Fuel pump pressure regulator

[Olgawld]

Hi. Recently bought a 93 xflow Supersprint in need of some tlc. It has a facet fuel pump near the tank which I can just make out is a cube shape and had a red sticker saying facet then looks like 57AA. Car doesn't have a pressure regulator though which I thought was needed with these. Car seems to run ok. Do I need one and if so what do I need and where does it go? Thanks for any help.

[Jonathan Kay]

Does it have a part number stamped on one of the mounting feet?

How Facet part numbers work. (But this is a website with which I'm not familiar... )

Jonathan

[philwaters]

Yes, you should really run a pressure regulator when you use an electric fuel pump on a carb car to prevent the pump over coming the float valve and over-filling the chamber. You can use something like this: https://www.merlinmotorsport.co.uk/p/sytec-pro-fuel-pressure-regulator-10mm-pf-reg-6

It just needs to go in the fuel supply pipe from the pump, before the carbs. The scales are a bit of a guess, but you should be okay setting it at around 3 or 3.5 to begin with.

[Olgawld]

Thanks for the replies. I'm away at the moment so can't look till the weekend but I don't remember seeing any other numbers on it. I'll look into getting one then because I was pretty sure it should have one. Thanks

[patibbitts]

The Facet type pumps come in various pressure types - the ones recommended for twin carb set up are usually regulated to supply fuel at low pressure - max 2.5psi.

 

The ones for injection cars are much higher pressure (as expected).

 

My Lotus Twincam engine has a low pressure Facet pump fitted without a regulator and works just fine, although I purchased it and know it's origin and specification.

The use of a regulator guarantees the pressure if you are unsure about the pump, however, it may be wise to just buy a new low pressure pump as the regulators are about the same price now days.

The newer, Round Facet pumps can be purchased to your required spec and are reasonably priced - also self priming, will lift about 300mm above the tank and not quite as noisy as the square brick Facet type.

Beware of cheap £12 far eastern copies they fail when you least want them to!

[Olgawld]

Just had a look and there's a cube shaped facet pump on eBay, which looks the same as mine, which says it's regulated to 2-4 psi pressure. So maybe if that's the one fitted I don't need a regulator. Does seem to be running ok without one.

[DaveMorris]

I believe that you don't need a regulator with these "cube" pumps (for reasons stated above).

I have one as surplus in the garage if you would like it (I increased power above that which the pump could reliably meet fuel flow demands). PM me your address if you do,

Dave.

[bjw]

Facet 'cube' pumps range from 1psi to 15psi and they all look the same, so unless you've found the number stamped into the mounting flange nothing is certain, but if you aren't having problems why worry?

My pump has '40105' stamped on the flange which indicates it's a 3-4.5 psi unit. That's the correct one as specified by Caterham and the date code (notched into the top label) shows it's the original fitted in 1998 - working with twin DCOEs for over twenty years with no additional regulator.

Cheers

[DaveMorris]

Confirm. Mine's a 40105 . . .40 on one side of the mounting hole, 105 on the other. D