B&B fuel gauge erratic

pazcarguy · #1 (**permalink**) 04-06-2009, 09:14 AM

I just got my B&B on the road and the fuel gauge is very erratic. I filled the car up to 3/4 tank and while driving, the needle bouces continually from 1/4 to 3/4 until you stop, when it settles out. This was purchased as a turnkey minus from B&B so I did not put the sender in. Does anyone have any suggestions how to fix? Brian from PA.

strictlypersonl · #2 (**permalink**) 04-06-2009, 11:00 AM

Check that the sender and/or tank is properly grounded. Hopefully this is not due to a lack of internal tank baffling.

GreenSnakeDoc · #3 (**permalink**) 04-16-2009, 01:06 PM

I've got the same waving needle problem with my LAX (now B&B). LAX built the car using a Ford gas tank and sender. The sender was not compatible resistance wise with the Stewart Warned fuel gage. When the gage read 3/4ths full, the tank was near empty. I bough a "universal" S&W sender on ebay and its resistance values allow the fuel gage to read properly. This was not an easy install as I had to graft the S&W float and rheostat to the stock Ford pickup tube and seal plate. The gage now reads "true"; however, when driving, accelerating, braking and turning, the fuel in the tank sloshes back and forth causing the float to go up and down making the needle wave. Go to ffcobra.com and search for "slosh". This situation is expalined in great detail, and one electical wizard develped an anti-slosh circuit to prevent needle waving. It seems to have been a common problem with some Mustang tanks that were not internally baffled to the extent that many Mustangs had a factory anti-slosh circuit built into their dash.

jams · #4 (**permalink**) 04-16-2009, 02:12 PM

Do a search on the B & B forum. This was discussed quite a bit. I tried a bunch of things with little success. Now I just ignore the bouncing needle.

The sender is garbage, if you find a better one with the same resistance it will work much better.

Ronbo · #5 (**permalink**) 04-16-2009, 04:40 PM

Put an electrolytic capacitor from the sensor lead on the gauge to ground. 50volt / 100uf should do it. you can go to a 220uf or 470uf if you want a greater lag. (uf stands for microfarad) You can even go bigger if you want like a 2200uf, depends on the resistance of the sender.

The capacitor is polarity sensitive so + goes to the sensor terminal. Radio shack should have these.

http://www.radioshack.com/product/in...ductId=2102506

Karen Wells · #6 (**permalink**) 07-08-2009, 12:59 PM

he gauges B&B used was from T.G. Faria, they are Marine gauges.You may be able to call them up and order a new one. And not go to B&B Mfg.
Sometimes you can bend the steel in the sender in the fuel tank to go up right.
The senders are cheezzz and you can call B&B Mfg. and get another sender to replace.

mickmate · #7 (**permalink**) 07-08-2009, 04:09 PM

Guages are usually 33-240 ohm or 0-90 ohm. Make sure your sender matches your guage. Tanks should be baffled and if it's a float type sender with no baffles it will slosh constantly unless the car is sitting still. They are no fun sitting still so find out what your guage needs for a sender value and put in an inductive tube type sender instead of a float and lever type. Peter at Nisonger has them and they are also available from Centroid.