Fitting EGT probes+gauges to diesel (MAN) engines

MapisM

MapisM

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For those interested in a bit of background, the issue was already debated in this thread, more than one year ago.

In a nutshell, in that occasion Latestarter explained us the importance of monitoring the exhaust temperature, which can be, in his words, "the diesel engine killer" - particularly on planing boats, which for several reasons are more prone to potentially overloading the engines, hence raising the EGT.
And this is true for any diesel engine, which is the reason why I enclosed "MAN" in brackets: mechanical MAN engines are what I'm interested in at the moment, but the matter is not restricted to them.

Now, with modern electronically controlled engines, this is actually a non-issue, because EGT is one of many parameters constantly monitored, triggering an alarm if and when necessary.
So, all of you folks with these marvels of engineering inside their e/r don't need to bother about this thread.
Yes, you will suffer some electronic faults occasionally, which can only be fixed at ridiculous costs.
And it's not a matter of if, just of when - but that's another matter altogether... :rolleyes:
Ref. EGT, you can just check it in your displays, albeit possibly hidden somewhere in their multiple pages.

For the rest of us, the only possibility is to fit some pyrometer exhaust probes right after the turbos, and connect them to some gauges in the dashboard. No big deal in theory, and in fact Latestarter in that old thread also suggested a US website which sells this stuff at rather reasonable prices.
But I just re-checked the website, and I could only found a US phone number, without any mail address.
Not the most convenient way to get in touch, check the correct material and place an order, 'fiuaskme...

So, I thought to raise this matter here, just in case anyone has already done this job and/or has any ideas/suggestions about who to get in touch with.
Many thanks in advance for any suggestions!
 
You want this fella, shows boost and EGT

https://www.sbmar.com/product/smx-marine-boost-pyro-turbocator-gauge-kit/

Not only that, its called a Turbocator, I mean, really, that is a cool thing to have on the dash!


Latestarter also said, the life of a diesel engine is directly related to the oil change interval (in turbo development as I once was, we looked at all the white papers on the subject of oil borne soot and the affect on bearing life, as part of the task of selecting bearing type). He also said, a good measure of life is total fuel burn, I know the CAT ACERT ECU records this, I guess others do too)
 
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They are IMHO the most usefull guage on the boat .
On screen 4 of the MMDS -Man Management Diagnostic System along with L/hr and load % .

It amazing how the load and EGT ,s and somewhat L/hr change --go up with fouling AND displacement .
Yup fully fuelled and watered + max pax .
Interesting also to see them drop (after full liquids ) as you progress on a long run ,mini trip as the Kg,s shed , props kinda self clean a bit more and the hull kinda smooths -after being perhaps parked up for a month ?

Mid 500, s to just over 600 if I gun it ( upwards of 35 knots ) -mostly with clean props /bottom 1/2 ish fluids @27 knots
580 degrees 1770 ish rpm -sweet spot . Load low 80 ,%
 
simonfraser said:
you must have been reading my mind :

https://trickettmarine.co.uk/nbsp-12v-single-engine-alarm.html

i dont want a guage which i am unlikely to monitor 24/7

just a LOUD alarm will do, at what Temp should it go off ?
Click to expand...

No ---- that's the whole point of monitoring EGT to keep it below manufactors recommendations .
Especially usefull when you return after a few weeks or month or so of it being in the marina --therefore fouled .
You can see how safe to go ,the if necessary plan the prop scub or if uk lift n power wash .
If you ignorantly ( in a true sence ) have no idea or think you can,t be bothered £/€ wise to clean the sterngear and hull if UK ---AND push those throttles fwds "tight wire " cos the salesman /brochure said X knots --then you are slowly killing your engine starting with burn,t turbo tip vanes ---low boost --if Volvo Penta K series or D series outdrives , hunting as the revs drop and the supercharger s kick in ( where fitted ) .
Forums full of this kinda stuff boats on the edge --by that the power /weight ratio /and drag when new and shiney and low on cruising stores just manages to reach say WOT 30 knots or what ever .

Basically they tell you when it's time for a prop clean or if you boats too heavey for the engines .
You know bigger tender , gyro , extra tankage , hard top , jet ski , ---etc etc

Before you get a big bill .

Or just accept low ish cruising speed ,but nice to know what that is ? To keep EGT,s sub 600 degrees .
Additionally around 550 degrees is optimal in terms of correct burn temp to get the best fit of the rings and the correct combustion of the diesel and minor oil residue to produce the least damaging substrates .
Substrates meaning acids etc which accelerate wear and shorten the life span .
Hence idling the EGT drops to 250 , loads of crap produced potentially damaging .
Also after a prolonged D speed say 800 rpm ,low EGT,s sub optimal 550 --hence near the end a good 1/2 hrs of 550 -+ to burn the accumulated crap -cos of tooooo low combustion temps Italian tune up etc .
Best Allways run em at design rated rpm for that boat , keeping EGT,s 550-600 degrees .--well with MAN .
With others ck ,I think CAT run hotter for example .
 
