In a message dated 1/12/98 1:21:48 PM Eastern Standard Time, peterz@merak.com
writes:
> > All this is shown on the schematic for the '75 (the '76 schematic is
> > in error around this relay, and can't be relied on).
> >
> Dan, in my Bentley manual, I have a schematic labeled 75-76. There is no
> separate one for the two years. What is your source for schematics? I
> would be interested in getting a separate one for the two years (my car
> is a 76).
Peter,
Who knows what's correct for a Triumph? I don't think even Triumph knew for
sure.
The best source of schematics that I have, believe it or not, is a catalog put
out by the Roadster Factory a few years ago. In the back of the catalog, they
reprinted copies of the schematics from the appropriate year's owner's manual.
The schematic on page 17 of the Bentley manual, labeled '75 - '76, is the same
as the schematic for the '76 as shown in the TRF catalog.
If you look at the starter relay, you will see that it is just hanging there,
doing nothing. You will also note that, although the starter will work with
this configuration, the ballast resistor is not bypassed while starting. If
you'll look at the white/yellow wire from the coil, you will see that it
somehow becomes pink/white, before it joins the other white wires connected to
the ignition switch.
The pink/white wire is the ballast resistor. On previous years, the
white/yellow wire ran to the relay, with the ballast wire connecting to it at
midpoint. The relay connected the w/y wire to a brown wire when the starter
was operating, bypassing the ballast.
I have not been able to confirm the details, but I believe the end of the w/y
wire that used to go to the relay now goes to the extra terminal on the
starter. If you look at the diagram, you will see an extra terminal just below
the terminal with the w/r wire. This terminal appears on many Lucas starters,
and is energized when the solenoid is energized. By connecting the w/y yellow
wire here, it applies a full 12 volts to the coil when cranking. I assume the
relay is eliminated, but I am not sure. If any one knows the details of this,
I sure would appreciate hearing from you.
Somewhere, I came up with the idea that the OD relay was eliminated and the OD
wired directly from the switch when they added the ballast resistor, and the
relay was then used for the resister bypass function. At one time, I had the
wiring diagrams and color codes for this, and I think I still do, but I can't
put my hands on them right now. If they eliminated the starter relay function
in '76, I don't know if the relay went back to the OD, or was just eliminated.
The '75 schematic is identical to the '74, except the seat belt interlock has
been bypassed. The schematic for the '74, btw, is NOT like the one shown as
'72 - '74 in the Bentley. I woud not bet money on any schematic being correct,
but the few times I have been able to make a comparison, the owner's manuals
have been the most correct.
Dan Masters,
Alcoa, TN
'71 TR6---------3000mile/year driver, fully restored
'71 TR6---------undergoing full restoration and Ford 5.0 V8 insertion - see:
http://www.sky.net/~boballen/mg/Masters/
'74 MGBGT---3000mile/year driver, original condition, slated for a V8 soon!
'68 MGBGT---organ donor for the '74
|