Priming New Oil Pump - How to?

[Captain Obvious]

Yup. Unfortunately, it means installing the pump without it's drive shaft, priming the system, and than pulling the pump again to reinstall it's drive shaft. It's a pain, but effective.

Here's my oil pump replacement: http://www.classiczcars.com/forums/thread45302-2.html

[Captain Obvious]

Something else I did a little different was my pump installation procedure.

After I was done with the priming process, I pulled the pump out, dumped most of the oil out of it, and while it was mostly empty, put the drive shaft into the pump, aligned the shaft punch mark with the oil hole, stuffed the shaft and pump up into the engine, used one bolt to hold it loosely in place, and verified that the distributor drive tab was where it belonged. So far, other than putting the pump in mostly empty, everything is by the book:

And then here's where I veered a little from tradition. I clipped a small pair of vice-grips onto the distributor end of the drive shaft and used some masking tape to hold them temporarily into place. This allowed me to pull the pump back out without the drive shaft coming with it:

Why? Two reasons. 1) Because the pump alone without the shaft is smaller and easier to handle. Less risk of dumping out my priming oil, and 2) Because now I could put a little gasket sealer on the pump gaskets and not have to mess with getting the distributor shaft in the right orientation. I didn't want to smoosh the gasket sealer, only to find that I had to pull the pump out again because the dist drive wasn't in the right spot.

It went like this:

I pulled the pump again after clipping on the vice-grips, gooped the mating surfaces with sealer, refilled the pump to almost the top with oil, stuffed it back up into the engine for the final time, in and tightened all the bolts. Only other detail to keep in mind is that you cannot rotate the pump internals during this process or the tab on the driveshaft won't line up with the pump slot. Just pour oil into both sides of the pump, but don't rotate the internal gear and rotor.

One last thing I forgot to explain why the first thing I did was take the pump apart, and it goes like this... I did a little searching for Melling pump topics on the Z forums, and there are threads on both zcar.com and hybridz that indicated it would be a good idea to check the pump end clearances before installation. Members jeffp, Pyro, WangsMan seem to be the ones most involved, and here are some of the threads I found:

http://www.zcar.com/70-83_tech_discussion_forum/cast_iron_oil_pump_689487.msg1279920.html

http://forums.hybridz.org/index.php/topic/88729-truth-on-l6-oil-pumps

http://forums.hybridz.org/index.php/topic/61680-kameari-high-performance-oil-pump-worth-it

So anyway, I took the pump apart, deburred all the razor sharp machined corners (pet peeve), lapped the mating surfaces to check for high spots, and checked the end clearance. Lapping the mating surfaces highlighted that there was some metal upset when Melling pressed in the two locator pins, and once that was ground flat, the rest of surfaces were good.

And for the end play, I measured .002 cold, so I think I should be OK. Also for posterity, the thickness of the Melling gasket, and came up with .006 thickness. Then I measured the Datsun gasket from my old worn out pump, and it is .004 thick.

[siteunseen]

Yea I rolled the front wheel of my engine stand onto 1" of floor tile so hopefully the oil all drained back to the pan and I'll only loose what's in the pump.