Fuel in/out on fuel pump

Just received a new electronic SU pump and a quick lookover leaves me with a couple of questions…

Cannot see any markings at/on the fuel connections showing which is in and out…I would think it matters, does it?

Again, at the fuel connections, they (SU) have an O-ring at the connection whereas I thought it would require a couple of sealing washers on each connection…has anyone used just the supplied O-ring, with sealing washer on the other side of course? Did/does the O-ring seal well?

Don’t remember which way it goes, but try blowing through it, the direction you can get air though it is the direction of fuel flow.

I seem to recall there being something molded into the casting that indicate one of the ports. Mine used sealing washers. Assuming the ports are flat there’s no reason you couldn’t use those. You could try using o-rings but no telling how long they’d last. I wouldn’t want fuel leaking into the boot.

Just changed out my SU Fuel Pump on Series 2 on the side of the highway last month. The new pump did not come with sealing washers, but did have two black o-rings. No choice but to use the o-rings (on pump side of banjo fitting). The pump ports add an o-ring groove, and were not flat-faced. No leaks yet, but will go get the washers anyway.

On my pump, the inlet was on the bottom side and outlet was on top when looking at it after install. Same as the bad, old pump. I think there should be an arrow on the inlet/outlet to be sure.

Took at least two days for the points to keep ‘ticking’ without the help of a few small taps first thing before taking off in the mornings.

You that’s what I’m remembering. It looks like even the original pump ports were milled for an o-ring if you chose to use it.