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'74 MGB Voltage Stabiliser (with Question)

To: british-cars@triumph.cs.utah.edu
Subject: '74 MGB Voltage Stabiliser (with Question)
From: todd@mudbug.nrlssc.navy.mil (Todd Mullins)
Date: Thu, 1 Sep 1994 16:36:42 +0600
...and all this time I thought my motor was running hot!  Boy am I relieved.

Temperature gauge has been reading _very_ high since I got the car.  Of course
this worried me, so I replaced the thermostat, recored the radiator, replaced
the gauge sending unit, and generally checked around for leaks and such.
The gauge still read high.  I pulled the thermostat out.  No change.  The
coolant drain plug on the block is clogged, even after sticking a screwdriver
into it, so I thought, "Great.  I've got a clogged block.  I'm going to have
to tear the motor down to clean it out."

While fishing around under the dash, I noticed this thingy hanging from two
wires.  Of course I looked at it, but I figured that since the wires were
still connected, it was probably OK.  Well, after studying the Haynes manual,
I discover that the thingy is called a "voltage stabiliser", and it controls
the voltage to the temp gauge and the fuel gauge (which is dead, BTW).  After
studying the wiring diagrams, I notice that the thingy is supposed to be
_grounded_, presumably by having it mounted to the unibody with a sheetmetal
screw. (BTW, the wiring diagram for the '73/'74 in the "Glovebox Owner's
Workshop Manual", a green bookie I got from Moss, incorrectly omits the ground
connection for the thingy.)

"Okay," thunk I, "I can handle that."  I found a suitable place to mount the
thingy (a bracket for some wiring), complete with grounded sheetmetal screw.
And whaddaya know, the gauge now reads on the cold side of "N"!  I'll be
putting the regular thermostat in this evening.

Question:  the Haynes manual says "If the voltage stabiliser is faulty it must
be renewed with the B and E terminals uppermost and not more than 20 degrees
from vertical."  What does this mean?  I have no idea where it was originally
mounted; can any '74 'B owners take a (contorted) glance and tell me?

Moral of the story:  Don't automatically trust your gauges.  An apparently
major problem could simply be a broken connection (yahoo!!).

I'm a happy dude...

-todd
todd@mudbug.nrlssc.navy.mil     On the lovely Mississippi (USA) Gulf Coast

P.S.  "JWIsland", this is my sole transportation (I could take wifey's car
      in a very big pinch) on my 50-miles-round-trip commute.  After fixing
      a few kooky bits, it's been extremely reliable.  Of course, Mum took
      awfully good care of it for all those years.

'74 MGB              102K mi
'84 VW Rabbit Diesel 176K mi (broken timing belt; immobile)
'84 Volvo 245GL      177K mi
'85 Nishiki Prestige custom  (not ridden these days; make an offer)

"People said it because other people said it.  They did not know why it
was being said and heard everywhere.  They did not give or ask for
reasons."
                      - Ayn Rand, from _Atlas Shrugged_


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