[Fredog]

Originally Posted by Mackman

I thought if it goes to high you grub a lower gear to get the RPM's up higher and that will help lower it. I thought the EGT's get high when your dogging it.

that too, if you lug it, it will overheat..

[sidman82]

If you see it go over 1000-1200 degrees, then it is too high. Yes, higher rpm will help temps stay down, so dogging it up a hill, or chugging the gears, you will see temps rise quickly. After market turbos and wrong applications would be a reason to have temps running to high, and dirty, clogged up air filters as was said in another post. Running prolonged high temps may result in head gasket failure and blown turbo. Stay under 900 and you will be ok.

[Fredog]

Originally Posted by Papa Rick

Can anyone explain what a pyrometer is, how it works, and what is a good range. I have been OTR for 9 years now, but never seen one, but will soon have one in the truck I am buying.

Today Bobtailing it would stay on 3, and once when I went up a hill it went up to 7.5. Gauge goes from 0 - 15.

Thanks!

clipped from: www.stewartwarner.com
Stewart Warner LogoFrequently Asked QuestionsStewart Warner Logo

What does a pyrometer do?

* Pyrometers measure exhaust temperature to verify maximum allowable operating temperature and protect the vehicle's engine from over-heating and potential damage. For example: When hauling a heavy load up a hill, a pyrometer will give a quicker indication of an overheating situation than monitoring the engine cooling system temperature.
* Pyrometers may indicate harmful over-fueling conditions as well. Over-fueling contributes to carbon build-up, lube oil dilution and higher operating temperatures.
* Pyrometers help optimize trim settings in boats in order to synchronize motors.
* Pyrometers help monitor applications with a so-called "dead load" that generate high temperature (e.g. tractors). Exhaust temperature is in direct relation to load.
* Operator response time impacts throttle settings and lag causes wasteful over-correction. An incorrect setting may cause an over temperature condition. Pyrometers help operators maintain optimal settings.
* Heavy duty applications - truck and bus, off-highway, marine - generate high heat. Pyrometers monitor temperature rise in critical high operating temperature environments.

hope this helps

[danj_otr]

My '05 Pete typically runs (ideal conditions) 600-700, when it is starting to show signs of EGR or Turbo actuator problems it will run 700-800. Although mechanics told me that they are useless, you can still tell if something is up once you establish normal operating temps.

[uncleal13]

Pyrometers are of less importance on an electronic engine. The only time I saw mine get over 1,000 degrees was this past winter when heavy snow plugged up the fins on the air-to-air rad.
On the older mechanical engines, if your were climbing a hill and lugged down the engine too low, the pyrometer would start to climb. 950 to 1050 was the engine manufactures recommended limits. Once you started pushing 12-1300 degrees you would start to melt holes in your pistons.

[freebirdrfd]

The boss just changed the turbo on my 60 series Detroit, now my pyro temp is staying at 1500* pulling a empty trailer. My water temp gauge is staying at 180*

[Copperhead]

Also, any restrictions in the exhaust system will cause high EGT temps. That is why I put on a ported/polished/coated exhaust manifold, larger BW 171702 non-wastegate turbo, and Walker Megaflow mufflers on the stacks. On a real hard pull, even on a real hot day, my EGT's will not go over the 750F - 800F range on a 500 hp DDEC IV S60. EGT's have never gone above 900F even on a couple of occasions I lugged it down a little.

[Sundance#1]

A pyrometer shows a temperature range in percentages for your turbo. Its been awhile seens I've used one but when it gets above 10% you need to drop a gear.

[solo379]

Originally Posted by Sundance#1

A pyrometer shows a temperature range in percentages for your turbo. Its been awhile seens I've used one but when it gets above 10% you need to drop a gear.

I have no idea of what you are saying! Can you explain?

[Copperhead]

Yeah, I never saw a pyro that gave temps in percentages. Would like to know more about that one.