fuel pump relay otherwise you will end up with wet fouled plugs.

old_man said:

If you are going to crank for any extended period of time, pull the fuel pump relay otherwise you will end up with wet fouled plugs.

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Not if the CPS is disconnected.

The reason for spinning the oil pump before hitting the starter is to get lots of lube to crank, cam, valve train, etc. before those parts grind on each other. A quick peek into the "distributor" hole suggests that a tool can easily be fabbed to spin the pump with an electric drill. This leads to one final question:

Should one spin the drill clockwise or counter-?

tia,

summit94

Clockwise

old_man said:

Clockwise

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Yep. That's the same direction the dizzy spins.