Tachometer
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Optional for the Datsun 1200 was an 8,000 RPM Kanto Seiki tachometer. It was usually housed in the round-gauge instrument panel to the left of the speedometer. It may also be placed in the optional floor console.
Index
[[Tachometer#H18|
]] [[Tachometer#H23|
]] [[Tachometer#Facelift|
]] http://datsun1200.com/uploads/photos/29792.jpg [[Tachometer#10.2C000_RPM_Tachometer|
]]
Overview
All B110 tachometers look similar, with scale that goes to 8000 RPM. The normal unit has a redline that starts at 6400 rpm, the GX starts at 6800 and the PB110 at 7500. The Datsun #620 Tachometer has a 7000 rpm redline.
[[1972#29368|
]] [[1972#29369|
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The tachometer is electrically operated and indicates engine speed calibrated in hundreds of revolutions per minute (rpm). two color zones are on its face. For normal driving, your vehicle should be driven in the yellow or non-color sectors.
The standard tachometer has a 6400 rpm redline
Options - Tachometer was optional on DX or GL round dash models. Standard equipment on the GX.
[[Options#North_America|
]] 
Ute can be retro-fitted with a tacho. No factory tachometer is listed for Sunny Truck, but only a Clock. Even so it is common to see tachometers installed in 1200 Trucks, as they fit the same.
Bottom stay is the ground/earth point
Location
The factory Parts Catalog shows GL came with a clock in the dash, while the GX came with an 8,000 RPM tachometer in the dash and the clock was moved to the floor console.
Dash
B110
PB110
Dash Fitting
Mounting tabs (red arrows). The plastic lens is attached with three smaller screws (yellow arrows).
Remove the facia with attached gauges from the dashboard
Unscrew the blanking plate
Finally, use the three screws to attach the tachometer
Tacho in dash, blank plate in Console
factory GL configuration
Tacho in dash, Clock in Console
factory GX configuration
Tacho in Console
Specials Datsun 1200 SSS and Datsun 1200 S1 placed the tachometer in the floor console. It is preferable to have the Tachometer at eye-level, however these models came with square-gauge dashes so the large round tachometer was placed in the console.
SSS | S1
The factory tachometer was not designed to bolt to the console. But it will fit if you make a simple bracket to hold it in place.
Wiring
Main: Tachometer_Wiring
Part Numbers
#H18 24855-H1800 1200 TACHOMETER 8000 RPM [6400 redline]
#H23 24855-H2300 1200 TACHOMETER 8000 RPM GX http://datsun1200.com/uploads/photos/29791.jpg
#24855-H1075 1200 FACTORY RACE TACHOMETER * Calibrated to 10,000 RPM with adjustable redline needle
#H31 24855-H3100 1972 B110 8000 RPM [Facelift] (Except GX)
#H34 24855-H3400 1972 B110 GX 8000 RPM [Facelift 6800 redline] 
364/384 facelift tachometer plastic on old-style tachometer
http://datsun1200.com/uploads/photos/29793.jpg http://datsun1200.com/uploads/photos/29794.jpg
26061-B140 Allied Engineering for B140
H18
H18 is the Coupe Applied Model Code. This same tachometer was optional on Sedan. It was never advertised for van or truck, although they use the same dashboard so it will bolt up. But the wiring may or may not exist on the wagon or ute.
24855-H1800 1200 TACHOMETER 8000 RPM [6400 redline] KANTO SEIKI TOKYO 4CYL * Yellow: 6000-6400 * Red: 6400-8000 * ~110mm across
http://datsun1200.com/uploads/photos/29788.jpg http://datsun1200.com/uploads/photos/29789.jpg http://datsun1200.com/uploads/photos/29790.jpg
The Datsun 1200 GX came with 6800 rpm redline. The other tacho has a redline that starts at 6400 rpm. The yellow line indicates you have revved beyond peak HP. The redline is higher than a non-GX engine as valve float doesn't occur until after 6800. This is because of the dual valve springs allow higher RPM.
H23
24855-H2300 1200 TACHOMETER 8000 RPM GX
http://datsun1200.com/uploads/photos/29791.jpg
Facelift
H31: DX, GL option (6400 RPM redline) #H34: GX with 6800 RPM redline
The 1972 minor facelift made several changes to the tachometer.
* New anti-glare cover * New colors * long stay bolts to hooded facia
New anti-glare cover (cone shaped)
New Font, new colors
Now includes long stay to reach hooded facia
Gauges have long-reach brackets, but old tacho will bolt up
Old tachometer can installed using flat-plastic cover (as shown) or the new-style anti-glare cover
H31
H31 option tachometer with 6400 rpm redline (non-GX)
H34
H34 GX tachometer with 6800 rpm redline
Includes long top stay to reach hooded facia (GX: 6800 RPM redline)
H34 with original wiring (current loop)
Adjustment
Adjust the RPMs using the trimmer slot on the back of the tachometer. Take a reading using a dedicated (accurate) Dwell-Tachometer, and if your tachometer reads off, adjust it to match.
The factory tachometers have an adjustment via is a trimmer pot (potentiometer) on the back of the tachometer. Use a thin screwdriver to make the adjustment. It can be accessed from the back of the tachometer. The access hole is above the bottom tab. Rotate the pot clockwise or anti-clockwise to adjust.
Yellow Arrow points to the trimmer pot
Electronic Ignition
The stock tachometer works with most types of Electronic Ignition.
