I agree with Dodgeman, but I'd like to add my $0.02... 6 amps will get you a 30-37 gpm pump according to the Summit catalog, for a measly $260. You're probably going to need to upgrade your alternator unless you already have one makes sufficient juice to run headlights, heater, wiper and waterpump at an idle. My guess is that's about 30-35 amps, at an idle. Need to understand here, alternators aren't rated at idle, so take that into account. Dodgeman is correct in that you'd have to run a belt drive on an electric waterpump as there are no pumps marketed specifically for the "A". That means with an electric pump, you'd have two belts instead of one. (you do want to keep the alternator, right?)

My opinion is that at idle, it's going to take more power to run an electric waterpump, and at rpm it will save power at the expense of coolant flow. Then you have the complexity of another belt drive and electric motor with wiring. Seems like it would be a whole lot simpler to run an underdrive pulley on the waterpump. Any competent machinist could make one for a fraction of the cost of an electric pump.

I'd be really interested to know if that cam works in an A14/15.

Good info Dodgeman, as I'm finding that cams are a little hard to come by in the US. Thanks

Not mine, and I don't know if it'll fit a Datsun. He says it's 49.25" wide at the flanges. 4.62 gears and a mini spool and supposedly everything is new. 114 mm bolt pattern.

ebay link

Dodgeman, I just realized that we may have some confusion because you're in Aus and I'm in the US. Someone correct me if I'm wrong, but I think the 1200 A12 ended here in 1973. In 1980 or so, we got the A12a. The only GX engine I'm aware of here was the 1978 B210GX with an A14.

So now I'm wondering if the A12GX cam will fit an A14? There's been one on ebay lately.

A12's have the distributor in a different place than the other A's. The distributor gear won't be in the right place. Oversize bearings are for worn crank or rod journals. If they have to grind the crank, you'll get oversize bearings.

I don't know anything about lightweight lifters. But I wanna!

Hmmm...
a pub...
a woman...
a little whoopee...
a bun in the oven...
you'll need more money Woody. Might be the last time we hear from him.

Would have to make a fixture to keep the piston from popping out and bleed it with the nipple up. Then bolt it in the car. Should be the only time you have to bleed it.

Too bad it's not around here, I would have liked to pull it apart and see what makes that happen.

Get your alternator tested.
Do not disconnect your battery with the car running. It's a good way to toast any electronics you have in the car. The battery acts as a reservoir and eliminates voltage spikes. In addition, if the battery is charging when you disconnect it, the hydrogen gas and a spark will cause a very nice explosion and you will have sulfuric acid all over you.