• Hi Guest! Being a Paying Supporter is NOT a requirement to participate at BCF. However, subscribing will help ensure we can continue to serve the LBC community for years to come. If you enjoy BCF and find our forum a useful resource...Please consider supporting us by **Upgrading**
    (PS: Subscribers don't see this banner)

Fuel gauge and sender unit for BJ8

Lutz Kramer

Senior Member
Country flag
I had a fuel quantity indication that was sometimes confusing or better to say more or less working correctly. Since I have already repaired the sender unit a couple of times by shortening and soldering the tiny wire of the coil, I decided to give up with the original unit and bought a replacement here in Germany.

The unit works, but the other way around like it should. I have a BJ8 and when I raise the float the resistance drops which leads to an indication close to “(E)mpty”. Now the guy responsible for spare parts told me that I might have a fuel gauge of a BJ7 that works just the other way around like the one for a BJ8.

Is he right?
Last edited by a moderator:


Darth Vader
Re: Fual gauge BJ8 and sender unit

Hi All,

The sending unit and the orientation of the float has been a point of confusion for quite a while. First, many (including me) would not have recognized that there are 2 sending units (unless purchasing a new one) with opposite resistance profiles. As I see it, the sending units are alike, except in the fixed direction of the float wire attachment. When comparing both units, Keep in mind that the dash gauge wire fixing stud (green line to the dash gauge) is located at the end of the internal coil that provides least resistance. Therefore, on earlier models (BJ7 and earlier), the stud will be positioned toward the Rear of the CAR with the float oriented in the opposite direction. However, on BJ8s (Phase 1 & 2), the stud and the float will be oriented to the same end, facing the Front of the CAR.

A short while back, Steve Gerow provided these drawing to explain the correct positioning of the float, with respect to the fuel tank, providing float spacing for registering Empty. Please note, with respect to the sender, Steve has presented a Pre-BJ8 sending unit, however all sending units should have their floats positioned toward the Front of the Car (as I understand all 6 cylinder models share the same fuel tank profile).

As an aside, I wonder if by repositioning the float wire support through the opposite side of the rotating peg, an early sender could be converted into a late?

Similar threads
Thread starter Title Forum Replies Date
J Fuel sender, fuel gauge 100 4 Austin Healey 6
H TR2/3/3A Fuel sender or gauge? Triumph 8
T Fuel Gauge & Sender Unit Austin Healey 5
newmexTR3 fuel gauge/sender wiring Triumph 7
NutmegCT TR2/3/3A fuel gauge / sender TR3A Triumph 25
jhorton3 Fuel Gauge Sender Spridgets 4
L Fuel sender specs... inaccurate gauge?? Spridgets 4
Boink Early Mini Fuel Gauge - adjusting it British Motor Corp 0
S WANTED: Healey BN1 "Smiths" Fuel Gauge (Dead or Alive) Austin Healey Classifieds 3
R TR2/3/3A Fuel Gauge Triumph 19
T Wanted Smiths fuel gauge for Mk 1 Bugeye Sprite [FG2530/31] Spridgets Classified 1
S Fuel gauge calibration procedure Austin Healey 18
C MGA Fuel gauge question MG 7
S Wanted 1959 Bugeye Fuel Gauge Austin Healey Classifieds 0
K TR4/4A Voltage Stabalizer and Fuel Gauge Readings Triumph 5
K TR2/3/3A Fuel gauge readings? Triumph 12
K TR4/4A TR4 Fuel Gauge'"light bulb socket" type? Triumph 11
B For Sale MGA JAeger Fuel Gauge, Dual Safety Gauge, Speedometer and Tachometer MG Classifieds 0
B For Sale Austin Healey 100 Smiths Fuel Gauge, Dual Safety Gauge, Speedometer and Tachometer Austin Healey Classifieds 0
B For Sale Triumph Tr3 Fuel gauge Temp gauge Oil pressure gauge, speedometer tachometer Triumph Classifieds 0
K TR2/3/3A Re TR4 and TR3 fuel gauge sending units again.... Triumph 0
K TR2/3/3A Can a TR4A Fuel Gauge be swapped into a TR3A? Triumph 8
K TR2/3/3A Fuel Gauge again.... Triumph 11
N Fuel gauge problems? Spridgets 9
warwick-steve Fuel Gauge always shows 1/4 full Austin Healey 27
N Fuel gauge problem's? Spridgets 4
D Wanted TR3A Fuel gauge Triumph Classifieds 4
T TR2/3/3A Why is voltage stabilizer not needed for TR3 fuel gauge? Triumph 4
Tim Hollister Wanted Need Fuel Gauge for 1959 Bugeye Spridgets Classified 2
George Zeck Looking for a fuel gauge ...... Spridgets 2
S Fuel Gauge Question Austin Healey 8
K For Sale TR3 Fuel Gauge Triumph Classifieds 8
warwick-steve Fuel Gauge always indicates 1/4 full. Austin Healey 13
George Zeck What fuel gauge SHOULD I have? Spridgets 3
sim 1958 fuel gauge sprite Spridgets 11
N Spitfire Fuel gauge Triumph 8
Martinld123 Austin Healey 100 BN2 fuel gauge not working Austin Healey 13
N Fuel gauge question?? Spridgets 3
B TR2/3/3A Fuel gauge problem Triumph 7
F Running out of fuel - gauge problem? Austin Healey 5
K TR2/3/3A TR6 fuel gauge in a TR3? Triumph 1
K TR2/3/3A Fuel gauge and switching to Neg ground? Triumph 2
K TR2/3/3A Can a TR4A fuel gauge be used in a 3A? Triumph 8
toysrrus TR2/3/3A How to test fuel gauge & sending unit? Triumph 10
Rut Bugeye fuel gauge Spridgets 14
Editor_Reid Fuel Gauge for 1967 Sprite Spridgets 4
M TR4/4A Temperature and Fuel Gauge Wiring...Help Wanted Please Triumph 6
C TR6 Fuel gauge mystery Triumph 6
A Fuel Gauge - Help Needed Austin Healey 18
N Correct Bulb Holder for BT7 fuel gauge ? Austin Healey 4

Similar threads