MSD 83506 Ford 351-460 Ready-to-Run Marine Distributor Installation - Manual (Page 7)

INSTALLATION INSTRUCTIONS 7
M S D
• W W W . M S D P E R F O R M A N C E . C O M • ( 9 1 5 ) 8 5 7 - 5 2 0 0 • F A X ( 9 1 5 ) 8 5 7 - 3 3 4 4
TACHOMETER INFORMATION
The MSD Ready-to-Run has a Green wire that provides a 12 volt square wave, 20° duty cycle tachometer
signal that will trigger most tachometers. It is recommended to connect this lead to your tach’s trigger
input wire and check its operation. Note that the rpm limiter is extremely accurate and due to the variety
of tachometers available, there may be differences in the displayed rpm.
PROGRAMMING THE REV LIMIT
A tachometer is required to set the rev limit. The limit is programmed by
running the engine at half the desired rpm, then momentarily grounding
the Green tach output wire from the MSD. A Green jumper wire is
supplied to connect to the tach with another tee-splice coming off to use
for programming. A switch may also be installed to ease adjustments of
the limiter (Figure 13). The default rpm limit is 10,000 rpm and the limit
is adjustable from 2,000 - over 10,000 rpm..
1. Start the engine and bring the rpm to half the desired rev limit (for a
6,000 rpm limit, raise and hold the rpm to 3,000).
2. While holding the rpm steady, short the Green tach wire to ground
for approximately one second. Note that the tach will go to zero
while grounded.
3. The tach will now display the programmed rev limit amount for two
seconds. If this value does not register on the tach, repeat the procedure and try a different ground
source.
4. To confirm the rev limit value, turn the ignition key to the On position (without cranking the engine). The
rev limit value will be displayed for two seconds on the tachometer.
Note: This rpm confirmation only displays when the Green wire is being used to trigger the tachometer.
TO
TACH
OPTIONAL
PROGRAMMING
SWITCH
JUMPER GREEN
Figure 13 Setting the Rev Limiter.
TECH NOTES
_________________________________________________________________________________________________________________________
_________________________________________________________________________________________________________________________
_________________________________________________________________________________________________________________________
_________________________________________________________________________________________________________________________
_________________________________________________________________________________________________________________________
_________________________________________________________________________________________________________________________
_________________________________________________________________________________________________________________________
_________________________________________________________________________________________________________________________
_________________________________________________________________________________________________________________________
_________________________________________________________________________________________________________________________
_________________________________________________________________________________________________________________________
_________________________________________________________________________________________________________________________
_________________________________________________________________________________________________________________________
_________________________________________________________________________________________________________________________
_________________________________________________________________________________________________________________________
_________________________________________________________________________________________________________________________