Fitting EGT probes+gauges to diesel (MAN) engines

[Portofino]

Moving on .
Chris what kit are you fitting ?

 

[Scarron]

Interesting discussion..

Lots of relevance for me as I am currently in the process of fitting EGT gauges to my Sabre Ford 320L's

They currently have fully water jacketed elbows/risers from the turbo outlets fabricated in very pretty polished 316 SS. water is injected on the downhill side of the bend then through 5" rubber exhaust hose and straight out of the bottom running surface of the hull with a small fart/burp pipe exiting through the side to allow for pressure equalization at startup and idle speeds.

I agree with Tony Athens, that fully jacketed systems are a disaster waiting to happen so am currently assembling the components to change over to a lagged 'hot' riser and elbow.

Read this and then tell me why he is wrong! Everything you Need to Know About Marine Exhaust Systems

 

[Portofino]

Thx Scarron- when you are done welcome to the sleep easy over the winter lay up club .

Nothing wrong at all . Blatantly obvious to me .

Mapish + any others ……Quote Tony .

“ For those who cannot grasp what the issue is here, a simple explanation – This is a double walled 90 degree wet elbow that was never designed to “hold water” in this orientation but, rather, be mounted horizontally so as to exit downhill and self drain. When installed like this, the sea water that will eventually corrode thru the elbow will now go down the pipe into the turbo or worse. I hope you do not recognize this type of system on your boat!”

 

[MapisM]

You are not selling it to me.
...
What boat is that ^^^ who’s done that ? out of curiosity.

Selling it to you?
When you don't even believe what I'm reporting based on first hand experience?!?
You're having a laugh.
But don't count on me to satisfy your curiosity - or to add anything else, for that matter.
Don't worry anyway, 'cause an Itama she ain't, obviously.
In fact, I'm pretty sure that all those who bought her or any other models of the same builder would rather run than walk away from toys like yours.

 

[Portofino]

Selling it to you?
When you don't even believe what I'm reporting based on first hand experience?!?
You're having a laugh.
But don't count on me to satisfy your curiosity - or to add anything else, for that matter.
Don't worry anyway, 'cause an Itama she ain't, obviously.
In fact, I'm pretty sure that all those who bought her or any other models of the same builder would rather run than walk away from toys like yours.

What boat is it ps ?

Can’t you see what Tony Athens ( Tnx to Scarrons link ) and myself are banging on about .

You do need sufficient headroom in the ER for the dry section to rise though .So I can get the wet jacket thingy if the ER ceiling is too low .How ever that pic you posted of the new ish exhaust claiming it was original has a St Paul’s Cathedral esq ER hight wise .
Madness set up .
Come on play nicely fess up what boats that ?

 

[Portofino]

Selling it to you?
When you don't even believe what I'm reporting based on first hand experience?!?
You're having a laugh.
But don't count on me to satisfy your curiosity - or to add anything else, for that matter.
Don't worry anyway, 'cause an Itama she ain't, obviously.
In fact, I'm pretty sure that all those who bought her or any other models of the same builder would rather run than walk away from toys like yours.

it’s not OEM .
Compare the flange pics of your two pics .
Your boat highlighting red circle .Your short dry bit is MAN white painted .
This V10 not painted note the blots on the actual turbo flange unpainted .

Then the gen over spray particularly around the fresh water injection after the turbo , none what so ever .Yet other pipes have over sprays ( excluding the fresh ge box hydraulic braided hose - that’s recent )

That exhaust despite what you have been told is a replacement like the g box hose .

100;% certain on this .
Blue = overspray.
Yellow no paint esp the turbo flange and it’s bolts + no over spray .



Anyhow as says madness , utter madness in that cavernous ER .

Your boat spot the differences .

 

[MapisM]

Don't stop PF, tell us something more about that boat and her builder.
You obviously know better than myself - after all, I only spent a couple of hours onboard with her first and only owner, so what do I know?
Apropos, that guy was NOT selling the boat when I met him, he showed no signs of mental disorder whatsoever, and had worked for 30+ years as engineering consultant in redesign of chemical plants whose complexity is a multiple of what you can find even in superyachts.
So, since you are so sure that he was telling me porkies about what was done (or not, in the case of the exhaust) on the boat throughout her life, maybe you can explain me also his reasons for lying.
I'm not holding my breath on the possibility to learn something new from you, but as they say, life is full of surprises...

