What is the max egt's that is safe to run at, I tow 11500 pound trailer up the pass and my post probe hit's about 1100 and will hold until I reach the summit, I have been told that I am safe to 1250 all day long this sounds a little high for all day long

 

I think 1250 would be safe but I would'nt want to be there all day either. the 1100 sounds like a much better number to run for long extended periods, but I would'nt let anything under 1250 worry me to much.

 

I posted a similar thread & was told that 900*F was the max for a post turbo EGT.

 

Your post-turbo EGTs will be 100 to 200 degrees hotter than pre-turbo. I believe 1300 degrees is the max (pre-turbo)and I wouldn't stay there for a long time..

 

I pull 13,000 lbs with a pre-turbo and keep it at 1200 degrees on the pulls. You can pop it up to 1300 but not for long.

 

by pre turbo I assume you mean in the exaust manifold, my probe is in the pipe after the turbo, I have been told that you will get a cooler reading there not hotter, I am looking for the highest reading I can safely run at

 

If this is a POST-TURBO probe as you stated, then you are most likey in real trouble with that engine.
I run a Post & Pre Turbo probe, when I'm towing thru the mountains and the Post Trubo Pyro gets to 800 the Pre Turbo Pyro is @ 1200. I have never hit anything over 900 on the Post Turbo Pyro and the Pre Trubo Pyro was @1350 for about 15 seconds.
So in my opinion if the Post Turbo is @ 1200 then your actual EGT is most likey near 1400-1500 and you are burning that engine up

 

So I e mailed Cummins and asked the question. They answered..."most engines produce egt in the cylinder about 1300 degrees or so", "typcally, trucks measure egt from 2 to 6" after the turbo in the exhaust pipe and at that point the egt will be 700 to 900 degF under full load". They also went on to say "the probe is usually mounted 2 to 6 inches from the turbo outlet. "The probe could be mounted ahead of the turbo, however if the probe ever fails it goes directly into the turbo and cause catastrophic failure".

 

On the 2nd generation trucks, those who have run both pre-turbo and post-turbo probes report that the difference between the probes can be from 200 degF at unloaded, flat road cruise to as much as 500 degF dragging a 5th wheel up a steep grade. If you took the worst case of 500 degF, then you would be seeing 1100 degF + 500 degF = 1600 degF pre-turbo temps! Even if you take a median case of 350 degF difference, that's 1100 degF + 350 degF = 1450 degF pre-turbo EGT.

My thermocouple is mounted pre-turbo, and I use 1100-1200 degF pre-turbo as my long-term EGT limit when pulling our 16,000 lb GVWR 5th wheel (see signature) up long, steep grades.

Your truck, your money and your choice.

Rusty

 

Seems to me that most of us agree.

He is burning up his CUMMINS

 

I think I need to have my guages checked out, the dealer installed them, my truck run's at 500 to 600 just cruzing at 45 mph on flat ground empty and if I go up even the smallest hill it will hit 850 + empty without woring it at all, I did notice that with the paper work that there is a program that needs to be set in the x monitor, maybe that did not happen and it is not calibrated properly, thanks for all of the in put

 

That being said, and from a reliable source, seems to me it would be pretty hard to burn up the engine...a stock engine. Seems like you could run it under full load and not max out the safe EGT limit of 700-900 deg. post turbo.

 

I talked to cummins today, and they have a report from the factory, that they put the 600 on a dyno and that at peak hp and full load the engine is at 1100 and at peak torque and full load it ran at 1100 and all readings were taken 6"after the turbo were they recomend the probe to be(they do not want it to break of and destroy the turbo) so they recomend 1250 for a short time and 1050 for long haul, they told me that since my probe is only 2 " down from the turbo and that the max I have hit is 1050 on a pull that I am well with in the capabilites of the motor so I am not burning it up, plus thye also pointed out that since my water temp never went over 200 that I could not gone that hot. Thanks for the feed back

 

I have both pre & post pyros - Pre goes up way quiker - you can see up to 400 deg. difference but only for a Very short time - then the post starts to stay within 100 - 200 deg difference. So Your not BURNING down your engine. Xford your pyro temps are the same as mine - 550 - 600 deg while cruising empty - but will climb to 850 - 900 deg with added throttle - dont wory about that.