enlightened engagement

HMM GARAGE
58 restoration
Stewart Warner
Green Lines
64 Modified
Muscle
1970 Plymouth
’Cuda convertible
Enlightened
Engagement
and not purchased as a new kit, it took multiple trips to the auto
parts and hardware stores to get all that was needed and to try
out different ideas. A few times, I realized I needed a certain part
just when the moment came to install it. Keep this in mind if you
are trying to decide whether or not to install vintage gauges or a
new kit.
• Measure Twice, Cut and Crimp or Solder Once: Since every vehicle and situation is different,
there’s a lot of trial and error involved when doing a project like
this, so make sure you test fit everything to see how it will lay out,
and then determine whether or not it’s a safe and practical setup
before you start tightening things and finalizing the installation.
70 performance
Hydraulic
• Idiot’s De-light: For this application, it appeared to be
easy enough to retain the temperature warning lamp, since the
later intake manifold installed on this engine has an additional
port on the passenger side to access the coolant. (Read on to
learn how well that worked out.) The oil pressure sending unit
was a challenge, however, since a small manifold had to be built
from scratch using a tee and fittings that would accept and fit
the stock-type switch and the new oil line, in a confined area. It
worked, but it was time consuming.
• Tried and Failed: Since the water temp gauge was
going on the driver’s side (initially), I’d first hoped that the
large existing hole in the firewall for the factory speedometer
roller cams
Ray
74 Ask
Tech Q&A
by Ray Bohacz
78 Go-Fast
Goodies
New products for
your muscle car
Part 2: Installing Vintage Stewart Warner Green Line gauges
Words and photography by Thomas A. DeMauro
W
e discussed the
history, design, identification,
variations, date coding and tips
for buying vintage Stewart Warner
(“SW”) Custom Green Line gauges in the last issue,
HMM #142, June 2015, and we highlighted ones
that are currently available. For Part 2, we will
install a set under the dashboard of a 1967 Buick
GS 400. The period-correct gauges chosen for this
project were collected by the author and include a
21⁄16-inch voltmeter from the Deluxe line and 21⁄32 inch mechanical water temp and oil pressure from
the Utility line.
• Voltmeter: The voltmeter shows the condition of the battery when the engine is off (and the
key is “on”) and regulates voltage produced by the
alternator when the engine is running. The bimetallic heat-actuated voltmeter I used takes a little time
to warm up when the key is turned on, so don’t get
nervous — like I did — the first time you test it and it
doesn’t react right away.
• Mechanical oil pressure
gauge: This gauge employs a center-geared
Bourdon tube mechanism and reads oil pressure
directly from a port in the engine, so it doesn’t
require a sending unit. To connect it to the engine,
copper line was chosen over the nylon type. The
debate continues regarding which is more durable
and why. If feeding oil to the gauge in the cabin
of your car via nylon or copper tubing concerns
you, install a braided line — or consider an electric
gauge and sending unit.
• Mechanical Water Temp
Gauge: Also a Bourdon tube type, this gauge
employs capillary tubing with a bulb at the end
that is to be immersed in the coolant. The tubing
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1
cannot be removed from the gauge, and it should
not be sharply bent, which adds a bit of complexity to its installation.
Placement
As discussed in Part 1, placement is very important, as the gauges have to be easily visible while
driving. Centered under the dash is a traditional location, which places them fairly close to the driver,
but not so close as to be blocked by the steering
wheel. This project had an additional consideration, however: The line-of-sight to the optional
factory tach on the consolette would be blocked.
Thus, the gauges had to move more toward the
passenger side.
Since any gauge with a pointer is at least somewhat subject to parallax error, where the reading
appears to be different when viewed from sharp
angles, it was decided to put the voltmeter first
because its delineations are so close together and a
small change in needle position can be significant.
Given that there was plenty of line length available
for the oil pressure gauge, it could be positioned
anywhere in the panel, so it was placed in the center. The water temp gauge’s capillary tubing had to
reach the access port of the intake manifold. Since
the hole in the firewall was on the passenger side,
the position that was closest to it would provide for
the most available length, so it was placed in the
right-hand position of the panel.
