EGT and Boost via nmea2000

According to them it should be easily added to a MFD via nmea2k. I like this idea as i can customize my screens to show critical items. You can also setup alarms on your mfd so curious how well that all plays together.

If the alarms come through as ECU engine alarms then they can be pop-up alarms on almost any display. If you configure "gauge" parameters on the MFD then they will only be displayed on similar MFD's gauges as warnings and not popup alarms. At least that is what I have found out with Garmin MFD's, including the GMI 20. An alarm configured as a gauge parameter on the GMI 20 will trigger a warning on the same gauge on the 1243 for example. Another FW update and that might change, but for now that is how it seems to work.
 
EGT can be indicative of overloading and generally speaking the lower EGT (to a point) at a given RPM equals a longer engine life. It can also be caused by low boost, fouled intake path, and other restriction. In our case we had a boost leak through the wastegate lowering boost pressure and engine power ultimately raising EGT.

High EGT also would typically mean high cylinder temps.

directly lowering egt with injection would likely mask the root cause of the issue

I know about keeping the EGT's at or below a certain temp to keep the engine happy over the life. And there is temps that are ok for a time and temps that can be seen but only for a very short time. I have seen the damage to piston tops and skirts caused by high temps for longer than needed. I have also seen sleeves cracked and burned through due to the same.

High fuel or injectors that are worn and not spraying a properly atomized fuel can also cause higher EGT's.

I have seen reduced power and performance due to boost leaks, but have never heard of it causing higher EGT's. I find that interesting. The intake systems I have seen have always been a simple system. Air in to turbo, out to intake. Insert ATA intercooler as needed. And that is where the water injection will and does work. Cooling the intake air temp by putting atomized water droplets into the air causing the intake air temps thus lowering the combustion temps and then the EGT's. I asked because I have no knowledge of the marine system.

I'm just picking the collective brain on this subject. The electronics involved with monitoring and the diesel systems in the marine environment are just fascinating to me. Another thing to learn.

Thank you for entertaining on this.
 
It looks like their latest update supports PGN 130316, pg 460 - https://raymarine.app.box.com/s/3t839g2xf6nko4n0h9re535140rknnpz/file/154895711704
I see where that is now supported in the manual, but I can not find a way to display EGT on the Axiom. Spent an hour looking…

8158EE35-E5D8-4BED-91F1-E11F71F9BBAA.jpeg
 
I see where that is now supported in the manual, but I can not find a way to display EGT on the Axiom. Spent an hour looking…

View attachment 115163

Funny I looked at the Raymarine forum and saw where you asked Chuck that same question and got the PGN supported. But maybe they haven't had anyone use it by now and your the first to find this out. I think another tech support call maybe in your future. I'm all Garmin or I would try and find it on my display to verify. Does the DSM410 see the sensor(s) correctly?
 
Funny I looked at the Raymarine forum and saw where you asked Chuck that same question and got the PGN supported. But maybe they haven't had anyone use it by now and your the first to find this out. I think another tech support call maybe in your future. I'm all Garmin or I would try and find it on my display to verify. Does the DSM410 see the sensor(s) correctly?

I choose Maretron specifically because the support 130316 and can display it.

I wish Raymarine would allow you to custom design pages like Maretrons N2K…screens are awesome…if you own an Yamaha outboard.
 
I choose Maretron specifically because the support 130316 and can display it.

I wish Raymarine would allow you to custom design pages like Maretrons N2K…screens are awesome…if you own an Yamaha outboard.

Yeah, Garmin lets you select from a number of pages and then you can select the data being displayed. I agree a very nice feature.
 
Order up the egt sensor, plugged into my nmea network and now I have egt readings on my Garmins.

366A3435-741A-4009-8106-8ED4E46CB880.jpeg
4072780B-E02A-43D9-B09E-DABEF6B5554F.jpeg
 
The thermocouple should be installed in the manifold. There should be a square boss cast into the manifold just under the turbo. That is where they should be drilled and tapped. Unless there is a bung with a plug already there.
 
26F520B2-0A51-400D-9548-D69567C2FC28.jpeg
Seaboard says to install in between the flange(blue arrow). I think because in the cruisers setup the water is introduced closer. Since my elbow has this plug (red arrow) in it I’m going to try this spot. The water is introduced much further down the elbow.Will check for the plug under the turbo, but not looking to drill and tap manifold if I don’t have to as I’m not sure where the coolant is jacketed.
 
Temp is usually a known in the manifold. As the exhaust goes through the turbo its cooled. Even though it's not much. And the value will be a cooler temp to monitor. How much, I dont know. There should be a known idle temp. You can guesstimate the difference and adjust for the bung down stream.

The square boss is usually under or just before the turbo about an inch to inch and a half.
 
Installed similar nmea 2k boost sensor from acrossoceans yesterday. So far very happy with the setup. Very easy to install and configure.
4BF11EE9-C76D-4E0A-AC70-5AB34F861DF4.jpeg
 
Temp is usually a known in the manifold. As the exhaust goes through the turbo its cooled. Even though it's not much. And the value will be a cooler temp to monitor. How much, I dont know. There should be a known idle temp. You can guesstimate the difference and adjust for the bung down stream.

The square boss is usually under or just before the turbo about an inch to inch and a half.

