Typical EGT's?
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I am not too sure on the 4bt, but my 2003 6bt Common Rail cruised at 900-1050, and peaked at 1250-1300 (towing up hills, very limited duration).
The general rule I've always heard was 1250 should be max. (once again, these #'s are for the 6bt)
Factors that can effect the EGT reading: Ambient temp, engine load, intercooled or non, distance the probe is placed from the turbo (pre or post), ect...
I have read the #1 cylinder runs the hottest, so I placed my EGT probe in the #1 cyl. manifold runner. The disadvantage is that if the probe physically breaks, the peices will :nuke: my turbo. I used an Autometer unit, so I am not that worried about it.
My engine is not runnig yet, so I have no #'s for you. I do plan to run a small intercooler to lower the EGT's a little, and make the engine more efficent.
I hot that helps a little
The general rule I've always heard was 1250 should be max. (once again, these #'s are for the 6bt)
Factors that can effect the EGT reading: Ambient temp, engine load, intercooled or non, distance the probe is placed from the turbo (pre or post), ect...
I have read the #1 cylinder runs the hottest, so I placed my EGT probe in the #1 cyl. manifold runner. The disadvantage is that if the probe physically breaks, the peices will :nuke: my turbo. I used an Autometer unit, so I am not that worried about it.
My engine is not runnig yet, so I have no #'s for you. I do plan to run a small intercooler to lower the EGT's a little, and make the engine more efficent.
I hot that helps a little
not that I know of, tate.
Whats the best way to check for those? There's not too many places it could leak...
-overhead charge pipe couplers (Tight, because I JUST had them off)
-aftercooler to 'intake manifold' gasket
-boost gauge pressure tap (know this one is good too)
besides a cracked head, what else could I check, and how?
I'll double check the number today and get back to you.... still, it's definately 1000*F +
-Scotty
Whats the best way to check for those? There's not too many places it could leak...
-overhead charge pipe couplers (Tight, because I JUST had them off)
-aftercooler to 'intake manifold' gasket
-boost gauge pressure tap (know this one is good too)
besides a cracked head, what else could I check, and how?
I'll double check the number today and get back to you.... still, it's definately 1000*F +
-Scotty
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390 Posts
In my Jeep I am getting at 45mph 4 psi of boost and around 800°F at 65 6psi around 1000°F +/- 100°F. At WOT easily 1400°F :nuke: for a very short period. I currently have the Water Charge Air Cooler on the engine plumbed into the engine. I very rarely see the engine temp above 165°F . I have a air to air charge cooler that I am getting it modified so it will fit my Jeep and that should be less restriction and better flowing than the Water Charge Air Cooler. With my turbo upgrades I think the Water Cooler is restricting the intake of air also creating a high EGT..
You can get some PVC couplers, mount it to the intake on the turbo, and pressurize the system up to 20psi or so. Listen for hissing, or break out the soapy water. Wouldn't hurt to back off all the intake valves so you're not dumping air into the crankcase.
I'm not totally familiar with the 4bt's, but if you are at 1200 degrees, you should be pushing more than 5 pounds of boost. Check to make sure your turbo is still in good condition. A friend had an HX40 coked up to the point that it would barely turn by hand, sky high EGT's, low boost, slow to build boost, and would smoke like a frieght train.
I'm not totally familiar with the 4bt's, but if you are at 1200 degrees, you should be pushing more than 5 pounds of boost. Check to make sure your turbo is still in good condition. A friend had an HX40 coked up to the point that it would barely turn by hand, sky high EGT's, low boost, slow to build boost, and would smoke like a frieght train.
I had the same EGT prob with mine at first. 1000-1100 degrees running down the highway at 70 mph on flat ground. It drove me CRAZY!!!
I bumped the timing up quite a bit and it made a HUGE difference! Dropped EGTs down to 800-850 on the hwy at 70. Since then I have added an intercooler which helped some but not as much as the timing.
Hope this helps.
I bumped the timing up quite a bit and it made a HUGE difference! Dropped EGTs down to 800-850 on the hwy at 70. Since then I have added an intercooler which helped some but not as much as the timing.
Hope this helps.
in from the latest trip.
50mph:
4th gear, 3psi boost, 775*F
5th gear, 2psi boost, 900*F
60mph is 1000*F in both 4th and 5th gears.
It's almost like the gauge is off or something.... Pretty much stays around 800*F if I'm driving normally (cruising), and goes up to 1000*F if I accelerate.
Probe is in the manifold, 5/8" up from the turbo flange, in the center of the rearward outlet.
I'll try and pressurize the intake, might be a few days though.
50mph:
4th gear, 3psi boost, 775*F
5th gear, 2psi boost, 900*F
60mph is 1000*F in both 4th and 5th gears.
It's almost like the gauge is off or something.... Pretty much stays around 800*F if I'm driving normally (cruising), and goes up to 1000*F if I accelerate.
Probe is in the manifold, 5/8" up from the turbo flange, in the center of the rearward outlet.
