Turbo EGT Temp

Stu & Filo. T · 10-05-2016, 06:33 PM

Would anyone know what would the egt be on a 8.3 working under load after passing thru the turbo? More importantly to me the temp about 2 ft after the turbo??

milkmania · 10-05-2016, 07:00 PM

I'm still shaking my head that my DT466 didn't come standard with a temp. gauge.

Seems like it would go hand in hand from factory

cadillackid · 10-05-2016, 07:03 PM

did the cummins come with them?
-Christopher

Stu & Filo. T · 10-05-2016, 07:06 PM

Quote:

Originally Posted by cadillackid

did the cummins come with them?
-Christopher

Mine didn't.

Geo Jeff · 10-05-2016, 08:01 PM

I never thought of just moving the EGT down stream if the egt was to hot. problem solved here comes the HP. Kidding

I'm curious why at 2ft. I'm not sure were its suppose to be on your engine but its usually closer and 1000f is max. On my airplane its 4" i think from the exhaust port? No turbo and its gas.

cadillackid · 10-05-2016, 08:17 PM

ive always been told to take it right after the turbo .. though there are some like to see it before to truly get an idea of the in-cylinder temp..

-Christopher

Stu & Filo. T · 10-05-2016, 08:31 PM

[QUOTE=Geo Jeff;165904]I never thought of just moving the EGT down stream if the egt was to hot. problem solved here comes the HP. Kidding

I'm curious why at 2ft. I'm not sure were its suppose to be on your engine but its usually closer and 1000f is max. On my airplane its 4" i think from the exhaust port? No turbo and its gas.[/QUOTE

What I did was remove my entire exhaust & I come off the turbo with a open pipe & at about 2 to 3 ft it turnes up & my 4in exhaust goes inside of a 5 in aluminum pipe that goes from the eng compartment passes thru the interior & exits thru the roof, I have a scoop on top of the aluminum pipe that while moving forces cooling air down between the aluminum and exhaust, I have adjustment screw tapped into the outer pipe to keep the two from touching.

The reason I'm asking about EGT temp is I'm wondering if it's possible for the temp to get hot enough to start melting the aluminum or should I switch to a steel pipe but the only steel pipe I can get would be galvanized & I read that will start flaking off at around 600dg.

SDR76 · 10-05-2016, 08:41 PM

You have double wall exhaust?? COOL!! You should be good, the outer tube will never get as hot as the inner. Aluminum melts around 1200 or so. You shouldn't be getting that high on the EGT. I have pushed a 4bd1t engine to melt a piston, it was at 1400F for about a minute before failure. Look at it this way, your pistons are aluminum too, so it they are surviving, then the heat-shield down stream should also. (even though it is much thinner and likely made of an inferior 2000-series or so aluminum).

Also, if you went to steel, you don't want galvanized. The Zinc will break down chemically before you start seeing it burn, melt, flake or whatever. This will release very bad things into the air (which is likely a life-sentence in prison in the fine Republic of California!) Those chemicals are very bad to breathe. Even here in Utah, where the environment is a disposable commodity, machinists and welders are still very careful around burning Galvanization.

Geo Jeff · 10-06-2016, 02:38 AM

1400 is where a piston melts. After looking at my dt466 turbo it's so close. And such an inefficient set up with log manifolds that if you ran your egt on the down pipe coming out of it probably wouldn't be all that different. But ideally you would run a egt and a gauge on each cylinder. You'll never blow a whole engine up. So you just to to see the hottest cylinder not the blended. The blended is for when everything is happy. Kinda like a oil pressure light. Never understood why it's a picture of a oil can and not a tow truck. Like keeping it full has much to do with pressure when it's run out of oil.
If you want to really control piston melt put a temp gauge on the oil and then the biggest cooler not hooked to the radiator. You'll be able to see in the temp gauge how low the oil is. Almost every engine is over heating the oil. Car manufactures love it. Until you buy a Porsche or high end sports car you never see oil gauges. Then all of a sudden you see them make it 12 or 20 quarts and big coolers. Ferrari and Porsche are great examples. On your bus for a poor mans fix mount a 5 gallon propane tank under it and plumb your oil cooler lines to it. One in and one out. Solder in a radiator metal drain plug to chAnge it. Make the lines go in from the top so it can't drain back and over fill the oil pan. Put a pick up tube on one line to the bottom for seperation of fluid temps. Now you have a huge surface area for cooling 20 extra quarts which will let you extend oil chAnges by 4K or more miles. If you use a centrifuge then multiply that oil change by probably 5 times. 30k or more miles.

