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MGB voltage regulator

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Sopwith_Camel

Sopwith_Camel

Jedi Knight
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ok my dash just went off, so the fuel gauge and temp stoped working , i was trying to ge the tach working but this is now the priorty.
is it the Voltage Regulator and how do i test that?
I put the multi meter on the Voltage Regulator and it dose not beep but on the rusty one i pulled out of my tool bag it dose which one is good?
it dosent seem to be the ground?
 
First thing to check is the fuse. You might have shorted something while working on other things. Good idea to disconnect the battery when working on anything electrical.

If the fuse is OK, there probably is a loose wire somewhere. Probably not a bad regulator itself, but there may be a bad connection to it. To check the regulator itself, disconnect the wires to the A1 and A terminals and check for continuity between those terminals. If you have continuity, the regulator is not the problem.
 
yeah i just tried it in the GT it worked ok. so i guess im chacing a ground issue since it is the fuel, temp, and oil. fresh wire from the fuse
 
What year is the B? Ours is a 1980 and the gauges get power from the second fuse from the bottom. The fuse gets power from the relay in front of the fuse block with the ignition on.
 
this is the 68, the wireing harness is a compete mess.
i have checked the fuses, i have a fresh wire running from the fuse box to the voltage regulator.
the voltage regulater is new with a chip , but it worked when i put it in the GT.
the dash is bolted on tight so that should be grounding.
i have a ground going from the back of each gauge can.
 
ok i have checked the wire from the ignition to the fuse box, from the fusebox too the voltage regulator.
i have check and tryed a different voltage regulator i have swapped in a new wire from the voltage regulator to the fuel gauge and checked the ground and i ve checked the ground of the can to the bolt that holds down the windscreen.

im out of ideas.
 
yep , i forget that the chemo damaged my eye sight.
yep big mg rally next week.
steve
 
Fuses often break internally where they attach to the cap(s) on the end. A visual check is insufficient in these cases so it's best to check with a meter. Also I think you were referring to the voltage stabilizer. The regulator is part of the alternator on later cars. On early positive ground cars there was a voltage regulator mounted on the rh side of the engine bay and the voltage stabilizer was under the dash. It was supplied with 12v and output is 10v to the fuel gauge. 12v negative cars had the temp gauge added to the stabilizer when the temp gauge went electric.
 
There's a "double whammy" with the fuses and fuse block in the system. As Ben notes, the glass fuses can have an end cap disconnect from the strip in the visible part of the glass tube and look just fine. An ohm meter will reveal that. Another potential issue is the clips or their rivets corroding and losing continuity. Usually a cleaning of the clips with a fine abrasive like #600 wet-or-dry can fix that. If it's the rivets, best solution is a replacement fuse block.
 
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