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texas503

Normal EGT?

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I recently changed injectors to 5x0.010, the truck runs great, but I had a question as to what EGT is normal for these trucks. This is what I have.1997 2500 auto 4x4; #0 plate full back (as in toward the cab); 3.55 gears; 265/75/16 tires; ranch hand bumper; AFC full back; Starwheel full forward I think that is all that would affect EGT.My EGT doing about 55-60 when climbing a relatively small hill will rise to 800 degrees easily and sometimes 900 without me accelerating. I will be doing about 7-8 psi of boost and EGT will climb rapidly. Just under normal acceleration... taking about 30 seconds to reach 60mph, egt will reach 700-800 degrees. Doing 70mph EGT will run about 700 degrees on flat and 800 up a hill pushing 10 PSI.And I have done a boost leak test.Is that normal, just seems a little hot for normal driving? It has been about 100 degrees around here, does that really make a difference?Thanks

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Those injectors are actually a tiny bit under my stock 215 injectors (5 x 0.01025) so I wouldn't think that would be the culprit. You are running a little hot for an unloaded truck. But you have an auto which is geared higher meaning lower RPM's than me at a given speed. RPM pumps out heat, so if you are running (guessing here) 1800RPM at 70, then thats much lower than my 2100RPM at 70... I have a lot of RPM because of the gearing and small tires giving the engine a lot of leverage so it barely breaks a sweat. The bigger tires on yours will also add to the load, raising EGT's. I actually started a chart for this for someone like yourself. You might find it helpful. http://forum.mopar1973man.com/threads/3076-EGT-Figures-for-Reference

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Well I just drove up a local road that is pretty steep and winding, speed ranges from 30-45mph up for about 4 miles. I am kind of disappointed in the power and EGT of my truck. I was running up to 1000 degrees unloaded, except for 6 people crammed in the cab, with about 5 -15 psi of boost. I had the tranny locked-up in 3rd. The 1000 degrees came when I was down about 1200 rpm, but most the time even doing 45 mph the egt was 800-900 degrees. It just doesn't seem like I am building enough boost for the egt climbing. What could be the reason for this? The truck was not blowing smoke except when I was pushing it in the low RPM.I know it is hard to give advice when you really can't see what and when the truck doing. I just expect more, I had more from the lightly modded 24 valve truck. I am glad that I don't have the problems that I had from the 24 valve.Thanks

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If you lug it, EGT's will go way up because the engine is not "pumping" any heat out. You are putting a lot of fuel to it to try and get it to go at 1200RPM but it is a lot happier at 1600+RPM, it isn't designed to lug that low and therefore you just dump more fuel to it and it just builds more heat than it can get rid of. 5-15psi sounds about right though. It takes a lot of fuel at low RPM to build any boost because again you aren't pumping much air or heat so you have to put in a lot of fuel to get more heat which expands the air more making it "bigger" and is then enough to drive the turbo, somewhat. I'll make a video for you today so you can compare and maybe tell me how your's is different and that will give us some clues possibly. You haven't really mentioned anything that would cause higher EGT's. Actually there is onee thing... If your timing is really retarded it will run great, but won't have the power and EGT's will soar. It would cause really good power down low but would fall on it's face up higher. I know you were seeing 1000F EGT down low but again thats just the nature of lugging it, I assume it felt like it had more power down low than the 24V and fell on its face over like 1500RPM?

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First, I really appreciate all your help.The 24 valve I had had better power throughout the whole rpm range. I did have RV 275 injectors and a timing box though. That truck pulled the same road with ease, although I did not have an EGT gauge on that truck.This truck has O.K power in higher RPM range, so I doubt timing is the issue, if there is really an issue at all. I don't know. Could a waste gate stuck open cause the issue.

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Well I just took mine out and although it's 2wd and a 5spd, it should be close enough. But I as only seeing 550F at 2psi up a 6% grade in 4th (same as your 3rd).

http://youtu.be/z60h_zGsOqU

The timing thing won't be obvious, but high EGTs and crappy power are all signs. But, this is starting to sound like something else. I have gone up some 15% grades at 1200RPM in 4th and was seeing maybe 800-900F. So either that hill you were on was a lot steeper than 6% or something is wrong. You say it runs perfect though. Does it smoke anytime?

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Just looked at road grade and it was a 7 mile climb of 6-7 %.

- - - Updated - - -

It smokes if I get on it but clears quickly. It just seems as though it takes a bit to get the truck moving.

How hard is it to put a video on here? I might could do that to help, if it is not too complicated.

