Questions about Pyrometer

[Sweetfire]

Had the Pyrometer installed yesterday. Now I'm wondering what most people see as a normal temp. range when running empty and/or towing. Empty, I seem to be between 400 and 500 degrees depending on % of grade I'm climbing and for how long I'm climbing it. Also, how low should I let it cool down to before shutting the engine off? Temp. probe is on down stream side of turbo. Manual with guage advises to avoide temp. over 900 degrees for extended periods. "Extended Periods" seem kind of nebulous.

[DavesDmax]

Well I can't tell you what a Ford runs for normal but, the Duramax in my Chevy will run 600° empty @ 60mph with 2lb of boost. Pulling my trailer, EGT's will run about 750-800° @ 60mph. That is all on flat ground with little wind.

Max recommended EGT's on a duramax is less than 1450° sustained and if kept less than 1300° all the better.

It's nothing for me to spike temps to 1100° on acceleration. My trailer weighs in at a light 6100lbs. My truck is stock with no tuners, intake, or exhaust mods.

idling temp for my engine is about 275° in the winter, 325° in the summer. It takes less than a block for mine to cool back down after a highway run. When pulling into a campground, the EGT's are back down to normal idle levels.

I forget what the name of the Ford diesel web forum is but, they could tell you all the information you need or want.

[patodonn]

Ford folks, hop in!!!

The EGT "limits" and readings depend on the location of the temp probe in the system. If it is before the turbine, it will almost always read a lot higher than if it is after the turbine. In the Dodge I have, the temp probe is prior to the turbine, and the max EGT is supposed to be 1300. I use 1200 as my personal max, and almost never allow it to get above 1100, if I can help it. Towing "cruise" (in overdrive, 62 MPH on level pavement) is 800 degrees and 8 inches of boost. I do have a power chip, and a non-OEM heavy duty transmission which allows use of overdrive on level terrain. My Monty weighs 14,000 lbs when "on the road".

[Montana Sky]

My Chevy will run 750° empty @ 80mph with 8lbs of boost. Pulling my trailer, EGT's will run about 700-850° @ 68mph, this is on flat ground with little wind. Can get as high as 1100° on acceleration or long grade. My trailer weighs in at a light 13,250lbs. My truck is stock with no tuners, intake, or exhaust mods. As far as cool down temps idling temp for my engine is about 250° in the winter, 300° in the summer I wait to 300-350° before shut down. My pyro is post turbo and the mechanic who installed it said under 400° is a safe shut down and keep the top end away from 1250° or higher.

[Sweetfire]

Installer said temps measured on the down stream side of turbo should be 200-300 degrees lower than on the up stream side. I noticed temps were a little higher coming into work this afternoon, around 450 to 600 degrees at 65 to 70 MPH on a 6% to 7% grade 2,500 to 4,343 foot elevation change over a 5 mile distance.

[Champ203]

I can't help with the Fords, but for you Dodge guys if you have a pre-turbo probe the best fuel economy will occur *if* you can keep the temp under 750 (while empty). Info from Turbo DIesel Register website on one of the longer posts I've read on this subject. I'm a failure when it comes to keeping it under 750 (too much city driving). BTW on long pulls the temp difference between pre and post turbo probes can regularly be 400 degrees.....

[Charlie]

It depends on where they installed the thermocouple be it on turbo inlet or turbo exhaust. Mine is on the exhaust and the 900 degree temp is the max. that I should see at this point. Located on the turbo exhaust is not as responsive as the ones installed on the inlet and I have been told that they should see 1250-1300 degrees on the inlet without causing problems.

If the temp approaches the max, drop the tranny in the next lower gear and as RPMs increase there will be more circulation and an immediate drop in temp on the pyro. If you want your turbo to continue to function I would not even consider running past the 900 degrees for any time at all.

As far as cool down, the Ford manual states that when pulling heavy load the engine should idle for 7-10 minutes to cool the oil before shutting down to prevent carbonizing of the oil on the bearings, on mine this relates to 225-250 degrees on the pyrometer.

[5rvers]

I have my EGT installed pre-turbo. I normally run around 600 degrees empty traveling about 60 to 65 MPH and about 5 # of turbo. With the Monty I still run around between 600-900 degrees at 65 MPH. It will go up climbing a long grade but I never let hit 1200 degrees. I let it cool at 300 degrees.

