kjc

May I suggest you kill the power to the fuel pump as opposed to pulling the coil wire? I would think that pumping raw fuel into your cylinders while cranking your engine to prime the oil pump would be less than ideal. What do you think fellas?

cruiser54

Correct, maybe. And the oil galleries will fil lup in about 20 seconds while cranking with the coil disconnected. The existing oil film on the bearings will provide more than enough protection for the 20 second period.

cruiser54

That would work, too. Not a bad idea. They build oil pressure quite quickly though.

MBode1

When changing the oil, the oil filter is empty (or partially) and has to fill itself and the passages going to and from it. That's why it takes a few seconds for the pressure to come back up. IIRC.

rrich

Yes the cam is broken in. But without oil on it, it will wear in further. When the pump is removed, the oil galleys drain, so NO oil gets to the cam for quite a while.
At least 50% of the total wear on the cam occurs in the first 5 minutes when new - and when installing a new cam you coat it with tons of grease. After a pump change you don't normally coat it with grease - it's dry! There's not alot of room left to break it in again.

But don't believe it - just be ready to put a cam in it. Packing the pump with Vasoline helps the pump get pumping fast.

Take the chance - or drop the pan and pack the pump with Vasoline.
Feeling lucky? Would you win in Vegas tonite?

Johnnytsunami801

I know this sounds stupid but I'm not very mechanically inclined where is the coil wire located... I need to prime my new oil pump can some one send me a picture

Bustedback

On the coil.

mentalbreakdown00

I totally agree with serious. You need to pack an oil pump with grease or vasoline or something. But due to his limited skills id say pull the ASD relay spin it over until it just does register some pressure, then stop reinstall relay and fire it up. Dont just pull the coil wire disable fuel....

DFlintstone

Yea, from the coil to the center of the distributor cap.

cruiser54

No need to pack the pump.

Disconnect the CPS. Crank til you see oil pressure on the gauge. Plug the CPS back in and fire it off.

DFlintstone

Cool idea. Also, if I had a 99 I think I'd like to know where my ASD relay was. Pulling that would do it also.

Johnny, that relay controls about everything. About anytime your Jeep won't work you might check/swap that.

Myself, I'm not positive the CPS connector on a 99 is on the left...I just don't know.

bigbadon

No need to pack the pump. Melling does not recommend this anyway.
This isn't a new rebuild so there is plenty of residual oil on the bearings. Just kill the ignition or fuel and turn it over.

5-90

1) While you had the oil pump out, you should have removed the cover and packed the cavities between & around the gears with grease.

2) To properly prime the oil pump, you would remove the distributor, valve cover, and oil pressure sensor. The hose for a mechanical gage would replace the oil pressure sensor. You would run a priming rod down through the distributor hole (options are the centre shaft removed from another distributor, or a Small Block Chevvy oil pump priming rod with the collar removed,) engaging the drive tang with the oil pump drive. Then, use a power drill motor to spin the pump - of course, the oil sump would have to be filled for this to work! But, the oil pump should be the only thing turning.

3) Run the pump until you see steady pressure for at least thirty seconds (mandatory,) and until you see oil being delivered to the valvetrain through the pushrods for at least ten seconds (optional, but recommended.)

4) Remove the priming rod, reinstall the distributor to correct timing.

5) Reinstall the valve cover.

6) Start engine. Monitor oil pressure (via mechanical gage) for at least 60 seconds before loading engine - manipulate throttle by hand to make sure that oil pressure follows throttle opening.

7) Stop engine

8) Remove mechanical oil pressure gage, reinstall OPS and reconnect wire.

9) Return vehicle to service.

DFlintstone

I guess even with fuel injection cranking it with the plugs out isn't necessary gonna "flood/rinse" the oil from the rings. Just ramblen'. With a carb there would be no vacuum to draw fuel in. Anyway knowing where your ASD relay is, (if you have one), makes sense. Just pulling that will kill spark and fuel.

5-90

Not recommended! If the engine has "drained down" while the oil pump was dismounted (fairly common happening...) then you're going to be forcing the bearings to move while dry. This will "scrub" the bearings and shorten their lives considerably.

This is one of those things you really want to do right!