Adding a Yanmar 1GM10 Tachometer?

[AnsleyS]

That looks good. Find yourself a meter that you like. It will need calibration when you install it.

[TooCoys]

Originally Posted by AnsleyS

That looks good. Find yourself a meter that you like. It will need calibration when you install it.

Does 1.7 kilohms translate to 1700rpms?

[AnsleyS]

Probably not. What you can't see with that little meter is the fluctuation of the readings​. The sensor reacts when a small magnet on the wheel flies by it. The number of reactions in a period of time is translated into RPM. An oscilloscope would show it to you but... Go to a local auto parts store and ask them. You need a 12 volt magnetic pickup tach.

[GordMay]

See ➥ Magnetic Proximity Tachometer - Tachometer Wiring Diagram Cruisers & Sailing Photo Gallery

[MCOS]

Check out TINYTACH , the connection to the engine is a clamp on the injector line, just clamps over the pipe - does not pierce the pipe. It picks up the pulses of the fuel injector and connects to a small digital read out by a thin wire. About $100 US. shop around you might find it cheaper. I paid $89 including postage about 5 years ago. It works great.

[TooCoys]

I've seen the TinyTach, doesn't appeal to me.

[pcmm]

Originally Posted by AnsleyS

Probably not. What you can't see with that little meter is the fluctuation of the readings​. The sensor reacts when a small magnet on the wheel flies by it. The number of reactions in a period of time is translated into RPM. An oscilloscope would show it to you but... Go to a local auto parts store and ask them. You need a 12 volt magnetic pickup tach.

The yanmar sensor doesn't work like that. it is calibrated by the number of teeth on the flywheel. when you order a replacement Yanmar tach you have to specify the exact model of tach so it's calibrated to the flywheel. A bit of a PITA system but its reliable!

[jmccraw]

I purchased a new programable diesel tack that reads to 4K rpm eBay.. There is a small rotary switch on the back that is set for numbers of teeth on the fly wheel in groups Like 90-100, 100-110, 110-120 etc. My Yamar 2QM15 had about 128 teeth on the flywheel. Each time a tooth passes under the magnetic pickup it generates a pulse. After setting the switch for the correct range of teeth there is a small pot that is adjustable to dial in the correct rpm on the tach face. To get the correct rpm go to harbor freight and purchase a optical tach for under $40. It has a strip of shinny material that you place on the belt drive on the front of the engine. Shine the light at the strip while the engine is running and read the engine rpm. Have a friend in the cockpit rotate the the pot on back of the tach for the correct rpm. Done!!! The wires on the Yanmar harness hook to the tach and sensor.
Call me for help
Jim 417-848-3773

[TooCoys]

Originally Posted by jmccraw

I purchased a new programable diesel tack that reads to 4K rpm eBay.. There is a small rotary switch on the back that is set for numbers of teeth on the fly wheel in groups Like 90-100, 100-110, 110-120 etc. My Yamar 2QM15 had about 128 teeth on the flywheel. Each time a tooth passes under the magnetic pickup it generates a pulse. After setting the switch for the correct range of teeth there is a small pot that is adjustable to dial in the correct rpm on the tach face. To get the correct rpm go to harbor freight and purchase a optical tach for under $40. It has a strip of shinny material that you place on the belt drive on the front of the engine. Shine the light at the strip while the engine is running and read the engine rpm. Have a friend in the cockpit rotate the the pot on back of the tach for the correct rpm. Done!!! The wires on the Yanmar harness hook to the tach and sensor.
Call me for help
Jim 417-848-3773

If I remember correctly, the 1GM10 has 72 teeth on the flywheel.