EGT probe

[Texas Diesel]

Anyone ever had an EGT probe tip break off and get sucked into the turbine? Should I plug the pre-turbine hole and move the thermocouple post-turbo?

 

[EMDDIESEL]

I cant believe this topic is back. I thought it was dead, now, it has returned. I honestly dont know how the thought of Catastrophic Thermocouple failure got started, but i have never heard of it happening. This EXACT same question was asked awhile back and nobody had it happen. Your Exhaust valves are Pre turbo, do you worry about them failing and being blown into the turbine?, they are moving parts, a Thermocouple is not, so the chance of that happening is non exsistent. I even asked Auto meter if they ever heard of one of there units failing and they said they never did, ever. The only way you thermocouple is going to break is if it is hit by something in the exhaust stream, and anything flying out of your engine big enough to damage the Thermocouple would obviously itself destroy the turbo. The only other way its going to break is if somebody installs it improperly, IE bottoming the thermocouple out to the point you bend and crack it.

Its yet another case of somebody who started a rumor about there paranoia. They use the same Thermocouples in applications that are worth ALOT more then a holset Turbo. They have Thermocouples PRE turbo on $80,000 turbos at my job, do you think they worry?, do you think they would do it if there was even a CHANCE of it breaking off?. Even the highest realistic EGT's would not be enough to melt one, let alone break it off. Its a 6 cylinder diesel, not a Jet engine.

 

[Texas Diesel]

EM, I think your strong feelings on this subject are rooted in your childhood, did your mother ever hit you? Seriously, I never saw this question here before. I was surfing and found a post (not TDR) about a thermocouple fracturing and sending pieces hamlessly through the turbo but it was an industrial engine. The cause was theorized to be thermal fatigue. Not intending to send your blood pressure into stroke zone I was wondering if this was a problem. BTW, they were gonna move the probes post turbo in the remaining engines.

 

[Archive]

EMD... very slowly raise your hands up off of the keyboard. Wiggle your fingers a few times. Now take a deep breath or two!



Actually, you are right and I remember this on a previous thread... just didn't know ya had such strong feelings about it.

 

[Vaughn MacKenzie]

...but to the newbees

EMD, I love your post . But the truth is, what may be a totally battered, dead, black and blue horse to you and the TDR veterans, may appear as a fresh, white stallion galloping free as the wind across the open plains, to the Newbees (sorry to the new folk ). he he he



Vaughn

 

[Bigsaint]

This topic has beaten like a red headed step child, no offense to you, Texas Diesel. If YOU want it pre-turbo, put it there, that's where mine and most of the BOMBers place the sender. There's no easy way to calculate pre-egt's with a post sender, too many variables. IMHO, it's easy to calculate post egt's, just wait till you hit 250 pre-turbo and then you are there. There, wasn't that easy as pure as wind driven snow



Scott W.

 

[EMDDIESEL]

Sorry to seem angry, i really was not, its just that original post had this whole place in a uproar.

By the way, yes, my mother beat me for installing my Thermocouple Post Turbo on my go kart and i have never been the same since

 

[Forrest]

Post EGT potential misconception

There was a calculation floating around that calculated pre turbo EGT based on post EGT readings. Don't use it. I am here to tell you, the safest way to measure EGT is pre!!! My experience was with the HX35-12cm @ 32psi with a 340hp plate. My post readings were 950 degrees. I moved the probe to pre & backed off @ 1500 degrees. Thought I was safe with that post turbo measurement.

 

[Turbo Thom]

Big Saint:

You need to be more careful with your choice of words. I could take offense to your remark. I ain't no stepchild but I did have red hair, although I now have none now, I remember in my child hood my mother beat me and my daddy said he was not so sure he was my daddy. Gosh I must have been ugly. But what you said brings bad memories. Now I might go postal. Try to be more sensitive to us less fortunate. Now I got myself cruing.



Preston

 

[Archive]

Originally posted by EMDDIESEL

yes, my mother beat me

Somehow, EMD, I'm not buying that! But, she may after she sees this thread!

 

[HC]

The only other way its going to break is if somebody installs it improperly, IE bottoming the thermocouple out to the point you bend and crack it.

You got that right - my first one broke off, and it WAS due to improper installation by an experienced mechanic who it turned out was installing his first thermocouple. No big deal, as mine was post-turbo. I use it for cooldown on a mostly stock engine, so I'm happy, but after reading others posts, I'll have to reconsider location if I get into bombing. If I had one already installed pre-turbo, I would NOT move it. The improperly installed one broke the first day, so if yours is still good then don't worry about it.

JMO

 

[Archive]

Originally posted by Turbo Thom

I ain't no stepchild but I did have red hair Try to be more sensitive to us less fortunate. Preston

LOL... I still have red hair... and plan on keeping it awhile!

 

[Doc Tinker]

Is a read haired guy who's now bald still a red head?



WWCD2's exhaust got white hot during a dyno run. They said you could see the valves through the manifold . The truck ran fine afterwords. Maybe the thermocouple isn't neccessary. {hehehe}



Tell me again, why we need the exhaust temperature gauge.



Doc

 

[Archive]

Originally posted by Doc Tinker

Is a read haired guy who's now bald still a red head?



Tell me again, why we need the exhaust temperature gauge.



Doc

Doc... they are useful to scare off the ferd boys. I read a thread on the ford site a long while back that said if you see a dodge cummins with gauges, back off. Its BOMBed! I LMAO.

 

[QRTRHRS]

Let's see. Thermocouple probe breaks off, trashes turbo. Need new turbo. I can see the problem. Which turbo? HX40, Pier's, other. Choices, to many choices.

 

[Bigsaint]

Preston, sorry, didn't mean to offend anyone, please don't go postal



Scott W.

 

[Paul]

I have had 2 thermocouple probes go bad, neither of them broke off.