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How hard is it to put a video on here? I might could do that to help, if it is not too complicated.

Just upload the video to www.youtube.com and then come back here and smack the (Film Strip Icon) in the tool box and in will ask for the URL of the video. On Youtube you want the share button and copy that URL.

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I do have another observation. See if this makes sense. If I really get on it, say near WOT, EGT don't really pass 1000 degrees, but boost comes up to around 30psi. It seems as if I am just taking it easy getting up to speed or climbing a hill EGT climbs much faster than if I am tearing around, which doesn't happen often. I think the EGT issue is more a, not building boost soon enough, issue. Does that make any sense? I noticed last night as I was driving home from work that doing about 55-60 EGT would go from 600-700 without hardly changing any boost pressure. Could a leak in the exhaust manifold do this? I will see what I can do about a video.

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All of your boost number sound fine. If you can hit 30psi with the fuel plate fully back then that really says your turbo and plumbing is fine. You can only hit 1000 because of that fuel plate being where it is. Let me keep thinking about this.

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I know video will help, but it will probably be late in the week before I can get it. ThanksI did another boost test last night, but didn't find any leaks. Thanks

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Thinking about it more and more I think I have a wastegate issue. What is the best way of checking this? I think it may be opening at around 4 psi, or maybe it is staying cracked open partially. I can make 4 psi of pressure easily, after that egt get much hotter and harder to build boost. I am going to try plugging the wastegate line first.

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Well if you want to check you can just take some air pressure and put it on the wastegate line that goes from the diaphragm all the way over the engine to the AFC. The diaphragm should go in and out. If you have a regulator you can set it at 20psi which is about where it should be opening. Yes that means if you aren't building 20psi, it should be shut.

http://www.youtube.com/watch?v=4JXCO49H0Vk

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Well you were right, checked wastegate and plugged it off. Gate was closed hard with no pressure, and plugging it off did little to no change.The truck was a Cali. truck with egr, but it does have a normal intake horn, the exhaust manifold has been capped off. Do you know if the Cali. exhaust manifold might have a restriction? Will be getting video this weekend.Thanks

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Jesus! and thats unloaded? That actually looks completely normal....IFFFF it had a big trailer behind it! Your numbers at 70mph sound somewhat normal but down low that is just not right. It would be something if one gauge or the other was high but when the boost is way up and the EGT is way up just going up a little hill unloaded, it means it's dumping a ton of fuel into it for some reason. Something is dragging it down causing it to work a lot harder than it should. Just to be sure though, how does it start in the morning? How does it start when it's around 30F or below? What kinda MPG does it get?

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Unloaded I am getting about 18-20 mpg. It starts O.K. in the morning with little to no haze. It idles a little low around 500rpm when first started, but I have the idle set at about 900 rpm due to the torque converter I have pulls it down alot. As far as starting when it is cold, it hasn't been cold here yet since the injector change. Before the injector change you helped me with a lack of low end power and haze problem, and it was hard to start when it was cold with the old injectors. Since the new injectors, the low end power is better, but not great, but I do have high EGTs. I don't remember what EGTs were with the old injectors, partly because I really didn't have a enough low end power to pull something like that. Also some of the old injector issues began after timing was changed. So I am kind of at a loss. I should have just left it alone.

This is how the truck is set up, except for a full replacement ranch hand bumper that weighs about 250 lbs or so.

Thanks

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That all sounds pretty normal but it's normal for a loaded truck... I don't understand what is loading it though. A dragging brake or something would be a very viable issue. I just can't think of what the engine could be doing to simulate perfectly what a load does to it, without there actually being a load.

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Truck rolls too easily to have a brake dragging, although I will check each wheel. I will suggest some hypothetical reasons for my problems and tell me if I am crazy. I will also try to load a cruising video, not on a hill.Exhaust turbine is damaged in turbo, causing it not to spool very well unless large amounts of heat/exhaust flow hit it. Intake turbine seems fine with little to no end play.New injector/s is bad, not creating an effective spray pattern/ dribbling fuel. ( in my 24 valve I had a bad injector/s that caused huge amounts of black smoke under load, no power, and no boost- changed injectors and vast improvement in power and milage) is my reasoning behind thisCould the fuel plate being all the way back be doing something causing load?Could exhaust manifold be plugged?Could timing being too high/low cause this? I seem to have had several issues after timing change, could too much timing cause high EGT. I may be paranoid, but I requested the timing change at the diesel shop to 15 degrees, when I got my ticket it said "incease timing 15 degrees per customer request", I questioned the shop manager about this and he said it was only taken to 15 degrees. I then had the timing checked at another shop who checked it with timing light attached to the #1 injector line, they never pulled the injection lines, they said it was at 15 degrees. The truck does have a lope when dropped into gear when cold, no lope once warmed up just a little.Could valve lash being out cause this?You were pushing like 2 psi at 500 degrees, I don't build practically any boost until 600 degrees. I can also be running along at 55 at 600 degrees with 4 PSI, hit a small hill, go up to 700 degrees and not have boost change at all. What do I need to take loose to see the exhaust turbine to inspect it?Sorry about dragging this on, but I really appreciate the insight.

