Digatron DT-31RI User manual

DT-30RI SERIES INSTRUMENT INSTALLATION INSTRUCTIONS
IMPORTANT
Thoroughly read all of the installation instructions before
attempting to install your instrument. Failure to do so could
result in damage to the instrument or other problems arising.
These instructions cover the installation of all sensors in
the “30RI” series. You need only those that apply to your par-
ticular Model.
If you have any questions about the installation or prob-
lems with the instrument, call the DIGATRON Technical Serv-
ice Department at [phone].
BATTERY INSTALLATION
Your instrument is supplied with a fresh set of batteries in-
stalled. When it is time to replace the batteries, remove the
battery cover from the instrument and remove the old batteries.
Install 4 new AA batteries in the battery holder paying atten-
tion to the polarity markings inside the battery holder.
Before reattaching the battery cover, check the battery
pressure pad on the inside of the battery cover. This pad must
apply pressure to the batteries when the cover is in place. Er-
ratic instrument readings may be experienced if the batteries
move around excessively during use.
For longest battery life, we recommendalkaline batteries.
INSTRUMENT INSTALLATION
Before you begin cutting and drilling your dash panel, two
conditions should be met whenever possible.
1: A distance of at least 6" must be maintained between the
instrument and any ignition components (plug wires, spark
plugs, ignition coil, distributor, or magneto) to prevent electri-
cal interference from affecting the operation of the instrument.
2: Access to the rear of the instrument should be provided
to allow for connecting and disconnecting the sensors. Easy
removal of the instrument from the dash panel is also needed
for battery changes.
For dash panel mounting the instrument, a correctly sized
rectangular opening in the dash panel is required. ( A template
is provided with each instrument for your convenience.)
Below is a chart showing the size of the opening required
for each model.
MODEL REAR MOUNT
DT-31 3.500” x 4.500”
DT-32 3.500” x 4.050”
DT-33 3.500” x 6.600”
DT-34 3.500” x 6.600”
DT-35 3.500” x 9.000 ”
GROUNDING
If the instrument is not mounted in a well-grounded alumi-
num dash panel, run a grounding wire from the instrument’s
mounting bracket to a near by ground point. Keep this wire as
short as possible.
The engine of the vehicle should also be grounded to the
chassis by a wide, braided ground strap (1/2" or wider and as
short as practical) for best instrument operating results. When
establishing a new ground connection, it is important to make
these connections to clean bare metal. Paint, anodizing, rust
and other contaminants will impede the shorting out of electri-
cal interference which may affect the operation of your instru-
ment. Wire lengths must also be kept as short as possible.
WIRE ROUTING NOTES
The following instructions apply to the sensors that run
from the engine compartment to the instrument. These sensors
should always be routed as far away as possible from the igni-
tion system components. (plug wires, spark plugs, ignition
coils, distributor or magneto). Leads too close to these compo-
nents may pick up radiated electrical interference and cause
erratic instrument readings and operation. A distance of at
least 6" from these components is desirable in all installations
Route all the sensor wires from the engine into the driver's
compartment through a protected opening in the firewall. The
opening must provide protection against the sharp metal edges
of the hole. Large rubber grommets available from most auto
supply or hardware stores work best.
Do not coil sensor wires together. Keep the individual
sensor wires separated as much as possible. Separating the
wires will help to eliminate the induction of electrical interfer-
ence from one sensor into the other sensor leads. Induced
interference will cause erratic instrument readings.
Exhaust Sensor leads must not be routed together with any
Tach Sensor leads. Provide a totally separate routing path for
the Tach Sensor lead.
DO NOT OPERATEthe instrument with any disconnected
or open inputs. Unused instrument inputs must be terminated
at the back of the instrument with a shorting plug available
from DIGATRON. Inputs that are left open can cause erratic
display readings and in some instances, instrument damage
can result.
DASH INDICATOR WARNING LIGHT
P/N DI-118BN Mount the Dash Indicator light directly
in the driver's line of sight in the dash panel. The indicator
mounts in a 1/2" diameter hole. It is important that the driver
be able to see this indicator while driving without looking
away from the track.

After drilling and deburring the 1/2" hole in the dash panel,
place the aluminum indicator bezel through the hole from the
driver compartment. Press the retaining washer on to the back
side of the aluminum bezel. (Takes a lot of pressure.) Insert the
lamp assembly through the back of the bezel into the lens.
Press the plastic retaining plug into the rear of the bezel to se-
cure the lamp assembly in place. Connect the lead to the Or-
ange connector on the back of the instrument. Twist the con-
nector 1/4 turn to lock it in place.