 

[Portofino]

Don't stop PF, tell us something more about that boat and her builder.
You obviously know better than myself - after all, I only spent a couple of hours onboard with her first and only owner, so what do I know?
Apropos, that guy was NOT selling the boat when I met him, he showed no signs of mental disorder whatsoever, and had worked for 30+ years as engineering consultant in redesign of chemical plants whose complexity is a multiple of what you can find even in superyachts.
So, since you are so sure that he was telling me porkies about what was done (or not, in the case of the exhaust) on the boat throughout her life, maybe you can explain me also his reasons for lying.
I'm not holding my breath on the possibility to learn something new from you, but as they say, life is full of surprises...

All I am going by is the pics .Not party to any conversations.
Theres no way from judging from the two pics your own boat and the other with the V 10 the exhausts on the V10 are “ original “

Any body can see that .

With the “ selling “ I meant like Tony Athens says and scarron infered and my seemingly correct analysis re water leak back flow down the riser into a turbo + open E valves .

Why do that ? The only rational is a too low ER ceiling , too low for any meaningful riser / loop above the water line .

BtW speak to Nordhaven about dry exhaust running all over the show .

Modern insulation materials work a treat .Like the stuff in my pics those silver quilted blankets wire on like a ladies corset .

 

[Portofino]

This pic just appeared on the MAN FB forum .
I am posting it to answer one of my inquisitive questions and partly answer the EGT s on a V motor , to settle the one or both banks debate on here .

This is a MAN 1050 from the 90 s retro fit .Crucially it’s got 4 temps , so one on each bank , with a very nice dial smack bang in the middle , live on his dash .How cool is that ( no pun intended )

Guys enquiring as they are a tad high .
Anyhow this is what you guys with MAN V s need to aspire to me thinks .

 

[MapisM]

Guys enquiring as they are a tad high.

Do you possibly know if those temperature are in F or C?
If the former, the numbers are well within specs - and very similar to those of my V8s, in fact.
But if the latter, I would call them through the roof, rather than just a tad high.

I'm saying this assuming that the probes are after the turbo, as it normally happens when retrofitted to these engines.
If before, aside from not understanding where and how exactly they installed the probes, I never came across any comparable data, so I can't judge.
They still sound pretty high, but maybe not as outrageously high as if measured post-turbo...

 

[Portofino]

Do you possibly know if those temperature are in F or C?
If the former, the numbers are well within specs - and very similar to those of my V8s, in fact.
But if the latter, I would call them through the roof, rather than just a tad high.

I'm saying this assuming that the probes are after the turbo, as it normally happens when retrofitted to these engines.
If before, aside from not understanding where and how exactly they installed the probes, I never came across any comparable data, so I can't judge.
They still sound pretty high, but maybe not as outrageously high as if measured post-turbo...

They are F , post turbo .
He’s just had its bum AF d and prop speed applied to the stern gear .
Says they were low 800 s before .MAN techs confirm your “ within specs “ = so all is good ?.

It will be the super smooth props .I noticed a drop this summer after the yard applied this , seems 2 different colours .Sorry I never got exactly it was .It worked the whole season what ever it was .

Gold - undercoat / primer ?
Blue / green = top coat ……what ever it is
But the EGTs were the lowest that i ever noticed and I gained a few extra knots or turned around saved fuel at last yrs cruise speed .Point is the motors had an easier season than previous Imho .EGTs 550/560;*C ….I think pre turbo as OEM .

 

[MapisM]

EGTs 550/560;*C ….I think pre turbo as OEM .

If the numbers of the previous 4 channels gauge are in F, they are fine.
Low 800 F might still be ok at WOT, but it was indeed a tad high at cruising speed - i.e. under 2000 rpm, as in previous pic.

Ref. your Celsius numbers, which are above a thousand in F, as I said I can't judge if they are pre-turbo.
But out of curiosity, do you know where exactly the probe is, and possibly have any photo?
I'm not familiar with inline 6 engines, but in any V engines that I've seen I couldn't figure where to fit a pre-turbo probe.

 

[Portofino]

If the numbers of the previous 4 channels gauge are in F, they are fine.
Low 800 F might still be ok at WOT, but it was indeed a tad high at cruising speed - i.e. under 2000 rpm, as in previous pic.

