DIY oil priming tool for Jeep 4.0L

[thenag]

Ok so yeah you can just cut the handle off a flat head screwdriver and stick it in a drill, but since I am still waiting on the machine work on my cylinder head I had some time to make something a little nicer.

So when you are building a fresh motor you want to prime the oil pump and system WITHOUT turning the cam and other parts since there is no oil in the oil galleys etc. (if you are just replacing an oil pump you are probably okay just cranking the engine with no fuel but you probably should prime the pump anyway)

So my JY motor was from a 2000 xj with the Coil on Plug (COP). So it doesn't have a traditional distributor. It has a sensor with a gear and a shaft to turn the oil pump.

This little guy


The gear has a pin in it and it comes apart like this



I cut the top off the shaft, drilled and tapped 1/4-20 threads into the top of the shaft. I then cut the head off the bolt so I have a nice 1/4 shaft.



Slide the shaft back in the distributor housing and it looks like this


Put the 1/4 bolt shaft into a drill chuck and slide it into the motor like this;


I am not ready to prime my motor. When I do I will update how well this worked.

This is one of those things that really didn't take that long to make, maybe 45 minutes, but will be much nicer to use than just a screwdriver on a drill.

Nathan

 

[Pile of parts]

Good use of time while you wait on the head. You never would have made that once the head was on, out of pure excitement to get it running. At least, that's how it would have been for me.

 

[thenag]

BTW this worked great. I ran it for over a minute as close to the initial startup as possible. The oil pressure gauge came up past 1/2 way with the drill powering it.

I also used the shaft to turn the oil pump so the distributor would drop in correctly.

Nathan