EXHAUST TEMPERATURE SENSORS
P/N EXT-1 *** RBN Because the EGT sensor leads are
the most sensitive to ignition interference or electrical interfer-
ence, it is recommended that the probes be installed in the rear
header tubes of a front engine vehicle and in the front header
tubes of a rear engine vehicle. Installed in this manner it will be
easier to route the leads to maintain the recommended distance
from ignition components. Install the sensor into the header at
a point approximately 2" from the head side of the exhaust
flange. Drill a 13/64" hole in a location in the header which will
allow easy access to the sensor. Install the exhaust clamp as-
sembly on the header aligning the compression fitting base
with the drilled hole in the header. The tip of the sensor should
be located at a point approximately 1/4" past the center of the
header. Tighten the compression fitting nut to secure the sen-
sor in place. Tighten the clamp assembly to secure it to the
exhaust header. Route the sensor wires to the instrument pay-
ing particular attention to the routing precautions outlined
earlier. All exhaust temperature sensors use the same color
boot on their connectors. You may want to use a permanent
marking pen on the boot to code the leads from the engine
Connect the sensors to the Gray terminals on the back of
the instrument. The placement of the terminals on the instru-
ment corresponds with the window that EGT is displayed in..
Twist the connector 1/4 turn to lock it in place.
The long black wire near the sensor probe must then be at-
tached to a convenient ground point on the engine. This wire
is covered with a high temperature Teflon that can withstand a
good deal of heat but should not rest on top of the header
pipes.
Repeat this process for any remaining exhaust sensor(s).
NOTE: The Exhaust Temperature Sensor leads are the
most susceptible to electrical interference. In extreme circum-
stances where electrical interference cannot be eliminated by
following the outlined procedures, try the following sugges-
tions. Route your Exhaust Temperature Sensor leads through
a grounded metal tube to the instrument.
REMOTE STORE SWITCH
P/N SA-CBN The Remote Store Switch should be
mounted in a steering wheel spoke within thumbs reach of the
driver. This switch requires a 15/32" mounting hole for installa-
tion. If a steering wheel spoke is not available to accommodate
the switch, a bracket must be fabricated for mounting. Mount
the bracket to the steering wheel in a position that will provide
easy access to the switch while driving.
Tie the coil cord to the steering wheel and or column where
needed to prevent it from interfering with the driver. Connect
the lead to the White connector on the back of the instrument.
Twist the connector 1/4 turn to lock it in place.
OIL TEMPERATURE SENSOR
P/N 0T-1 *** BN Any port normally used to monitor
the oil temperature may be used for the Oil Temperature Sen-
sor. The compression fitting supplied with the sensor is a
standard 1/8" Iron pipe thread. Insert the end of the sensor
through the compression fitting into the oil to a depth of at
least 1". Tighten the compression nut to secure the sensor in
place.
Route the sensor wire to the instrument, paying attention
to the above wire routing notes. Attach the lead to the Yellow
connector on the rear of the instrument. Twist the connector
1/4 turn to lock it in place.
In some installations, a reducing bushing may be required
to adapt the compression fitting to an available oil temperature
port.
WATER TEMPERATURE SENSOR
P/N WT-1 *** BN The location of the Water Tempera-
ture Sensor should be well below the water level in the engine
block or in a location provided in the engine for the purpose of
monitoring water temperatures. Do not use the radiator for
monitoring water temperature readings. The water temperature
sensors use the same compression fitting as the oil tempera-
ture sensor.
Route the sensor wire to the instrument, paying attention
to the above wire routing notes. Attach the lead to the Red
connector on the rear of the instrument. Twist the connector
1/4 turn to lock it in place.
In some installations, a reducing bushing may be required
to adapt the compression fitting to an available water tempera-
ture port.
TACH SENSOR INSTALLATION NOTE
If this instrument has a Tach function included as a stan-
dard feature, the tach sensor must be connected to the ignition
system to provide a tach signal to the instrument. If this lead is
not used the instrument will automatically turn itself off after a
period of approximately 10 minutes.
Digatron builds three general types of Tach Sensors de-
signed for different types of ignition systems. A sensor de-
signed for a CDI type ignition will not work on a vehicle with a
magneto. If you change to another type of ignition system, do
not connect the old tach sensorto this new system. SERIOUS
instrument damage may result from using the wrong Tach Sen-
sor.

DBN Type TACHOMETER SENSOR
P/N TS-1 *** DBN This type of Tach sensor is de-
signed for use with electronic ignition systems with an Auxil-
iary Tach output connector on the ignition.