Additional
Considerations
• “Yeah, it’s me again.”: Because
everything for this story was collected individually
The finished installation demonstrates a working voltmeter and oil
pressure and water temp gauges, and they don’t block the driver’s
line-of-sight to the existing tach. The voltmeter, from the Deluxe series,
uses a straight-edge-style pointer. Oil pressure and water temp gauges
are from the Utility line and feature arrow-style pointers. Notice the
voltmeter’s number font is slightly different from the other two.
4
This style of gauges uses lighting slots in the body, and they receive
light from a bulb mounted in the gauge panel. (New Stewart Warner
Green Line gauges [not shown] use a “chimney” to accept a lamp socket
for each gauge.)
5
Lighted Utility line
gauges only have
two slots at the
top instead of two
at the top and two
at the bottom like
Deluxe gauges.
The brass fitting
on the oil pressure
gauge came with
the copper line kit.
2
An NOS SW chrome panel (above) had to be sourced online when
I discovered that the panel that had come with a previous gauge
purchase was
dimpled from
overtightening
the gauge
bracket nuts
(right)—keep
that in mind
when installing
yours. The new
one cost $20
and still had the
3
clear film over
its face.
6
Here are the gauges pre-installed in the panel with their brackets and
electrical connections, since it won’t be possible to photograph them
well once in the cabin. The lamp wires only need to connect to the
12-volt instrument panel lighting circuit, since the panel is already
grounded via the metal dashboard. The red 18-AWG wire on the
voltmeter’s positive terminal will run to a 12-volt switched power source
at the fuse box, and the black 18-AWG wire on the negative terminal
goes to ground at one of the panel’s retaining screws.
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cable could be used to route the capillary tubing to the port
to install the bulb. The rationale was that it was on the driver’s
side already, was big enough to fit the bulb and fitting, and it
negated having to drill a new hole. The reality was that it was
too low and far to the left to allow for gentle bends in the tubing around other obstructions, and the bulb didn’t reach the
port on the intake.
• Order of Appearance: If you are drilling a hole
in the firewall to pass the water temp bulb and fitting through,
it will have to be at least 11⁄16-inch. You may decide to run the
oil pressure line through the same hole to avoid drilling two.
However, by drilling a slightly larger hole (1-inch worked for
us), you will be able to remove the temp gauge bulb should it
7
After disconnecting the car battery, the installation began with the
panel. The gauges were removed to gain access to the mounting screws.
Relieving the area around the mounting holes in the lower dash of a little
paint aided in grounding the panel. An ashtray screw and one of the
glove compartment screws had the correct spread to match two of the
panel mounting holes.
eventually fail, without the additional headache of having to
remove the oil line first to gain clearance.
• Conceal and Protect: Vacuum hose was added
over the copper oil line. It not only protects it from abrasions
along its routing, it also makes it nearly invisible under the hood.
• Capillaries and Copper: Routing both lines
for this project took patience and care. The capillary tubing for
the water temp gauge is a bit stiff (remember it’s also old) and
not very easy to maneuver around the engine compartment.
The copper tubing for the oil pressure line bends very easily,
but it must be done carefully to avoid over stressing or kinking it. When all was said and done, purely from an installation
standpoint, electric gauges would be easier. But then there’s
Once the pipe plug
was removed on the
driver’s side, it became
apparent that my plan
was flawed. The hole in
the intake wasn’t deep
enough for the bulb to
fit, so it would have to
replace the stock temp
sending unit on the
passenger’s side—at
least until I come up
with a group of fittings
to make it work.
8
To keep it inconspicuous, the capillary tubing
was run along the
passenger-side rocker
cover, adjacent to the
stock wiring harness.
With a light application
of TFE paste on the
threads, the adapter,
bulb and fitting were
installed in the front
passenger-side of the
intake manifold.
