Facet silver top fuel pump - fuel pipe alterations

[smudger]

Hi folks,
After fitting a Facet cube pump under the bonnet in emergency, I have decided to convert more permanently to a Facet Silver Top Road cylinder pump under the rear of the base unit in a similar style to NADA pumps as has been covered on here before.
What I can't decide on is the re-routing of the fuel pipes immediately before the pump. I was going to do away with the reserve tap from the car altogether and just have one pipe running from pump to carbs. I have used the reserve tap twice in anger in 23 years and wouldn't miss it. Clearly the pump would have to be fed from the current reserve pipe.
That would leave the current main pipe redundant and requiring a solution.
It could either be cut and blanked off near the tank - but I will always worry about it leaking - I hate petrol pipe projects to be honest but needs must.
Or, has anyone tried - would it even work - feeding both existing fuel outlets via a T-piece into one pipe before the new pump? The new pump would then draw fuel from both existing pipes. Are there any problems with that set-up? I can't see why there should be but those with better knowledge of the way pumps and fuel lines work might be able to say. A possible advantage would be if one pipe got crud in it the other one would still flow.
Also, I have never actually heard a Facet cylinder pump in operation. Do they click away constantly and annoyingly like the cubes?
Cheers, Smudger.

 

[harveyp6]

Or, has anyone tried - would it even work - feeding both existing fuel outlets via a T-piece into one pipe before the new pump? The new pump would then draw fuel from both existing pipes. Are there any problems with that set-up?

It will draw air as soon as the level drops below the main supply feed in the tank, so if you're prepared to lose the extra reserve capacity it will work, if you want to use the full capacity of the tank you won't be able to.

 

[smudger]

In the immortal words of Capt. Mainwaring, I just wondered who'd be the first to spot that. Of course it would draw air, what was I thinking? Not much obviously. To blank it off under the car with an end cap of some sort is the only practical solution then to keep the full capacity of the tank.

 

[mrtask]

The Facet pump will indeed tick away constantly, and even if you have it shrouded with the foam sound insulation they used on the NADA cars you'll hear it from inside and outside the car. I just got used to it!

 

[Quagmire]

I'd disagree with Mr Task on the noise - I can hear my Facet when the ignition is on but engine off, however I can't hear it at all with the engine running. Its mounted in the NADA position at the rear, feeding the swirl pot for my EFI pump. Its mounted on rubber bobbins, but not shrouded at all.

 

[smudger]

An alternative to a Facet would be a SU AZX1307. They were used on the MGB V8 so are clearly suitable for the installation and no fear of a pressure regulator possibly being needed. I also seem to remember from dim and distant ownership of a Series 1 XJ6, which also used them, that they weren't noisy at all when running although they were in the boot, not under the car.

 

[V8P6B]

I was thinking of fitting a facet pump at the rear on the reserve line. I had some kind of plan to retain the mechanical pump, and switch to the electric if vapour lock occurred. I was wondering that, as I assume there is a switch on the choke cable to activate the choke warning circuit, maybe I could fit the same kind of switch to the reserve tap cable, wire it to a relay, so that if vapour lock started to occur, pulling the reserve tap would both switch to the reserve line and start the electric pump in one swift action. Haven't got past the planning stage yet, but as my car does seem particularly predisposed to vapour lock in traffic jams & hot weather, and not wanting to be stranded in the queues outside Silverstone Classic again in July, I may have to get my finger out...

 

[smudger]

That sounds like a good idea in principle and a nice bit of inventive engineering, if you can rely on the choke operated switch to stay on or off as required. On several of the P6s I've had I remember being able to get the choke light on or off, i.e. turn the switch on or off, just by knocking the choke slightly sideways or up or down. That wouldn't be much use if you were using the switch to operate a relay. The same happens on my current car. Push the choke fully home, choke light goes out - turn choke knob slightly clockwise, choke light comes on.
I have now mounted my engine bay Facet cube on some rubber mounts which has quietened it a lot compared to before, probably enough to put me off crawling under the back of the base unit with a replacement Facet cylinder pump.