I'll try and pressurize the intake, might be a few days though.
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225 Posts
I also run the cpl 857 and had similar troubles in the beginning. Ive made several mods since but the ultimate problem was a failed air filter that went through the turbo and piled up on top of the aftercooler core. Stopped up the entire core except for one 1 1/4" hole. I had already made some turbo mods before I discovered this but I was amazed at the reduction in temps after I cleaned the aftercooler. You absolutely must separate your aftercooler from the engine coolant; an electric pump, a heat exchanger in front of the radiator, some clear hose, and a small reservoir tank- makes a world of difference. Since then: 12cm turbine housing, 56mm compressor wheel and housing, timing advanced a hair over 1mm, AFC diaphragm maxed, 3/4 turn on star wheel, 1 turn on full fuel screw. My truck weighs a verified 6200lbs, and has aerodynamics similar to a brick. 65mph on level ground is
775*, 55mph is about 650*, max throttle 1100* at 32lbs boost. If I can help more let me know.
Carl
775*, 55mph is about 650*, max throttle 1100* at 32lbs boost. If I can help more let me know.
Carl
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225 Posts
I also thought the aftercooler was a restriction so I drilled/tapped and installed my boost probe pre-aftercooler. No difference in boost readings.
Carl, any recollection on where you got all of your goodies?
Is the pump verified to be a hair over 1.00mm or just a rough guesstimate?
Sounds like you hit the nail on the head as far as setup goes. I'll check the aftercooler for plugging. I've always run a K&N filter on my truck, but that's not to say Frito-Lay did before me.
Please let me know if you remember where you got your stuff from, or if anything can be pilfered from another truck.
Much Appreciated.
-Scott
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1,203 Posts
i run about 6-700 crusing at 65-70 on the highway, goes up to 700-750 when i cruise 70-75. Goes up on hills, but not a whole lot.
this is unloaded at around 5klbs, give or take.
this is unloaded at around 5klbs, give or take.
What the hell???
Stupid Jeep's....
-Scotty
Oh, and I'm still working on that tach for you, dude.
Timing Retarded?
Hey fitty,
The first thing I would check is your timing. Retarded timing will cause those high EGT's. Mark your pump before you turn it though. Rotate it toward the head about 1/16" (from your mark on the pump flange), and then check your EGT's.
Bob B.
Hey fitty,
The first thing I would check is your timing. Retarded timing will cause those high EGT's. Mark your pump before you turn it though. Rotate it toward the head about 1/16" (from your mark on the pump flange), and then check your EGT's.
Bob B.
Update:
Turbo is an H1C, 16cm outlet housing, pretty sure it's the right one, judging by how rusted on the mounting nuts were.
Intercooler is not plugged. just confirmed that. Found a charge pipe hose clamp that might have been too loose, so we'll see there.
Checked the alignment marks on the pump-to-front case, and they're smack bang on, like, artwork that they're that *perfect*. Will try advancing the mark 1/16" tomorrow and see how that does.
Full fuel screw still has the factory collar on it, so I will *assume* that it's 'stock'.
I'll report back and edit this when I get home.
Alright, Home. EGT's are actually a titch lower now. only 900*F at 60mph, maybe lower. Didn't really get a good run on the highway. Temps are down on accelleration as well, only hits around 800*F now.
One down.... back to the drawing board....
Turbo is an H1C, 16cm outlet housing, pretty sure it's the right one, judging by how rusted on the mounting nuts were.
Intercooler is not plugged. just confirmed that. Found a charge pipe hose clamp that might have been too loose, so we'll see there.
Checked the alignment marks on the pump-to-front case, and they're smack bang on, like, artwork that they're that *perfect*. Will try advancing the mark 1/16" tomorrow and see how that does.
Full fuel screw still has the factory collar on it, so I will *assume* that it's 'stock'.
I'll report back and edit this when I get home.
Alright, Home. EGT's are actually a titch lower now. only 900*F at 60mph, maybe lower. Didn't really get a good run on the highway. Temps are down on accelleration as well, only hits around 800*F now.
One down.... back to the drawing board....
Most guys here are running smaller housings to get more boost. That's why your boost is lower and EGT's higher in the same running conditions.
16cm is stock, is it not? Working on getting my hands on a 12cm housing.
60mph, 5th gear, 1800rpm, 5psi boost, 1000*F.
Noticed some restrictions in the intake tract... Airbox to atmosphere opening is 3.25", hose from airbox lid to turbo is 2.25". Turbo inlet is 3" I believe....
Would this be starving the turbo?
-Scotty
No those woudl be fine, it's things like gummed up air cleaners and intercoolers that can cause problems but sometimes be hard to find.
Checked the air filter, and I checked the aftercooler, both are *mint* so i'll try getting the pump bolts loose today and see if I can get it to move that little bit.
Oh, and thanks for all the help so far guys. It's REALLY appreciated!
-Scotty
Oh, and thanks for all the help so far guys. It's REALLY appreciated!
-Scotty
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