fuel system concerns

I have a Barry Grant 400 pump, as well as a Barry Grant filter and regulator. Bought them new, been sitting in garage for years till new motor was ready. Now that there in use, I put a new fuel pressure gauge on regulator and needle rapidly jumps from 4 to 9. Can't really tell when it's adjusted. I thought the gauge was bad, but I am wondering if regulator or pump is causing needle bounce. Has anyone had this issue?

70 views and not one opinion

The pump has its own bypass, and then you can set a second pressure regulator. Where are you seeing the pressure change? On the pump itself or after a dedicated pre-carb regulator. The pump gauge and regulator is cheap and basic and lets you dial back some pressure from the system. Ive run the pump with no bypass and as low as 20 psi, not much different, dead headed with no bypass it builds heat fast and looses performance if there is not free flow on the extreme end of the system. The BG pump is an antique in design and build quality. Mine have been rewound and brushes and springs changed twice, they eat shaft seals..... my advice, buy something better soon.

I agree with Kim. And if you go shopping, shop MagnaFuel, IMO.

Throw the BG stuff in the trash and go Magnafuel.....

Been there. A BG reg I bought lasted all of about 15 mins. I'd be sus on the reg to be jumping that much. Check what the pump,is set at first , likely around 20 psi.

Magnafuel pump and reg I changed to is 8 yrs old now

With a gauge on the pump the lowest I can get the pressure down to is 22 psi. I have cut spring, no help. Ran bypass in bucket thinking maybe line was restricted, no help. Any body have any ideals ?

What size fuel line are you running ? ...I still run a BG280 on my street/strip setup with a step down box, it supports a pretty stout Cleveland and 2-stages of nitrous, but the system has 2-regulators, and a bypass line running past the carb feeds to a bypass regulator running back to the cell. The 400 will build heat very fast and does not like to be stepped down why I changed to the 280 (non issue for drag only), the flow numbers / pressure will increase if you are less than 10-12AN with 5/8 line. It is a complete fuel system which you can make work, but if the sum of the parts don't add up upgrade to newer technology.

Every thing is size by BG spec.

Is it running or dead heading when observing the gauge?

Motor not running. Will run, but trying to get pressure down first.

sg86coupe wrote:With a gauge on the pump the lowest I can get the pressure down to is 22 psi. I have cut spring, no help. Ran bypass in bucket thinking maybe line was restricted, no help. Any body have any ideals ?

That shouldn't matter . The Magnafuels come set at 28 psi . I just did a Product Engineering pump and set @ 20 . The reg should be able to control the pressuer down where you want , around 6 psi ??
I'm assuming you are trying to set the bypass pressure first ???

Yes Sir, engine builder said 17 at pump and 7 at regulator