tach guages

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Lyons Pride
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tach guages

Post by Lyons Pride »

where does the 100 yanmars take the rpm readings from as mine isn't working and I am assuming i moved a wire or 2 doing work on the port motor and now the gauge doesn't work.
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James Power
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Re: tach guages

Post by James Power »

The rpm sender has 2 wires attached to it and is mounted on the flywheel housing at about the 10:00 position when looking forward. If the alternator has been replaced it may also have an rpm output wire.

James
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Re: tach guages

Post by makala »

Yes, it is off of the flywheel. The + wire is orange, - wire is black.

The output of the tach sensor is 127 pulses per revolution. My Yanmar tachs are so far off (port is 1000 rpm off on the port side flybridge!), I installed an Actisense EMU-1 NMEA engine monitor, and it works beautifully (project post coming soon).

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Doug
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Re: tach guages

Post by AMCarter3 »

Doug,

Could you clarify exactly how you connected the Actisense EMU-1 NMEA engine monitor to engine and your NEMA network?
Mac Carter
2006 34' PDQ PowerCat "All Heart"; MV 98; twin 100 HP Yanmars
Home Port: Bellingham WA 98229
AlanH
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Re: tach guages

Post by AlanH »

Mac,

When I replaced my old navigation system with a Raymarine system, I had the electronics guy install a Actisense EMU-1 also. It takes analog data and converts it to NEMA 2000 digital and can be sent to any NEMA 2000 compatible multi function display. My tachs work fine but I had them wired to the Actisense and can display them on the chartplotter. I believe they are hooked up to the analog feed to the back of the tachs at the lower helm. The Actisense is mounted in the main wiring cabinet.

At the same time, I had the oil pressure and water temp connected so I have gauges on the flybridge. I believe they are also connected where the analog wiring connects to the gauges at the lower helm. I also had bilge high water and exhaust high temp alarms installed and piped into the Actisense and chartplotter. It has been four years and it all works great.

Alan
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AMCarter3
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Re: tach guages

Post by AMCarter3 »

Interesting. I get how the RPM data shows on a multifunction panel. Do you have a picture of your flybridge helm showing where you added the temp and oil pressure gauges for both engines?
Mac Carter
2006 34' PDQ PowerCat "All Heart"; MV 98; twin 100 HP Yanmars
Home Port: Bellingham WA 98229
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Re: tach guages

Post by duetto »

hi all,

my question: in the all analog original system, does the inaccuracy of the tachs come from the sensor or the tach gauge?
john & diane cummings
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Re: tach guages

Post by makala »

In the analog system the error is likely due to the wiring lengths and/or tach gauges. The sensor outputs 127 pulses per revolution, pretty cut and dry, and is likely all or nothing at the sensor output location. It's downstream of that where the error occurs.

The EMU-1 instructions state to mount the EMU-1 unit as close to the engine as possible, which makes sense because that eliminates noise, capacitive coupling, and resistance differences due to longer lengths of wire. In my setup (which I will post soon, just need a couple more pictures), I mounted the EMU-1 units (yes you need two) inside the aft closets, on the wall just near the berth. The main engine harness passes through the "floor" just to the inside of the top engine cover at a great location where you can EASILY tap into any of the engine wires here using a positap connector, they work great. It's a small jog from that location to the EMU-1 inside the closet.

So what happens is the analog signals from the engine harness only travel a few feet to the EMU-1, where the signals are digitized and sent over the NMEA 2000 via a network cable to the GPSMAP or whatever NMEA 2000 compliant chartplotter you may have. Then you simply make custom gauge setups on the chartplotter, you don't need any additional analog "gauges".

So far I have hooked up the coolant temperature (value), oil pressure (value), RPM's, coolant temperature switch (alarm), oil pressure switch (alarm), and battery voltage. I am also going to hook up a custom temp sensor and switch (alarm) at the exhaust elbow, which will give me immediate notice if the cooling water is not normal at the elbow (coming soon in a post also with all the details including parts list). These sensors are very reliable and relatively cheap.

In my opinion this setup allows real time engine health monitoring- its amazing how accurate the RPM's and coolant temps are, you can see when the thermostats are regulating (they are spot on within one degree!). This setup, although somewhat expensive, is much less expensive than the alternative of overheating an engine or starting a fire (elbow overheat) or losing engine oil pressure suddenly (if you have reverso system to drain your oil, check your clamp {mine was slightly loose but I caught it leaking}, as I see that it could easily let go and leave you with zero oil pressure). I will also know if the heat exchanger is starting to get blocked since I know historically how the engine behaves. It basically lets you set a baseline of sorts.

BONUS: The EMU-1 will keep track of engine hours!! Our Yanmar LCD port hour meter is intermittent, so the EMU-1 will allow me to know actual hours if when the Yanmar LCD fully dies. :P

Im in the process of installing a Victron SmartShunt to monitor battery health, that post will also be coming soon.

Anyone have a recent solar setup project to share? Been thinking about that project...

Hope that helps.

Thanks,
Doug
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Re: tach guages

Post by AlanH »

Mac,

I think Doug's explanation covered your question but, I do not have traditional gauges on the flybridge. The oil, temp and tach data is fed into a page you set up on the chartplotter. I have both a separate page for engine data and a split page with engine data and a navigation map sharing on a 12" screen.

Alan
Alan Hendry
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