Ref. your Celsius numbers, which are above a thousand in F, as I said I can't judge if they are pre-turbo.
But out of curiosity, do you know where exactly the probe is, and possibly have any photo?
I'm not familiar with inline 6 engines, but in any V engines that I've seen I couldn't figure where to fit a pre-turbo probe.

Sorry no clear pics ( Yet ! ) but iam pretty sure they are before the turbo on that pic of 20 cm L long pipe between the manifold and turbo .They are underneath tucked away .I will try and get a pic next visit , camera phone width permitting ?
I can change the units to F or C btw on the displays
The manual shows metric units inc *C for temps , EGT s ,oil , CAC air , jacket water etc .
Americans use , feet , inches , gallons ( US) and *F .

They run within spec .Conversation with one of your countrymen’s MAN engineers , seemed happy sub 600*C .running all day
They do rise with rpm to WOT .WOT they like to see an extra 40/60 rpm over rated .IIRC 630-650 *c ??

As I said seasonal prop fouling first and hull fouling to some extent second are the biggest cause of rises in EGTs and the % load increases .
You see it on the displays .

Theres a lot of marine engine blow ups and big bills on forums , injector hosing etc = piston holes .
You never hear this stuff with motor / truck forums running diesels because via a gear box it’s difficult to overload them - vehicles unknowingly.

How ever on marine / boat forums engine bust up seem unusually common occurrences .
Injector pulling almost seems part and parcel of boat ownership routine if you were a 3 rd party glancing forums .
Yet the vehicles do collectively millions of miles / Km s and the leisure boats basically knack all distance wise compared to vehicles yet have a disproportionate amount of injector hassle .

This is because of overloading / excessive EGTs and partly crappy fuel getting through.Although with the fuel angle ,part of the injector tip demise modern leisure boats ( esp CR ) do have robust filtration which is changed out in a timely manor and generally water in fuel alarms .As sensitive as they are with water even more so with CR , the tips are protected from the crappy fuel side .

So what does that leave ?
Fouled stern gear / over weight boats / weedy OEM hp motors ……running round basically overloaded .
The excess heat inside the cylinders burning the injector tips and destroy the spray patterns on boats .
Owner s happy as Larry “ it always cruises at ( insert brochure figure ) knots “ completely oblivious.

If the tips cling on then the valve gear takes a pasting as well .= valve damage and valve train damage from the excess local heat .

All for what ?
For the sake of EGT gauges .

 

[Chris H]

another test is remove the screw and start the engine :
if you flood in seawater, its on the jacket
if you suffocate on exhaust fumes, you're fine it's all the way through...

?

just undo the bolt and push a screwdriver in if it goes all the way in, you're fine. Somehow still doubt it.
and to make things worse, you said there are 4 of these holes in EACH pipe, or one on each?

V.

 

[vas]

you're fine! go ahead.
just make sure you got the threads right and the circa 5mm sensor that gets in is sealed properly most likely with an bronze/brass olive and compression fitting.

 

[Chris H]

I’ve started looking into this in more detail and about to order the silicone marine sensors but noticed they only go up-to 200 deg centigrade, any other options ?

 

[vas]

Chris, 99% these are sensors that fit on the exhaust reinforced rubber hose AFTER the seawater injection, so temps wont exceed 100!
Mind this is only to check that seawater cooling circuit is OK and not buggered and that the rubber hoses wont melt.
pre water injection sensors are different beasts and go up to 1000C (iirc)

 

[Portofino]

Something like this ?
https://www.amazon.com/Pyrometer-Exhaust-Temperature-Sensor-Pickup/dp/B01CTHPQPU?th=1

 

[vas]

Chris, what Porto points to above is what you need.
Only issue is that iirc sender cables CANNOT be lengthened at will with whatever cable you got around. Not quite sure they can be lengthened fullstop.
I v. much doubt from e/r to helm is going to be 1-2m (or whatever it is on offer) Pretty sure routing a cable in your boat is going to be more than 5m
so careful what you buy. Possibly has to be a pyrometer sender on the exhaust, in short distance a black box converting this tiny el. signal to something digital and then the gauge on your dash with normal cabling.
Not sure the one above is as such.

 

[Chris H]

Exhaust Gas Temperature Gauge Kit, 1/4" NPT (EGT)

I will speak with these people tomorrow and see if they do a longer lead, I didn’t want 4 x gauges on the dash but it looks like I have no option, these are 12 volt only ………not sure where I will get that from as everything is 24 volt.

porto’s option is too expensive and I’m not shipping from us.