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Truck rolls too easily to have a brake dragging, although I will check each wheel. I will suggest some hypothetical reasons for my problems and tell me if I am crazy. I will also try to load a cruising video, not on a hill. Exhaust turbine is damaged in turbo, causing it not to spool very well unless large amounts of heat/exhaust flow hit it. Intake turbine seems fine with little to no end play. New injector/s is bad, not creating an effective spray pattern/ dribbling fuel. ( in my 24 valve I had a bad injector/s that caused huge amounts of black smoke under load, no power, and no boost- changed injectors and vast improvement in power and milage) is my reasoning behind this Could the fuel plate being all the way back be doing something causing load? Could exhaust manifold be plugged? Could timing being too high/low cause this? I seem to have had several issues after timing change, could too much timing cause high EGT. I may be paranoid, but I requested the timing change at the diesel shop to 15 degrees, when I got my ticket it said "incease timing 15 degrees per customer request", I questioned the shop manager about this and he said it was only taken to 15 degrees. I then had the timing checked at another shop who checked it with timing light attached to the #1 injector line, they never pulled the injection lines, they said it was at 15 degrees. The truck does have a lope when dropped into gear when cold, no lope once warmed up just a little. Could valve lash being out cause this? You were pushing like 2 psi at 500 degrees, I don't build practically any boost until 600 degrees. I can also be running along at 55 at 600 degrees with 4 PSI, hit a small hill, go up to 700 degrees and not have boost change at all. What do I need to take loose to see the exhaust turbine to inspect it? Sorry about dragging this on, but I really appreciate the insight.

The timing thing is really the only thing that seems to be the culprit. My turbo shaft is actually brand new so it spins a little better than usual. Over time they get a little oil coking on them and it might not look like much but when you talk about something spinning 100,000RPM it starts to really have an effect. Not too much but down low it seems to spool better. Set your valves a little tighter, such as 0.017 exhaust 0.008 intake. The thing about timing making it have issues is what really interests me. Is the EGT issue the only symptom that happened after the timing was changed? The fuel plate limits fuel, I have NO plate/starwheel/anything and I run cooler than you.. That stuff is more of a "governor" for fuel. They actually have NO function on the truck itself if you drive it sanely. The AFC is there only when you have less than 5psi of boost, it limits the fuel so you don't smoke up the road. After 5psi it assumes you have enough air to burn all of the fuel, so it gets pushed back, past the fuel plate, to which point the fuel plate becomes the limiter. It again is only used if you are really getting on it, but it is more there to control power so you don't burn up a stock clutch or ruin the stock automatic trans. In other words, it has no effect on everyday driving EGT's, it just stops the fueling to prevent too much power. Tell me more about the symptoms that changing the timing had.. Its really the most viable culprit at this point. I have had the timing way out of range and it had similar effects.

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The issues I had after the timing change were not huge, but noticable. White smoke at idle. Greyish smoke when getting on it.Harder starting cold, even like 50 degrees, truck would try to die just after starting. (This has improved somewhat with new injectors.)Lack of low end power, and I had not started tinkering with starwheel before timing change, so power difference might be even bigger if I had. (Has improved somewhat with new injectors.)Engine is alot louder, does not have the smooth 12 valve sound. Has a valve rattle sort of sound.Exhaust (unburnt fuel) smell in the cab when parked idling, or at a red light. If I put my nose right to the exhaust at idle it kind of burns my nose and eyes with the unburnt fuel, I don't know if that is normal- wasn't with my 24 valve.I did seem to get more top end boost after the timing change, but looking back at it, the negatives have not been worth it. The only reason I did it was, with the 24 valve, the "timing box" that I had on it made a huge difference in power, but I now know it is like comparing apples to oranges. I did not gain any real power that I could tell, and did not improve fuel mileage noticeably.I just checked the brakes, no drag what so ever.