Since it cannot be removed, the water temp gauge’s bulb and capillary
tubing were fed through its hole in the panel. They were routed through
a 1-inch hole in the passenger’s-side firewall that already existed—
possibly from a gauge
installation of a previous
owner—so another hole
didn’t have to be drilled. The
water temp gauge was then
secured to the panel.
9
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any of these methods are acceptable for installing its gauges.
• Tap in or tap out: Unfortunately, the 1967 fuse box
doesn’t have an extra ignition terminal or gauge lamp terminal
like many later ones do. To power the SW gauge lamps and
the SW voltmeter, their positive feeds will have to be spliced
into the existing 12-volt (switched on with the ignition key) and
gauge lamp wiring.
If you want to avoid tapping into the wires, you can access
the circuits at the fuse box via a fuse tap, which is a small piece
of bent metal that wraps around the end of the fuse and has a
spade terminal to accept a female connector.
Another method is to use a Posi-Tap (www.posi-products.
com), which splices wires without damage to the source wire
After some searching, these are the parts that worked best: NPT 1/4inch brass pipe tee (center); NPT 1/4-inch brass hex nipple (right); stock
oil pressure switch (left); adapter and fitting from the line kit (top). Note
that the hex will accept a 9/16-inch wrench on the nipple and that the
tee has square cut edges and a
lug on the end that will accept an
16
11/16-inch open-end wrench to
install it. It’s common to find both
parts that just look like threaded
pipes with no wrench lugs. Don’t
buy those, as they will be very
difficult to install and remove.
13
10
11
The early 1970s Buick intake
manifold has threaded
access to the coolant
passage on the driver’s and
passenger’s sides, unlike
the ’67. Therefore, the
warning lamp, its wiring
and its coolant temp switch
could remain active and in
the stock location—or so I
first thought.
the added cost of sending units, and in the case of using vintage
gauges, finding and ensuring that they are the correct ones.
• Confounding Compound: Some opinions hold
that the fittings don’t need any kind of lubricant or sealant for a
leak-free installation, others say it’s a must. I asked Mechanical
Engineer Robert Viscosi of Maximatecc, Stewart Warner’s parent
company. SW does recommend using Teflon tape or a similar
product in moderation on the male threads of any NPT fitting. I
used pipe thread compound TFE (Teflon in it) paste.
• Crimped or Soldered: Should wiring terminals
and connectors be of the insulated crimp-type or uninsulated
crimp-type protected with heat shrink tubing, or should the wires
be soldered and protected with heat shrink tubing? SW says that
The line was carefully uncoiled and vacuum hose was placed over it.
Then it was fed down the front of the engine and along the passengerside top of the engine and through the hole in the firewall. The zip ties
and insulated clamp (actually added after the line was secured at both
ends) were installed slightly loose for some flexibility to compensate for
engine movement while still keeping the wiring harness, capillary tube
for the temp gauge and the vacuum-hose-covered oil line in place.
14
If I was using another oil gallery access
port unrelated to the existing oil pressure
switch, or simply replacing it with the
gauge, the installation is as simple as
removing the old unit, installing the adapter
and engine fitting, sliding the hex nut
onto the line, followed by the ferule and
attaching the line as shown.
17
Once the line was connected to the port on the engine, the other end of
the copper line, already fed through the firewall, was cut to the proper
length. The hex nut was slid onto it, followed by the ferule. The gauge
was installed in the panel, and the line was attached to its adapter and
tightened with a 3/8-inch wrench.
12
A copper line for the mechanical oil pressure gauge was employed, and
it came with the required brass adapters and fittings for the engine
block and the back of the gauge.
Retaining the factory warning
lamp and its oil pressure switch,
however, required a little more
ingenuity. Since it’s a pressure
and not a temperature gauge,
a brass tee could be used to
supply oil to the pressure switch
and the mechanical gauge,
allowing both to coexist. Here’s
the assembly being test fitted.