simonfraser said:
you must have been reading my mind :

https://trickettmarine.co.uk/nbsp-12v-single-engine-alarm.html

i dont want a guage which i am unlikely to monitor 24/7

just a LOUD alarm will do, at what Temp should it go off ?
Click to expand...

that's slightly (or rather completely!) different thing. That's for when your water supply to the engine fails.
If the impeller and all that are working fine, you can STILL blow your engine due to EGT and your dash light will be still green...

cheers

V.
 
tnx guys, all helpful.
boat on a trailer, so clean all round, allu prop.
KAD 44EDC, new impeller, tappets just done.
but an old engine, no sign of overheating / low oil pressure / turbo hunting.
i've not taken it above 3000 revs as its old.

should i run it at 3000 revs for 30 mins at the end of every trip, and allow for cool down and not worry any further, as a catastrophic cooling failure is not going to be caught in time anyway ?

or get an EGT monitor, if so, what to buy ?
 
answering the original Q by P.,

where would you put all these gauges P? F/B? do you have space for them?

part of my arduino project list is to built a device for monitoring the EGT on the two engines, plus the raw water flow on them.
That could be done with approx 60euro worth of h/w for the arduino and EGT, raw water flow is a bit complicated so probably another 2 thermistors and a check after the mixer on the elbow would be enough. Get the N2K socket the box and a stabilised power supply (just in case) and we are still under 100euro.

All that will be converted to NMEA2000 and pumped down the bus. Mind there's full support on the N2K protocol for various such things, so you're not reinventing anything, and plotters have ready configured gauges for all that carp. Then it's a matter to setup an alarm on either the GPS plotter, or a small multidisplay device either on the f/b or down below (or preferably everywhere!) so you can hear it no matter it's a pedal to the metal or a relaxed cruise with something blocking the raw water intake.

I've done the prototyping, but over the last few months had no time to play with arduinos and seems that I've burn various bits on a few of them with silly tests, so got to order a couple more...

Assuming it's not a great hurry, I can have something running in a couple of months and will report.
Problem is that I'm fully Garmin so will test and make sure everything works there, dunno what's happening with other brands...

cheers

V.
 
Sorry folks, I'm a bit late in following up, after throwing a rock in the pond.
A lot of interesting suggestions, anyway - many thanks!
Following the order of your replies:

@Farsco: it has been somewhat clarified in the following posts already, but what you are suggesting is meant for a different purpose, i.e. protecting a wet exhaust from overheating, if for some reason the sea water flow is reduced.
It does have its purpose of course, but EGT monitoring is a different chapter of the book...

@BartW: Hi B, are you sure that you need to weld a threaded bushing to install the probe? In my DP, there's a small (1/4 inch, I believe) threaded hole right after the turbo, in the dry part of the exhaust, which is suitable for the installation.
My understanding is that in the old days, MAN asked boatbuilders to include that in the exhaust flanges in order to be able to check EGT whenever necessary, even if the boat didn't include that in the dashboard (which in fact I've never seen on any non-electronic engines boat). So, I would be surprised if Canados didn't follow MAN recommendations in their installations. Or was the exhaust system replaced in the past, maybe?
Anyway, thanks for the hints. I wasn't aware of the Wema stuff, but their probe is too large for me, with a 3/8" thread.
The VDO stuff is instead perfect on paper - and in principle, it would be nice to use VDO gauges, because that's what I already have in the rest of the dashboard.
If you would decide to install the same kit on BA, maybe we could arrange a combined purchase and try to get a bit of discount - with one probe+gauge for each cylinders bank, that means EIGHT of everything, for our two boats together... :)

@ burgundyben: yup, having also the boost pressure would be nice - I'm just unsure about if and where I could attach the boost tube... Besides, I might struggle to find enough space on the dashboard for four of those 3" gauges. Worth considering anyway, thanks!

@ Portofino: interesting reference numbers, thanks. I wish I could make a comparison!

@ Surfacesub: not sure about what you were suggesting in post #6. In that website, a search for "exhaust" pointed me only to the unit in this webpage, which looks very much oriented to automotive/petrol applications - though maybe the components as such could work just fine also for boat diesel engines, no idea...
Otoh, the CruzPro stuff looks more solid, on paper.
Do you have any first hand experience with either of these components?

@ simonfraser: see my previous reply to Farsco.