Works as well or better on transmissions. The radiator won't be heated by oils any more. The piston oil sprayers are now cooling the piston with much cooler oil. It must make the radiator 30 to 50 more efficient not heating it with the engine and atf oils.

Cheap to do you can solder the fittings in a new propane tank yourself. Or a radiator shop will do it. Brass Or and steel fittings all solder. Built a lot of veggie tanks by drilling holes in stock steel Ford tanks and shoving Cooper tube through them and soldering it all up to have a heated tank.

it really helps for those that don't use turbo timers to shut down the engine after the turbo has cooled properly. But running them 5 minutes is always the best to keep the oil from cooking to a crust on the center bearing and scratching it or plugging it and just destroying the turbo.

Just some options for the DIY guys not wanting to buy expensive external fan driven coolers. You have to go to the source of the heat and control it to manage and tune the rest of the system.

cadillackid · 10-06-2016, 07:17 AM

I love the idea of ballasting for fluids...

when I bought my most recent bus I was told the the 7.3 has the tendency to get warm easily because of the small radiator and usually worn out fan clutches.. so i left my heater valves open for the whole trip.. this gave me an extra 4 gallons or so of coolant that on any hill would have to heat up also ...

I dont have a pyro on either of my busses but am thinking of putting one in... I think my new bus i can read it out on the computer as i believe it has built in pyro.. I'll be hooking to the computer again on it probably later on today and will see what all parameters I can read Live..

so on my DTA360 i should install the pyro in the down-pipe just past the V-band?
-Christopher

Tango · 10-06-2016, 08:25 AM

Lots of discussion on the EGT location over on 4BTswaps.com by pretty knowledgeable folks. Some are installing it right on the turbo as I recall.

cadillackid · 10-06-2016, 08:31 AM

ive seen all kinds of discussions too.. and trying t figure out whether I want to measure EGT before of after the turbo.. to me if im looking for cylinder temps id want to be closer to the engine than i would past the turbo...

on the DT its easy to put it in the manifold right before the turbo.. the turbo is pretty easy to take off so id remove it and install the sensor as to make sure all the shavings were out from drilling.. I have heard of using vacuum and oil andsuch to help keep drill shavings away from the turbo but im not sure I want to risk it..

going in the down-pipe of course is easy.. drill a hole, tack a bung on and screw in a sensor..

-Christopher

Tango · 10-06-2016, 08:42 AM

One trick I recall from the aforementioned site to keep shavings and such out was...(believe it or not) ...drill it with the engine running. According to the source, it blows everything back out. But you have to get the hole nearly through before cranking it up or it's just too danged hot to work on. Same routine when tapping the threads.

Booyah45828 · 10-06-2016, 08:53 AM

Whats the point of a sensor if it's not reading accurately? Most pyro's that I've seen installed have been in the manifold, before the turbo. I'm not sure what kind of data you'd be looking at 2ft after the turbo, but I have a feeling it's not as accurate of a reflection of cylinder temp that it would be if it were in the manifold.

SDR76 · 10-06-2016, 10:29 AM

Quote:

Originally Posted by cadillackid

so on my DTA360 i should install the pyro in the down-pipe just past the V-band?
-Christopher

That works. It's more accurate to be in the manifold, right before the turbo. The pro to this is more accurate reading. Con is IF the probe breaks, no more turbo. Going down stream will just "read" a cooler temp than you actually are.

Booyah45828 · 10-08-2016, 11:02 AM

Quote:

Originally Posted by SDR76

That works. It's more accurate to be in the manifold, right before the turbo. The pro to this is more accurate reading. Con is IF the probe breaks, no more turbo. Going down stream will just "read" a cooler temp than you actually are.

Not just a cooler temp. Exhaust temp after the turbo will vary based off of turbo efficiency. Meaning you could get a false positive while the actual temp is in the danger zone.

I don't know if I've ever seen a probe that was installed properly break off and eat a turbo