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The issues I had after the timing change were not huge, but noticable. White smoke at idle. Greyish smoke when getting on it. Harder starting cold, even like 50 degrees, truck would try to die just after starting. (This has improved somewhat with new injectors.) Lack of low end power, and I had not started tinkering with starwheel before timing change, so power difference might be even bigger if I had. (Has improved somewhat with new injectors.) Engine is alot louder, does not have the smooth 12 valve sound. Has a valve rattle sort of sound. Exhaust (unburnt fuel) smell in the cab when parked idling, or at a red light. If I put my nose right to the exhaust at idle it kind of burns my nose and eyes with the unburnt fuel, I don't know if that is normal- wasn't with my 24 valve. I did seem to get more top end boost after the timing change, but looking back at it, the negatives have not been worth it. The only reason I did it was, with the 24 valve, the "timing box" that I had on it made a huge difference in power, but I now know it is like comparing apples to oranges. I did not gain any real power that I could tell, and did not improve fuel mileage noticeably. I just checked the brakes, no drag what so ever.

This whole time you have been saying it runs perfect and barely smoked but the usual bit when you floor it... That thing is way advanced on timing, just like I suspected. When the timing is advanced really far, it is set up to be efficient at high RPM, and in your case it sounds to be over 20* advanced. The low power will suck, it will smoke, it will have no boost, it will knock like a 24V... It has no efficiency down in the lower RPM. At cranking RPM you might as well forget about it starting because the engine is cold and it is injecting way before the piston hits TDC so there isn't near enough heat built up yet. Ideally the engine should be around 0* while starting, maybe 8* idling, and around 14* at 2000RPM, maybe 20* at 3000RPM. You advance it because the engine moves so fast that you are trying to beat the fuel delivery delay so that it detonates right around TDC, hence the reason you have to keep advancing it for higher RPM. Sled puller trucks running over 4000RPM are running into the high 20's* with timing. The injectors being bigger spray a little bit bigger droplets which take longer to absorb heat and combust, retarding timing (helping out your overly advanced situation). Did the timing light guys mark TDC on the damper or put timing mark tape on it or did you not get to see it? I'm just wondering if they just "told" you it was at 15* to get your money, cause that thing is way too advanced. A true 15* setting would make the truck start fine and it would really be just a tiny bit different than stock. Here is mine when it was over 20* on a 56F morning start..

http-~~-//www.youtube.com/watch?v=DLfiWV2Tg7g

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Well in my defense, it does run O.K., but I guess it takes quite a bit to make a cummins run badly.The damper was marked before the timing light guys checked it, so they just used that.Why would advanced timing cause high EGT's? Is is just because it can not build the correct amount of boost. I am going to have timing reset to stock which is, I believe 14 degrees if I am reading it right on the badge. I won't be able to do it until next week, will let you know.I thought you were running 14.5 degrees of timing, and I now see 13.5. Is that right?Thanks

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Well in my defense, it does run O.K., but I guess it takes quite a bit to make a cummins run badly. The damper was marked before the timing light guys checked it, so they just used that. Why would advanced timing cause high EGT's? Is is just because it can not build the correct amount of boost. I am going to have timing reset to stock which is, I believe 14 degrees if I am reading it right on the badge. I won't be able to do it until next week, will let you know. I thought you were running 14.5 degrees of timing, and I now see 13.5. Is that right? Thanks

I wasn't really trying to chew you out..just saying those subtle things are the things were the things we needed to know.. Any cummins not running top notch is a cummins with a problem.. so any little thing is a clue. Though having had my timing way advanced I do know what you mean by it runs OK. As for the timing deal, you had high EGT's mainly during low RPM. What really advanced timing does is shoot in the fuel really early, way before the piston has reached TDC. Well at low RPM, there is a relatively long amount of time between the injection and TDC. This means the fuel ignites before TDC and is actually trying to turn the engine backwards since it is blowing up while the piston is still trying to come up (compression stroke). This effect is actually part of why advanced timing causes the louder knock. But at low RPM, this is horribly inefficient and causes high EGT's because you need more fuel to drive the truck and overcome the wasted power. When the truck is cold, it doesn't start because it is shooting the fuel in so early that the piston hasn't gone up enough to create enough heat from compression, so it doesn't ignite. My timing is at 13.5 yes. I think. Either that or 14.5 I can't remember. I hate losing low end power and startability. You being in texas I would set it more at the 14.5 mark. On a side note, overly retarded will have a similar reversed effect. It will start up so fast that you won't believe it. Have low end power like you won't believe. And be the doggiest thing in the world over 2000RPM to the point that the only thing that changes when you floor it is the EGT gauge.
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