For CAT 3100 series engines, CAT installed EGT probe boss after the Turbo outlet, and EGT number are published based on that location. I’m not as familiar with Cummins but I think they are similar.
 
I know about keeping the EGT's at or below a certain temp to keep the engine happy over the life. And there is temps that are ok for a time and temps that can be seen but only for a very short time. I have seen the damage to piston tops and skirts caused by high temps for longer than needed. I have also seen sleeves cracked and burned through due to the same.

High fuel or injectors that are worn and not spraying a properly atomized fuel can also cause higher EGT's.

I have seen reduced power and performance due to boost leaks, but have never heard of it causing higher EGT's. I find that interesting. The intake systems I have seen have always been a simple system. Air in to turbo, out to intake. Insert ATA intercooler as needed. And that is where the water injection will and does work. Cooling the intake air temp by putting atomized water droplets into the air causing the intake air temps thus lowering the combustion temps and then the EGT's. I asked because I have no knowledge of the marine system.

I'm just picking the collective brain on this subject. The electronics involved with monitoring and the diesel systems in the marine environment are just fascinating to me. Another thing to learn.

Thank you for entertaining on this.
Water injection or methanol injection will cool and densify the air charge which is a good thing. On electronically managed diesel engines there is an air temperature sensor and air pressure (boost) sensor that the engine management system uses to control fuel flow to the cylinders. Control, that is, to a point then things are out of limits and engine damage could occur. The turbocharger will provide XX amount of air so if the charge is cooled to a point of pressure drop a larger turbocharger may be needed. On diesel powered engines the fuel demand is really based not only on the intake air temperature and pressure but on load demand from the throttle and load from rpm. As more throttle is applied the engine will fuel to achieve the desired RPM. The problem becomes when throttle position (load demand) is too high relative to the RPM (load) and the excessive fueling to achieve/maintain the desired RPM causes high EGT's. This is exactly why we take pitch out of the propellers.
 
Water injection or methanol injection will cool and densify the air charge which is a good thing. On electronically managed diesel engines there is an air temperature sensor and air pressure (boost) sensor that the engine management system uses to control fuel flow to the cylinders. Control, that is, to a point then things are out of limits and engine damage could occur. The turbocharger will provide XX amount of air so if the charge is cooled to a point of pressure drop a larger turbocharger may be needed. On diesel powered engines the fuel demand is really based not only on the intake air temperature and pressure but on load demand from the throttle and load from rpm. As more throttle is applied the engine will fuel to achieve the desired RPM. The problem becomes when throttle position (load demand) is too high relative to the RPM (load) and the excessive fueling to achieve/maintain the desired RPM causes high EGT's. This is exactly why we take pitch out of the propellers.

And I had a double whammy - overpropped with boost leaks. Since we’re mechanically governed the engine was still fueling to try and reach desired rpm but the turbo wasn’t charging enough air AND we were asking too much of the engine at all rpm.

Even after repropping I had high EGT (although better than before reprop) because boost was down 5psi from where it should have been. Once boost came up the EGT plummeted back to desirable range.

i have to imagine the Fuel to air ratio was then back in the happy zone and we were finally getting proper burn along with increased airflow in and out of the cylinder, ultimately lowering EGT
 
Since I’m on my analog to digital conversion kick I’m curious about rpms. Since removing my grid heaters I realize there was an rpm sensor on the tranny that fed info to the grid heaters. Since this is no longer used I’m wondering if I can tap into this sensor and convert and put this on the nmea2k network. Curious if anyone has done this and is the sensor viable or would I need to replace with something proprietary.

also considering adding a pressure sensor in the raw water loop to keep track of water pressure should there be a failure. I believe garmin has the ability to set alarm thresholds for these.
 
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Since I’m on my analog to digital conversion kick I’m curious about rpms. Since removing my grid heaters I realize there was an rpm sensor on the tranny that fed info to the grid heaters. Since this is no longer used I’m wondering if I can tap into this sensor and convert and put this on the nmea2k network. Curious if anyone has done this and is the sensor viable or would I need to replace with something proprietary.

also considering adding a pressure sensor in the raw water loop to keep track of water pressure should there be a failure. I believe garmin has the ability to set alarm thresholds for these.

Not sure what that sensor does, but I think most of us tapped into the RPM sender for the Tachs. I paralleled my converter with Aetna tachs. Does your analog->N2K converter have a pulse input?

Adding a pressure sensor to alarm on loss of cooling water should be fairly easy. You would have to decide if you want a pressure switch (on/off) or a pressure sender to keep track of actual pressure and alarm on a low threashold.

Im going to do a knockoff of the Tides Marine Smart Seal system. It warns if your shaft seals are getting hot, due to lack of water. I have a Maretron TMP100 Temperature module, with a couple open channels, so I’m just going to add a temp probe to the body of the Tides seal to look for a temperature rise.
 
Installed similar nmea 2k boost sensor from acrossoceans yesterday. So far very happy with the setup. Very easy to install and configure.
View attachment 121428
You are doing all the mods on my list. I would love to see your install of both egt and boost. Are you still at the Shipyard this year?
 
You are doing all the mods on my list. I would love to see your install of both egt and boost. Are you still at the Shipyard this year?
I am. You can swing by anytime once we get in. When are you going in?
 

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