how to install EGT gauges

BartW

BartW

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www.amptec.be
thanks to good advice on here,
I've got 4 of these,
with the "Blue" version Led display ;-)




just a few questions for the more experienced:

this rusty screw, in the EG elbow, richt behind the turbo EG exit,
is this the best place to install the sensor ?


getting that screw out might be difficult, after 3500hrs getting very hot and cold again,
is there a risc for damage ?
or dropping small particles in the turbo ?

would you drill a hole,
and weld the female SS nut on it (nut is delivered with the gauge)
or would you cut female 1/8 NPT thread in the old nut ?

how to seal the old nut back in the elbow, high temp resistant ?

thanks for practical advice,
 
fwiw, "proper" (as in racing engine tuning) placement of an EGT gauge is BEFORE the turbo, temps drop substantially after the turbo, so ymmv.

However, you don't have a car racing petrol engine, you have four banks in 2 engines, as long as it's placed on the same spot on all four banks, you are going to have comparable values and will be easy to spot the odd one (or two!) out.
You'll just get to know where it runs daily planning and pootling, that's all you need imho.

So, yes, stick it there by all means, I'd drill a hole and thread it for the nut.
Get the engine up and running for a few mins, turn off try to undo, if not run the engine a bit more ;)

cheers

V.
 
Adding to Vas , pre turbo and use pencil magnets like on this vid .See the comments a fair balance.
Big risk of potentially leaving swarf behind - but post turbo location is OK for relative comparison as Vas says

I don’t actually know what I have got -sorry -suspect post turbo as when spooled up at say 1800 range is 560 ish
If the turbo takes a slug of 200 out .Aside on mine the manifold s are water jacketed so you can,t get really near the actual exits - so I reckon it’s post turbo ,judging on the 560 reading

Bolt - ideally remove
You can get various adapter s on line - just need to know what thread the bolt (s) are .

WD 40 or “ plus gas “ over night or a@ least an hour —- try cold 1st
Engine running to warm if cold does not work .

Or leave in situ and just drill using a sharp new bit slowly with lub / coolant .
Thing is the bolt will be harder to tap I think than the casing - but try the bolt 1st
You could run the engine @tick over at the last min when removing the bolt to blast away forwards any swarf
Put an old sauce pan near if flames shoot out and shut it down straight away .

Any manifold gasket sealant from an auto shop will work when re-fitting

https://m.youtube.com/watch?v=S6sMeV1YKVA
 
Portofino said:
Just had a thought Bart , our pipes pre turbo are water jacketed ( unlike a car )
So don,t drill a hole before the turbo .

Bolt - route :encouragement:
Click to expand...

+1

coming to think of it, mine are also liquid cooled. So elbow after the turbo is as good as it gets, unless you want to get one sensor on each non cooled exhaust port manifold :rolleyes:. how many 24??? :eek:
I want to see where you're going to stick all these displays Bart!

V.
 
vas said:
I want to see where you're going to stick all these displays Bart!

V.
Click to expand...

on the ER room ceiling,
and hopefully I can read the values via my engineroom camera

as has been said, the main purpose is the see relative temps from the 4 x exhausts,
and evaluate differences at different rpm.

in case I want to know invidual cylinder temp, I can use the IR gun on the bold head screw on each cylinder head
 
vas said:
I'd drill a hole and thread it for the nut
Click to expand...
Hang on V, you can't be seriously suggesting to drill a hole in a place where metal particles can easily find their way to the turbo blades!
There's only one way someone could do that on my own boat, and that's over my dead body... :ambivalence:

Anyway, I'm 99% sure that there's no need to do that, because there's already a threaded hole (closed with a bolt) somewhere in the turbo enclosure, which is meant exactly to fit the pyro bulb.

@ BartW:
It's a pity that you don't have (I suppose) the original "Protocollo di messa in esercizio" of your engines.
That's a report which an official MAN dealer must have done on your boat when delivered brand new, and I'm underlining "must" because without that, MAN would have declined any warranty claims, so no decent yard (and Canados was well above decency!) would have skipped that test.
But I digress. The fact is, not only I have this piece of paper for my boat (I can send it to you if you wish to see how it looks like), but I also spoke with the MAN dealer who did the test back in 2004.
He explained me that there's very little that they couldn't measure on mechanical engines, compared to electronic ones.
Their only problem is that before spending one hour or so in the seatrial, they had to spend half a day to connect all their tools and gauges to the engines - fitting also bulbs where needed.
EGT is one example, but they also measured all sort of other temperatures and pressures, including exhaust backpressure.
And of course they didn't have to drill any holes to do that.

I have only one problem atm: I just checked my files and couldn't find a pic showing the place meant to fit the EGT pyro bulb, and I will not be back onboard before one month or so.
So, I'm afraid I can't explain you exactly which is the bolt that it's sufficient to remove and fit the pyro bulb in its place, but any MAN engineer should easily show it to you, if you can't wait till I'll be able to give you a more accurate indication.
Just one caveat: what I said is related to a 2003 vintage V8. But I would be extremely surprised if the above wouldn't be valid also for your V12, even if older.
 
P,
Vas and I considered to take out the nut, and only THEN drill and threat in it...

I've send a mail to Ilko,
He'll know if there is a sensor position available in the turbo's
 
Fine, I just understood that Vas didn't see the hole drilling alternative as risky.
Mind, I'm not saying that it would actually create any major problem, but I'd rather not take the chance, in your boots! :rolleyes: :D

Btw, I searched for previous posts on this topic in the meantime, because I had in mind that we discussed this before, and in fact I found this post where I already mentioned what we are now discussing. But for the records, back in those days I was only aware of a threaded hole which in my boat is built into the post-turbo exhaust system, which is yard-specific.
So, my comments were slightly different, because what I just said in my previous post above applies to the MAN-specific side of the exhaust, which is something I wasn't yet aware of, back in Aug last year.
 
Hi Bart, i was lucky with mine. First no turbos & there was a blanking allen key correct size in the flange that bolts to the engine manifold.

It it were me I would have them after the turbos, you don't want a sensor that decides to fall apart being sucked into the turbo:nonchalance:

Remove & drill then tap or weld as you suggest.

Paul
 
Found these images sorting out a few photos and thought they might be useful to show how quick the EGTs change

https://imgur.com/a/zD2ms

I found this para in my notes too about Agglomerated soot particles..
Just to focus on why running ( mostly if you can ) correct EGTs are important.
I guess regular oil changes are a must especially if you run a lot below optimum EGT,s

Remember there’s no gears in boat unlike a road vehicle.

Agglomerated soot clusters are commonly called sludge. Second, only to high temperatures, sludge does more damage to a diesel engine than anything else.
Without oil, a diesel engine runs steel on steel. Pistons rub on cylinders and valve hinges grind. In a matter of minutes, the engine will overheat and seize up. With any luck, the damage will not be permanent.
But, sludge literally, sands down the interior components of a diesel engine. The engine will not typically overheat or seize up immediately. But, the damage created by sludge can be far worse.
 
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