Fuel pump with carbs, Should it run all the time? Options

[brooks944]

Hi, I have a 1.8 ( now 1911) with 40 Webers and Web cam. It has run rich and my local shop has changed jets and it was running strong. I am now having starting problems and it seems to smell like it’s rich again. Last time I drove it it backfired a couple of times under load and it sounded like the backfire was from the carbs(?). My main question is on the fuel pump, which is a faucet type from the local auto parts store. Should the pump run continuously or shut off when a certain pressure is reached? Mine runs all the time when the key is on. I don’t believe there is a fuel pressure regulator on now.
Thanks for your help on my issues,
Rick

[moto914]

My 914 that has carbs , has the same setup but with Dellorto carbs. The fuel pump sounds less audible when under pressure but not completely silent. One of my carbs needs a rebuild.

[930cabman]

Fuel pressure must be less than 3 psi, also fuel levels must not be too high. Carbs can be a bit fussy, but once dialed in will run for years

[GregAmy]

Pump runs all the time.

You want a fuel pressure regulator.

[brooks944]

Thanks for the replies. What fuel pressure regulator would you recommend? Also where should it be placed, after the pump and before the filter or other?

[technicalninja]

Every square Faucet style I've installed REQUIRED isolation mounts.

Like this

https://www.jwwinco.com/en-us/products/3.4-...AyABEgJR2_D_BwE

You need to provide a ground strap if the pump is single wire.
I always ground the case anyways.

Without something like that that pump drives me crazy!

It's a short drive...
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[Osnabruck914]

Get a low pressure rotary type pump. You will be much happier. Take that facet pump and use it as a paper weight.

Osnabruck914

[Front yard mechanic]

the fuel return line will help quiet it down some. Plumb it after the carbs. If you keep it on jack stands with the battery out it’s real quiet

[SirAndy]

the fuel return line will help quiet it down some. Plumb it after the carbs.

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Utilizing the stock return line has many upsides and no downsides.
Keeps the fuel cooler and prevents boiling from heat-soak.

Get a low pressure rotary type pump. You will be much happier. Take that facet pump and use it as a paper weight.

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This is the pump i had on my 2056:
https://www.cbperformance.com/product-p/319...e7z9AA76ZhCfxII

Quiet with a filter and built-in regulator.
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[technicalninja]

I have another use for the Facet...

the ONLY one I currently own has 6+ feet of fuel hose on either side and battery post sized alligator clips on a long pigtail.

I use the crap out of it as a transfer pump.

[brooks944]

Thanks everyone for replies. On the CB Performance pump in the attachment of one reply, it says it runs at 3.5 psi, which another commenter said was to high (wrote it needs to be lass than 3). Is the extra 0.5 psi a concern?
Thanks!

[rhodyguy]

Facet pumps are dandy for emptying fuel tanks and not taking a gas shower. You need a adj fuel pressure regulator when using one with carbs. And you will need a quality FP gauge. Lay in a supply of shouldered clamps while shopping. Not cheap ass slotted screw clamps.

[porschetub]

Thanks everyone for replies. On the CB Performance pump in the attachment of one reply, it says it runs at 3.5 psi, which another commenter said was to high (wrote it needs to be lass than 3). Is the extra 0.5 psi a concern?
Thanks!

Yes could well be a concern, @ that pressure you could still be overwhelming the float valves ,I run the CB pump but still have a regulator and gauge ,I tested mine before adjusting down and it was just over 3.5lbs ,had to go down to 3 psi to suit my carbs as it was the sweet spot ,haven't changed that since.
The silver Holley regulator 1 - 4 psi ( part number 12-804 ) is ideal in this application and a good well proven unit , just make sure you choose a quality brand fuel specific gauge ,I got a mr gasket one from summit racing .
I notice that some folks run 2.5 psi with IDF Webers and have no issues but personally have no experience with those carbs as I run Dellorto's .
Cheers.

[930cabman]

Thanks everyone for replies. On the CB Performance pump in the attachment of one reply, it says it runs at 3.5 psi, which another commenter said was to high (wrote it needs to be lass than 3). Is the extra 0.5 psi a concern?
Thanks!

Yes could well be a concern, @ that pressure you could still be overwhelming the float valves ,I run the CB pump but still have a regulator and gauge ,I tested mine before adjusting down and it was just over 3.5lbs ,had to go down to 3 psi to suit my carbs as it was the sweet spot ,haven't changed that since.
The silver Holley regulator 1 - 4 psi ( part number 12-804 ) is ideal in this application and a good well proven unit , just make sure you choose a quality brand fuel specific gauge ,I got a mr gasket one from summit racing .
I notice that some folks run 2.5 psi with IDF Webers and have no issues but personally have no experience with those carbs as I run Dellorto's .
Cheers.

I have ran 2 - 3 psi with my twin Webers for decades, never ran out of fuel, ever. This is one place where less is more

[rfinegan]

Yes, the fuel pump will run off the ignition switch power. I have seen clever set ups with relay and an oil pressure switch. So the fuel pump will only run when the engine is running. Both power supplies have been used with no ill effects

[brooks944]

Thanks all. Porschetub, I ordered the one you recommended. Do you have a picture where you mounted yours?

[mlindner]

Thanks all. Porschetub, I ordered the one you recommended. Do you have a picture where you mounted yours?

Most by the steering rack or under the tank. I put mine more up front for easy access under a modified fuel tank. Should be in the push position. Best, mark

[porschetub]

Thanks all. Porschetub, I ordered the one you recommended. Do you have a picture where you mounted yours?

Mounting of the regulator or the pump ?.
My pump is mounted to my alloy suspension cross member and protected by the under tray , my regulator is mounted to the rear engine bulkhead up high so I can read the gauge .
I researched this setup and found it was the most common used ,IMO the best way to go ,cheers ,sorry can't find any pics ,it was a long time ago.

[brooks944]

Thanks all for responses. Does anyone have pictures of where they located the regulator? I got the Holley one that was recommended with the gauge, and now request your input on where to locate. porschetub had his on the rear engine bulkhead, anyone else have their’s there and some pics or other recommended locations?
Again, thanks for everyone’s help.
Rick

[brooks944]

Also where should the gauge be located? The FPR has one line in and 2 out to the carbs, will it matter where it’s located after the FPR?
Thanks again guys!