Need New Oil Pump - Recommendations?

[Bonzi Lon]

From what I've read, the metal composition of the cam is where the problem starts if there is a lack of ZDDP in the oil, not the pressure or the amount.

Bonzi Lon

[Lazeum]

I've seen your topic, it looks really good. On my engine, it is a stock spray bar that looks to be in good shape.

Regarding my case, I'm just saying damage came from the top end but I'm not sure the root cause is there also, it is most likely on the bottom end. Since it did not really know and damages were on head & bottom end, I've redone everything

[Captain Obvious]

I ordered a new oil pump a few days ago and I've been waiting for it to arrive. siteunseen, thanks for the recommendation for the Melling pump. While waiting, I've been thinking about that priming the pump process I've seen mentioned. Sounds like a great idea, but I've got a couple questions.

I got the general procedure... Put the pump on the block and then spin the pump with a drill via the distributor hole. But...

I'm assuming that the priming operation has to be done with the shaft between the pump and the distributor removed or the drive gear that normally spins the pump would try to turn the motor over, right?

My shaft is currently out, but it came out the bottom with the old oil pump. Does that shaft have to go back in from the bottom, or can I slide it in from the top after the pump is bolted into place?

[Jeff G 78]

Shaft has to go in with the pump from the bottom.

[Captain Obvious]

Shaft has to go in with the pump from the bottom.

Cool, thanks. But when that shaft is installed, the gear on it meshes with another gear on the crankshaft, right?

So then what is it that keeps the oil pump shaft from having to backwards drive the entire engine through the crankshaft gear while you're spinning it? Seems like a pretty heavy load on a shaft that small. What prevents you from turning the entire engine over with your handheld drill?

What do you do? Pull all the plugs to reduce the load and just go ahead and let the engine spin? Still seems like an awfully large load for that shaft...

I'm assuming I'm missing something simple here, but I don't see it.

[Jeff G 78]

I'll wait for someone else to chime in, because I don't have the answer. I would never attempt to turn the pump shaft while it is engaged. I don't pre-lube my engines with the pump. I simply fill the pump with oil and use a good quality pre lube on the bearings and valvetrain. I use the white Lubriplate grease.

[Captain Obvious]

Well I feel a little better at least that I'm not missing some completely obvious. (After all, I'm Captain Obvious).

My engine is assembled. I could pour a half quart of oil over the cam lobes right before I try to start it, but I'm not going to pull the cam or crank to smear assy lube on the journals.

Options that I've come up with:

Pop the drive gear off the shaft - Works if the gear is pinned onto the shaft, but from what I've seen, some of the pumps press the gear on without a pin and I don't want to mess with that. Also, since the shaft cannot be installed from the top, this means you would have to pull the pump back off to get the shaft out to put the gear back on.

I think I read a post somewhere that said to put the pump on without the shaft at all and use a long screwdriver to turn the pump directly - Again, I believe this means that you would have to pull the pump back off to put the shaft in.

So what's the secret? Anyone?

[siteunseen]

This is from member "steve91tt", "The OEM pump will move lots of oil. If it were me I'd clean it up and put it back on. If you find you don't have good oil pressure then swap it for another. The pump is easy to change with the motor in the car. If you are worried about oiling I would remove the distributor/oil pump drive shaft and turn the pump with a power drill. You should get lots of oil through each of the holes in the spray bar in the head. When I did this with mine I was surprised to see that oil was leaking out around the spray bar fittings thus reducing the oil that made it to the cam. I made a tool to turn the pump by cutting the handle off of a long flat blade screw driver. I picked one up at sears for a few bucks. Works great."

Maybe he will see this and tell us because I'm not sure either. In Tom Monroe's book he notes that you must "time the oil pump" with the shaft's mark and a mark on the pump's tube. pages 134-136.

Edited March 9, 2012 by siteunseen
more info

[Jeff G 78]

It sounds like they install the pump without the shaft for priming with a drill and then drop it again to reinstall the shaft. It makes sense.

[Captain Obvious]

siteunseen, Yes, I remember that post. Unfortunately, it's a "proof is left to the student" moment.

Jeff, That all depends on your definition of sense. What would really make sense would be able to put that shaft in from above after the pump has been installed. I know... Not your fault.

I'm not sure what would gained by bolting the pump on, spinning it until oil starts to flow and then taking it back off again. I mean, I took this pump off a running engine, and I have not yet drained the oil or pulled the filter. The filter should still be full, the oil passageways should still be full. I can easily pre-fill the pump itself...

Is my situation different than starting a rebuilt engine for the first time where everything is bone dry?

[siteunseen]

Since mine is on an engine stand I would be able to do as Jeff suggest, install then remove then reinstall fairly easy. Captain Obvious's situation makes me think I wouldn't loose too much oil by removing the pump anyway. Thank you both for the information.

Edited March 10, 2012 by siteunseen

[Captain Obvious]

I lost a surprisingly small amount of oil.

Obviously, I lost whatever the capacity of the full pump was, but other than that, It didn't seem to drain much. I truly expected it to weep and weep and continue to drain for days until the entire pickup tube assy was empty, but it didn't. Don't know if it's just me, but once I dropped the pump, it was pretty much over. It did not continue to drip.