Attach the spade connector from the tach sensor to the
tach output on your ignition system. Route this sensor lead
keeping it as far from your other leads as practical to the
back of the instrument. Attach the lead to the Blue connector
on the back of the instrument. Twist the sensor connector 1/4
turn to lock it in place. Note: There is a resistor installed in the
ignition end of this sensor lead. Do not attempt to shorten the
tach lead without replacing this resistor.
MBN Type TACHOMETER SENSOR
P/N TS-1*** MBN This type of Tach sensor is de-
signed for use with electronic ignition systems without an
Auxiliary Tach output connector on the ignition.
Attach the ring terminal from the tach sensor to the nega-
tive side of the coil on your ignition system. Route this sensor
lead keeping it as far from your other leads as practical to
the back of the instrument. Attach the lead to the Blue connec-
tor on the back of the instrument. Twist the sensor connector
1/4 turn to lock it in place. Note: There is a resistor installed in
the ignition end of this sensor lead. Do not attempt to shorten
the tach lead without replacing this resistor.
NOTE: If the Tach does not work as connected, switch
the sensor connection to the positive side of the primary
winding.
M-5BN Type TACHOMETER SENSOR
P/N TS-1 *** M-5BN This type of Tach sensor is used
on non electronic ignitions that use a mechanical (point)
mechanism to generate the spark. Attach this sensor to the
point side of the coil primary winding.or to the magneto side
of the kill switch. This sensor lead has electronic components
built into the boot on its terminal end. Serious instrument
damage will result if these components are removed.
Route this sensor lead keeping it as far from your other
leads as practical to the back of the instrument. Attach the
Blue sensor connector to the Blue connector on the back of
the instrument. Twist the sensor connector 1/4 turn to lock it in
place.
OIL PRESSURE SENSOR
P/N OP-150S and OP-EXT-1 *** SBN The Oil Pres-
sure Sensor will replace the one you are currently using. The
sensor will monitor pressures up to 150 PSI. Mount the sen-
sor directly to the engine block or to a steel braided hose with
an added grounding wire. When locating the sensor, remember
to avoid the ignition system. If using a braided hose to attach
the sensor, a clamp will be required to mount the sensor se-
curely. (A 1 3/4” muffler clamp works well for this purpose) Be
sure that the clamp assembly is grounded to the block. Attach
the Sensor Extension terminal end to the post on the rear of
the sensor.
Route this sensor extension lead to the instrument paying
attention to the wire routing notes listed earlier. Attach the
Green sensor extension connector to the Green connector on
the back of the instrument. Twist the sensor connector 1/4 turn
to lock the connector in place.
NOTE: Oil pressure in a cold engine is always the greatest
when the engine is first started. You may want to delay turn-
ing on the instrument until the engine has been warmed up to
eliminate this high pressure reading from being retained as the
maximum reading in the instrument's memory.
FUEL PRESSURE SENSOR
P/N OP-16S and FP-EXT-1 *** SBN -16 PSI.
P/NOP-150S and FP-EXT-1 *** HBN -150 PSI.
The Fuel Pressure Sensor supplied with your instrument will
monitor pressures up to16 PSI for the OP-16S or150 PSI for
the OP-150S.
This sensor should be installed into the fuel system to
monitor the fuel pump outlet pressure. The sensor should be
mounted in the same way as the Oil Pressure Sensor. Attach
the Sensor Extension terminal end to the post on the rear of
the sensor. Route this sensor extension lead to the instrument
paying attention to the wire routing notes listed earlier. Attach
the Brown or Violet sensor extension connector to the Brown
or Violet connector on the back of the instrument. Twist the
sensor connector 1/4 turn to lock it in place.
NOTE: If you are burning alcohol, you must remove the
sensor after draining your fuel. Alcohol vapors will damage the
seals in the sensor.
POST INSTALLATION NOTES
Before washing the vehicle, the instrument should either be
removed or protected from getting wet. Moisture will normally
not harm the instrument. If the instrument does get wet inter-
nally it may not work properly until thoroughly dried.
If during use your instrument seems to get lost (displays
nonsensical numbers) and will not respond to it’s switches,
you can usually reset it by turning the engine off, and then
removing and reinstalling one of its batteries. This condition
can be caused by electrical interference from the ignition, poor
sensor connections, bad grounds or even moisture entering
the instrument.
If you are getting erratic readings on your instrument and
have checked to be sure that all sensor leads are the recom-
mended distance from the ignition components and that the
instrument is well grounded, you may need a new set of
“magnetic suppression” type plug wires. Digatron highly rec-
ommends the use of Moroso “Blue Max.” Spiral Core or MSD
Heli-Core plug wires.