- If using a single coil with the stock ballast resistor, works the same
- If using coil packs, use the "Tach Out" signal on the ECU or Ignition Controller
- Aftermarket tach (voltage trigger type): If using a "high energy" system (no ballast resistor) you may need to add a 1.5 ohm resistor inline with the tach wire
The tach may jump around and misbehave with a new ignition module. A condenser on the coil negative wire can help with this.
V8
The stock tachometer will work with a V8 engine, but will read half of the actual engine speed.
Ditto for a six-cylinder engine (inline i6 or V6), it will read 1/3 slow. This can sometimes be compensated using the #Adjusment on the back of the tachometer.
For a V8, add a 15k ohm resistor between the tachometer circuit board and the tachometer movement.
LATE 1200 tachometer (voltage sense type) 8-cylinder 15k resistor
Some later Datsuns use a 2.2k resistor inline with the coil to reduce noise. In a 280Z it is located in the passenger side footwell. In a 720 it is located in the engine compartment. This is for a the late tachometer (620) or aftermarket tachometers, and doesn't apply to the stock 1200 inductive tachometer. This resistor is not needed for proper tachometer operation but can help in electrically noisy environment.
620 Tachometer
The Datsun 620 truck tachometers fits Datsun 1200 and looks very similar. But 620 models with L20B engine have 7000 rpm red line (1200 tach has 6400 or 6800 rpm redline).
1976-1979 USA 620 Tachometer [7000 redline]
http://datsun1200.com/uploads/photos/29792.jpg 
620 in Japan did not have a factory tachometer option.
1972-1975 early 620 USA * 24840-B6400 KIT-TACHOMETER OP -0775 * 24054-B6400 ASSY-CABLE,TACHOMETER 
1976-1979 late 620 USA * 24855-B8000 ASSY-TACHOMETER OP 0875- * tachometer wiring is built into every 1976-1979 620
The later Tachometer Wiring is different. It is a typical tap connection, instead of the Datsun 1200 'passthru' induction wiring.
Comparison
1200 and 620 tachs are wired completely different. See Tachometer Wiring.
620 Tachometer has no wiring loop:
Early 1200 Tachometer has wiring loop:
Bprojects
Bprojects Sunny Truck tachometer☁, looks like genuine dash tachometer, but has different redline. It mounts in the dash, and is lacking console mounting brackets.
6500 RPM redline
https://i297.photobucket.com/albums/mm219/ddgonzal/Datsun%201200/wiki/b110-tacho-003.jpg https://i297.photobucket.com/albums/mm219/ddgonzal/Datsun%201200/wiki/b110-tacho-003003.jpg
Green to Illumination Black to Earth Red to I/G 12V Yellow/red to ignition coil - (minus)
https://i297.photobucket.com/albums/mm219/ddgonzal/Datsun%201200/wiki/b110-tacho-007.jpg https://i297.photobucket.com/albums/mm219/ddgonzal/Datsun%201200/wiki/b110-tacho-008.jpg https://i297.photobucket.com/albums/mm219/ddgonzal/Datsun%201200/wiki/b110-tacho-005.jpg https://i297.photobucket.com/albums/mm219/ddgonzal/Datsun%201200/wiki/b110-tacho-006.jpg https://i297.photobucket.com/albums/mm219/ddgonzal/Datsun%201200/wiki/b110-tacho-004.jpg
Nissan Competition
1984 Nissan Competition Catalog
TACHOMETERS
- #24855-H1800 1200 TACHOMETER
- #24855-H1075 1200 FACTORY RACE TACHOMETER Calibrated to 10,000 RPM with adjusable redline needle. Installation same as 24855-H1800.
- 28455-H6200 B210 TACHOMETER (TO 7/75)
- 28455-H7200 B210 TACHOMETER (FROM 8/75)
- 28455-H9100 210 TACHOMETER (TO 12/79)
- 28455-H9021 210 TACHOMETER (FROM 1/80)
#H18 24855-H1800 is the stock factory OPTION tachometer
http://datsun1200.com/uploads/photos/29788.jpg
#24855-H1075 is the 10,000 RPM tachometer
PB110 7,500 RPM Tachometer
http://datsun1200.com/uploads/photos/30526.jpg
10,000 RPM Tachometer
Sunny Sport option also sold by #Nissan_Competition
As you can see, the 10k tachometer has the same case, same font, same wiring. Only the faceplate is different and a moveable tell-tale pointer has been added.
This one has no tell-tale pointer, does not say KANTOSEIKI TOKYO, and the legend (x 1000rpm) is below the pointer instead of SE to the pointer. It also has tape where the dash bracket would normally be
http://datsun1200.com/uploads/newbb/174_6909038bc3fa9.jpg http://datsun1200.com/uploads/newbb/174_690903995785c.jpg http://datsun1200.com/uploads/newbb/174_690903a1c6adb.jpg http://datsun1200.com/uploads/newbb/174_690903abc1dbf.jpg
This one appears to be using the standard lens, with the tell-tale knob having been removed, wires cut, power post missing, and lower mounting bracket hacksawed off
12,000 RPM Tachometer
Kanto Seiki 12,000 RPM tacho.
Mechanical Drive
Datsun Competition offered a mechanical tachometer.
Main: Tach Drive
B310
Main: B310 Tachometer
Aftermarket Tachometers
Main: Aftermarket tachometers
Photo Index
rev counter tacho tach rpm gauge タコメーター
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