@ Vas: you always manage to surprise me with your lateral thinking.
The solution you are envisaging is extremely elegant and efficient in so many ways, that I'm sure it could be interesting for many others - on top of myself, goes without saying!
And nope, I'm not in a great hurry, and even if I were, I'd rather wait for your results before doing anything else.
Thanks in advance for keeping us posted! :encouragement:
 
MapisM said:
@BartW: Hi B, are you sure that you need to weld a threaded bushing to install the probe? In my DP, there's a small (1/4 inch, I believe) threaded hole right after the turbo, in the dry part of the exhaust, which is suitable for the installation.
My understanding is that in the old days, MAN asked boatbuilders to include that in the exhaust flanges in order to be able to check EGT whenever necessary, even if the boat didn't include that in the dashboard (which in fact I've never seen on any non-electronic engines boat). So, I would be surprised if Canados didn't follow MAN recommendations in their installations. Or was the exhaust system replaced in the past, maybe?
Anyway, thanks for the hints. I wasn't aware of the Wema stuff, but their probe is too large for me, with a 3/8" thread.
The VDO stuff is instead perfect on paper - and in principle, it would be nice to use VDO gauges, because that's what I already have in the rest of the dashboard.
If you would decide to install the same kit on BA, maybe we could arrange a combined purchase and try to get a bit of discount - with one probe+gauge for each cylinders bank, that means EIGHT of everything, for our two boats together... :)
Click to expand...

there are some threaded holes in my MAN's exhaust right after the turbo, but iirc much bigger than 1/4",
I mentioned about the VDO sensor including bushes just as general info...

that VDO webshop is in holland, last year I"ve ordered there light bulbs and water temp sensors, and that went all smooth, but fairly expensive.
I'll keep you updated when we go on with this plan, (probably coming winter)
 
It's the EGT before the turbo in the manifold that's the one that the modern electronic MAN measure and most usefull ,it's what I,ve been reffering to .
After the turbo is more for protection of the exhaust hose /pipe and in some cases I think what VAS was meaning is an indication of lack of water flow .All this is something different as the turbo can take a lot of heat out of the gas .

For overloading management and prevention of burn,t tips * you need to see EGT before it enters the turbo .

* your turbo may be bomb proof but the exhaust valves and seats less so .
 
Portofino said:
It's the EGT before the turbo in the manifold that's the one that the modern electronic MAN measure and most usefull ,it's what I,ve been reffering to .
After the turbo is more for protection of the exhaust hose /pipe and in some cases I think what VAS was meaning is an indication of lack of water flow .All this is something different as the turbo can take a lot of heat out of the gas .

For overloading management and prevention of burn,t tips * you need to see EGT before it enters the turbo .

* your turbo may be bomb proof but the exhaust valves and seats less so .
Click to expand...

Never knew that!
 
I think there's a bit of x purpose here
Two camps
EGT,s after the turbo to make sure the halyard type exhaust pipe does not melt .

And EGT,s before the turbo to manage overloading from fouled props ,know when to back off .

The pyrometer probe should be installed in either an exhaust manifold or the turbocharger up-pipe. It is not ideal to install a pyrometer probe at the turbocharger downpipe, as the exhaust gas temperature at the outlet of the turbocharger is always less than, and in some instances significantly less than, the temperature at the turbocharger inlet. This is do to the fact that a turbocharger is a waste energy recover device - as the turbocharger converts the engine's waste heat on the turbine side into pressurized air on the compressor side energy is extracted from the incoming exhaust stream, thereby lowering its temperature at the outlet due to the conversion of energy across the turbine. It is therefore only beneficial to know the temperature at the inlet of the turbocharger.
 
I'm afraid I must disagree completely, L.
The cross-purposes (if any) is between measuring the temp inside the WET section of the exhaust vs the DRY section - the former being meant to protect the rubber sections of the exhaust from melting, while the latter is meant to protect the engine.

But before or after the turbo is not so relevant, as long as we are talking of exhaust gas alone (i.e. DRY).
Just re-check the thread I linked in my OP - here's a small abstract taken from a post of LS1 (AKA the diesel engine bible):

"EGT turbine out has long been held as industry standard for measurement. As I stated there is always a small opportunity to insert type K thermo couple in dry section after the turbo but before water injection.
Reason for not measuring at manifold is that there can be a significant variance of temperature dependent where in the exhaust manifold sensor is located."

Btw, I'm not 100% positive about this, but I do believe that the EGT data reported by MAN MMDS displays is also after, not before the turbine.
 
Btw, I'm not 100% positive about this, but I do believe that the EGT data reported by MAN MMDS displays is also after, not before the turbine.[/QUOTE]

I have a parts manual on the boat .We not on the boat ( just had 4 weeks ) .When we return mid Sept I,ll check the schematics .
I understand they had developement issues perfecting the sensors -material and as you infer location .
The turbo is approx 30 cm away from the end of the manifold tree though so,s there plenty of room to place a sensor in that part and still be upstream so to speak .
 
PF,

generally agree with the before rather than after the turbocharger, from my car tuning days, there was a reluctance to fit K-thermocouples before the turbo as these things are not that robust (at least they weren't 20+ yrs ago) and tuners prefered to fit them after, and just compensate on values based on empirical data (and a rolling road session with wideband lambda sensors et al)

And true to that, I managed to destroy the first thermocouple I fitted to my exhaust elbow as the compression thingy around it was plain silly and wouldn't seal. Got to devise another way of fitting them (I've got another 9 to play with :D )

of on the boat till the w/e, so no further replies from me.

cheers

V.
 
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