15
18
Simply installing a rubber grommet
in the firewall pass-through to
protect the gauge tubing from the
sharp sheetmetal will still leave
an open area that allows noise and
underhood odors into the passenger
compartment. Instead, a soft rubber
sheetmetal plug was slit to the
center, a 5/16-inch hole was made
in the middle, and it was installed
around the tubing to better seal the
area, yet still allow for flexibility.
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except for a small piercing in the insulation. No tools are required, they can be removed and they are reusable. Posi-Locks
are also available to attach two wire ends and Posi-Twists can
connect two, three or more wire ends.
A third, and the most permanent procedure, is to solder the
wires together and wrap them with heat shrink tubing, which
requires some additional skill and practice and a soldering iron
or torch, 60/40 rosin core solder and the heat shrink tubing.
There’s plenty of debate as to which methods are better or
worse. Nevertheless, SW confirmed that any of these approaches is satisfactory.
• The price of “Utility”: The Utility line gauges,
like the oil pressure and water temp used for this project, were
offered with and without lighting in some years. When they
came with lighting, only two slots were used at the top. Deluxe
gauges, like the voltmeter I used, have two slots at the top and
two at the bottom. If you wanted to install this panel on top
of the dash, like some racers used to do, turning it over would
put the lamp mounts at the bottom, which won’t work with the
Utility gauges, so an SW Replacement Light Kit part No. 366CH
would be required. It also means that Deluxe gauges have the
option of getting more light in if bulbs are mounted in the top
and bottom of the gauge panel, whereas the Utility gauges don’t.
Now that you know much of what was contemplated regarding this project, follow along as a set of vintage Custom Green
Line gauges finds a new home in a muscle car.
22
19
The voltmeter was slid into the panel, and its bracket and wiring were
installed as shown previously. The new gauge wiring was zip tied every
few inches under the dash, then routed up over the steering column and
pedal mounts and down to the fuse box.
20
The red positive feed for
the voltmeter was added
to a 12-volt switched
circuit via a fuse tap,
and the black wire for
the gauge lamps was
attached to the instrument
panel lamp circuit using
the same method. Both
were installed on the
cold side of the circuit to
ensure that they would
be protected by their
respective fuses. (Those
empty spade terminals
in the fuse box all get
12-volts constant power,
so they couldn’t be used).
21
If you prefer to tap into the wires directly, with a Posi-Tap, the source
wire is slid into the slotted endcap to center it for the metal probe in the
body to pierce it when the two are screwed together. The new stripped
wire is then inserted into the threaded collar. As it’s tightened, the
wire makes contact with the metal conductor inside and is locked in to
complete the electrical connection.
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All mechanical and electrical connections were rechecked prior to
reconnecting the battery, starting the Buick and running it up to
operating temperature. The gauge lighting is switched on and off
and dimmed via the headlamp switch. Here you can see some of the
shortcomings of the slot lighting. The oil pressure gauge is evenly lit
because it has bulbs on both sides, but the outer gauges only have a
lighting source for one side. Possibly, an SW Replacement Light Kit part
No. 366CH mounted near the outer slots of those gauges would even
out their illumination. Once the engine was shut down and it cooled, all
fittings were once again checked for tightness. Now cruising will be less
stressful with gauges reporting on the underhood happenings, while
looking period correct.
parts list:
• Gauges
• Gauge panel, preferably with lamp mounts
• Copper, nylon or braided-steel oil pressure line kit
• 18 American Wire Gauge (AWG) stranded red wire
• 18 AWG stranded black wire
• 22-18-gauge ring terminals for the 18-AWG wires
• Insulated female connectors for 18-AWG wires
• Heat-shrink tubing
• 1-inch black rubber sheetmetal plug
• 6-feet vacuum hose
• 1/4-inch NPT brass pipe tee
• 1/4-inch NPT hex nipple
• Pipe thread compound TFE paste
• Fuse taps (optional)
• Posi-Tap 16-18 AWG (optional)
• Posi-Lock 18-24 AWG (optional)
• Soldering iron or torch (optional)
• 60/40 rosin core solder (optional)
Source:
Stewart Warner • www.stewartwarner.com • 717-581-6410