[Lstierw]

I try to keep my exhaust Temp. definitely uner 900 degrees. I watch both the turbo and the exhaust Temp. I can run really fast uphills but do i really want to......Slower is nice....Les

[thook]

Everyone seems to be right on. My Ford PSD 7.3 runs around 500-600 empty and 65 to 70. Pulling my 3400RL it will let it get to 1200 before backing off. My pyrometer is pre turbo.

[Sweetfire]

Cool down temp. on one of our fire trucks is 300 degrees or less but that is on a big, two stroke, Detriot, so I wasn't sure if these smaller engines were similar. Thanks everyone for the feed back.

[ols1932]

Banks Engineering recommends not exceeding 1100 °F. On flat surfaces (relative) I run about 500. In hard pulls up hill the temperature will run up to 900-950 °F. I believe I hit 1100 one time on the Grapevine.

[MuddyPaws]

There is no hard & fast rule for the difference between pre/post turbo readings. In some situations it is as little as 40 degrees, in others it might be 300 - 400 degrees! That's why most folks put the pyrometer probe before the turbo, or even in the exhaust manifold. I've done both and prefer to drill & tap the manifold. It's the temp of the piston crowns that's important. >1600 degrees = melted crowns = about 5 cubic yards of money.

I installed a Turbo Temp Monitor (TTM) which idles the engine until the temp is less than 300. Some set it as low as 250, but at 250 your truck is going to idle for a very long time. The longer it idles the more likely it is to put the computer into anti-theft mode - meaning you'll have to use the key to unlock it.

Going to a 4" exhaust & downpipe will drop your temps, a high flow air filter helps, and removing the pre-heater if you live where it doesn't freeze often helps even more.

Go to www.thedieselstop.com I'm Diesel_Junkie there. But be warned, it will be a very expensive addiction.

[Sweetfire]

I chose to place the temp. probe post-turbo only because the installer recommended it that way. He gave me three reasons for this, I can only remember one right now. That was if the probe were to break off (and I have no idea how likely that is) I didn't want the turbo to eat it, in more ways than one.

[Charlie]

Dennis-
I had mine installed post turbo for the same reason. Don't know why it would ever come loose but there is always a possibility. Also the installer was concerned about any metal shavings that might fall into the intake when he drilled the hole to insert the thermocouple.

As I posted earlier the response is not as quick as one installed pre-turbo but the important thing is you have it and will be able to see what is happening.

[rickety]

Is it really necessary to have a pyrometer on your rig?
I'm asking because I'm new to Diesels and want my Chevy to have what it needs. I normally tow at 60-65, and have neveer noticed any high tmeps to speak of from the engine or tranny.

Many Thanks you guys

[Sweetfire]

Rickety,

I'm pretty new to diesels too. As I've watched the Pyrometer over the last few days I've noticed EGT's that vary from 375-629 degrees depending on conditions. The water temp. guage did not vary at all. I think this is telling me that altough EGT's and engine coolant temp's may be linked the EGT's could increase faster than coolant temps. so by the time coolant temp's indicated a problem it may be too late for the turbo. I also know the tech's that work on our fire trucks are adament about letting the turbo cool down (300 degrees or lower) before shutting down the diesels.

[Charlie]

Rick-
As long a you do not alter the engine you should not have to have a pyrometer installed. Pyro temps are on the turbo and does not have a great impact on radiator coolant temps. I had my gauges installed because I wanted a little more from the motor and installed an 80 HP booster chip to the computer therefore it was no longer under factory specifications and I need visual indication of what it was doing. Only when I hook up to the Monty do I watch the gauges, otherwise I don't worry about it.

[rickety]

quote:Originally posted by Charlie

Rick-
As long a you do not alter the engine you should not have to have a pyrometer installed. Pyro temps are on the turbo and does not have a great impact on radiator coolant temps. I had my gauges installed because I wanted a little more from the motor and installed an 80 HP booster chip to the computer therefore it was no longer under factory specifications and I need visual indication of what it was doing. Only when I hook up to the Monty do I watch the gauges, otherwise I don't worry about it.

Charlie, so even though i have a turbo and it is stock, I really don't have to worry aboutg the EGT Temps? I don't seem to have any problem at all towing the Monty at any speed, or on any grade, I've never had any big temp fluctuations in transmission or engine. Many thanks for the answer.

[pud2]

I run about the same temp empty and around 700-800 pulling on a grade. If i remember right i think the limit was 1100-1150. Mine is after the turbo but i have the banks system also.