Additional engine temperature monitoring suggestions

[KahuNZ]

I've recently bought a Viking 55 MY with a pair of 8v92TAs in their 750hp spec. They´ve got about 3000 hours each, and appear to have been very well maintained - starting great, making good power, and surveyed well.

I'm considering a wee tinkering project - building a temperature data logging system using a Raspberry Pi and some temp sensors that I could strap to the outside of the engine in interesting points. The main VDO and Murphy Gauge sensors (water temp only) are all working fine. These would just be additional.

Mainly this is just for interest, but could hopefully be of some value in establishing and tracking engine temps over time(?) The sensors would just be fixed to the outside of the various areas of the engine - so will obviously not give accurate point readings, but should be able to pick up on changes over time. The sensors are cheap and small, so I could easily go with a dozen per engine without too much hassle. I was inspired by people who have been using IR heat guns to log engine temps manually - which seems pretty labour intensive and potentially inaccurate compared to what I´m planning...


Two questions -

Would this data be of interest for tracking performance over time? Could it suggest maintence issues before they become major? And could they potentially help with diagnostics or a more detailed engine alarming system - for example a cylinder that was running hotter/cooler than others or a cooling circuit that wasn´t performing right.

Where would you suggest adding sensors? My guessing was -

1. Raw water intake and outputs (to measure the differential and therefore rough performace of the cooling system)
2. Coolant circuit at the heat exchanger intake and output (same idea)
3. Oil cooler intake and output (same idea)
4. Gearbox oil cooler intake and output (same idea)
5. Several on the crankcase in a location that could start detecting if an invidual cylinder was cooler than others (any suggestions for where this might work?)
6. On the turbos, near the oil outlet to approx shaft temp, plus on intake and exhaust sides for rough air temps.

[NBs]

Hi,

I think EGT is nro1

https://official.bankspower.com/tech_article/why-egt-is-important/

NBs

[GordMay]

Greetings and welcome aboard the CF, Kahu'.

Interesting project.

[mvweebles]

Not sure trending data at many points is valuable beyond an interesting science project. But there are two temp sensors that I would definitely recommend.

Pyrometer is definitely a good thing. There are probably 3/8" or 1/2" NPT plugs on your manifolds into which you can insert a thermocouple. Usually before the turbo, but after is okay too. I guess monitoring the difference between the two might be useful.

The second temp sensor would be the wet exhaust temp. This is an excellent early warning of a blown impellor, clogged sea strainer, or other raw water circulation problem. Easiest and least expensive would be an Aqualarm system that triggers above 165-degrees vs giving the actual temperature.

https://aqualarm.net/exhaust-engine-...twin-p-12.html

Every boat should have one yet they are rarely seen.

Peter

[Weatherbird]

I'd put one on the cover for the impeller.

[deblen]

Suggest sensing the water cooled exhaust (hose)temps.
Gives fast warning of blocked raw cooling water. Len

[goboatingnow]

Personally the first thing I add is a flow meter in the intake after the strainer

[mvweebles]

Excellent article by Steve D'Antonio

https://stevedmarineconsulting.com/o...alarms-part-i/

Peter

[Hoodsail]

Weebles, thanks for the link to that article...very helpful...dont have a sensor on my diesel's exhaust, but going to take my infrared gun to the hose at varied RPMs to see what temperature my exhaust is running at...In the Spring, that is.

[KahuNZ]

Thanks all for the very helpful responses - great guidance on what I should be setting up.

Interestingly, there appears to be some sensors in a location that looks sensible for monitoring EGT (well, post-turbo EGT) - but no montiors or alarms related to this as far as I'm aware. The helm stations are very original too, so I don't expect that someone deleted monitoring devices on the helm stations... although perhaps they're linked to an alarm only?

Found an unrelated photo in my library with the suspected sensor in the corner of it. There's a similar sensor on each of the four turbo outlets. Does this look like EGT? (https://imgur.com/a/Gmz4MQi)

[Lepke]

8v92ta continuous rating is 1800 rpm. I'd stop there if you want long engine life. The difference between running at 1800 or max 2300 is double the fuel use and half the engine life.
The EGTs are the first place I'd add sensors on a turbo engine. And then oil temps. I don't think random temps along the block or head will tell you anything except cooling patterns you can't easily change. Detroits will put out almost exactly the same hp in each cylinder. It can be changed slightly by injector or valve adjustments and with different sleeves at overhaul. But a stock engine should be fine.
For all your effort, time would be better spent on timely oil changes and adding a bypass oil filter. Keeping the fuel clean and adding a fuel conditioner with increased lube qualities will make your injectors last longer and give better mileage.

[Pillroller]

Far too many sensors. 90% will read the same on very large lump of cast iron. The above suggestions on coolant and oil pumps might give some interesting readings which, as said, could point up potential problems.
The temp of the oil in the sump, and ergo, the temp of the outside of the case will be consistent, because purely of the bulk of oil and the high distribution of heat by the metal case.
Just my two pennorth.

[more]

Originally Posted by KahuNZ

I've recently bought a Viking 55 MY with a pair of 8v92TAs in their 750hp spec. They´ve got about 3000 hours each, and appear to have been very well maintained - starting great, making good power, and surveyed well.

I'm considering a wee tinkering project - building a temperature data logging system using a Raspberry Pi and some temp sensors that I could strap to the outside of the engine in interesting points. The main VDO and Murphy Gauge sensors (water temp only) are all working fine. These would just be additional.

Mainly this is just for interest, but could hopefully be of some value in establishing and tracking engine temps over time(?) The sensors would just be fixed to the outside of the various areas of the engine - so will obviously not give accurate point readings, but should be able to pick up on changes over time. The sensors are cheap and small, so I could easily go with a dozen per engine without too much hassle. I was inspired by people who have been using IR heat guns to log engine temps manually - which seems pretty labour intensive and potentially inaccurate compared to what I´m planning...


Two questions -

Would this data be of interest for tracking performance over time? Could it suggest maintence issues before they become major? And could they potentially help with diagnostics or a more detailed engine alarming system - for example a cylinder that was running hotter/cooler than others or a cooling circuit that wasn´t performing right.

Where would you suggest adding sensors? My guessing was -

1. Raw water intake and outputs (to measure the differential and therefore rough performace of the cooling system)
2. Coolant circuit at the heat exchanger intake and output (same idea)
3. Oil cooler intake and output (same idea)
4. Gearbox oil cooler intake and output (same idea)
5. Several on the crankcase in a location that could start detecting if an invidual cylinder was cooler than others (any suggestions for where this might work?)
6. On the turbos, near the oil outlet to approx shaft temp, plus on intake and exhaust sides for rough air temps.

best install EGT sensors

[more]

like this guy
https://pysselilivet.blogspot.com/20...sure-boat.html
i use this Home: Silicon Marine but this is not for you

[mickand]

I have exhaust sensors from Borel Engineering, Simple, inexpensive and an easy install.