steeler Posted August 27, 2016 Share Posted August 27, 2016 I've seen this happen more than a couple times. The pump has usually been the culprit over fueling. 1 Quote Link to comment https://www.bigmacktrucks.com/topic/46542-e6-250-piston-failure/page/2/#findComment-343718 Share on other sites More sharing options...
theakerstwo Posted August 27, 2016 Share Posted August 27, 2016 It would not take much more over fuel to do this on a alummin high compression piston like that engine has.I remenber seeing the photos he posted before and it was burning on top maybefrom a crack so thats from over fuel or timing.If this is what it is i would say that it should have been easy to find before it went down by cut the fuel off each cylinder to cut the fuel knock back. 1 Quote glenn akers Link to comment https://www.bigmacktrucks.com/topic/46542-e6-250-piston-failure/page/2/#findComment-343722 Share on other sites More sharing options...
kscarbel2 Posted August 27, 2016 Share Posted August 27, 2016 Any time one "turns up the fuel", they're simultaneously asking for trouble. If I had a dime for every time I've heard a version of this story....... 2 Quote Link to comment https://www.bigmacktrucks.com/topic/46542-e6-250-piston-failure/page/2/#findComment-343727 Share on other sites More sharing options...
Mcrafty1 Posted August 27, 2016 Author Share Posted August 27, 2016 I agree but the question is...why? Deck is perfect and all liners are fine. Quote Link to comment https://www.bigmacktrucks.com/topic/46542-e6-250-piston-failure/page/2/#findComment-343731 Share on other sites More sharing options...
Mcrafty1 Posted August 28, 2016 Author Share Posted August 28, 2016 Well, shes back together and running sweet....on less fuel, and with the new turbo its making 19lbs boost so more air and less fuel may mean less of a chance of a reoccurring piston issue. Im hoping this is the last time im into this engine in my working life.......time will tell. Thanks to all for the pointers on possable reason but i found no smoking guns this time. Quote Link to comment https://www.bigmacktrucks.com/topic/46542-e6-250-piston-failure/page/2/#findComment-343784 Share on other sites More sharing options...
theakerstwo Posted August 28, 2016 Share Posted August 28, 2016 16 hours ago, kscarbel2 said: Any time one "turns up the fuel", they're simultaneously asking for trouble. If I had a dime for every time I've heard a version of this story....... I have set the fuel up on many engines in my younger days but most of them knew how to take care of it. But my question is all who wants more power always say I will only use it sparely but I say why in the first place because when you get tired and sleepy your going to mash on it till you get home. I do. 1 Quote glenn akers Link to comment https://www.bigmacktrucks.com/topic/46542-e6-250-piston-failure/page/2/#findComment-343785 Share on other sites More sharing options...
kscarbel2 Posted August 28, 2016 Share Posted August 28, 2016 19 minutes ago, theakerstwo said: I have set the fuel up on many engines in my younger days but most of them knew how to take care of it. But my question is all who wants more power always say I will only use it sparely but I say why in the first place because when you get tired and sleepy your going to mash on it till you get home. I do. In the old days, if they wanted to block off the puff limiter altogether, or install a 691GC218CP6 puff limiter (the version with the least affect....there's a Service Bulletin), I had no problem with that. But I never encountered a good customer experience from turning up the fuel. Quote Link to comment https://www.bigmacktrucks.com/topic/46542-e6-250-piston-failure/page/2/#findComment-343787 Share on other sites More sharing options...
1965 Posted August 28, 2016 Share Posted August 28, 2016 Always thought you wanted a slight haze out of stack; not all the black smoke Quote Link to comment https://www.bigmacktrucks.com/topic/46542-e6-250-piston-failure/page/2/#findComment-343793 Share on other sites More sharing options...
Timmyb Posted August 28, 2016 Share Posted August 28, 2016 I'm NOT a mechanic. But could you have swapped that injector with say, no 6 injector? Then if problem still occurs then may not be injector. And if no 6 piston melts like previous no 5 it could be injector issue? Just thinking outside of the box. 1 Quote Link to comment https://www.bigmacktrucks.com/topic/46542-e6-250-piston-failure/page/2/#findComment-343802 Share on other sites More sharing options...
gearhead204 Posted August 28, 2016 Share Posted August 28, 2016 a couple of thoughts here is there any thing different in the intake runner of the #5 cyl.? also I have never been around a 250hp e-6 but 19 lbs. of boost sounds low to me, I know a e6 350 will do 28 -32 ish, so do you have a cooler issue? also did any one pre oil this engine before installing the pan to verify that #5 cooling nozzle is performing correctly? also did you check the rocker arm travel on #5 verses the other cyl's? i'm thinking bad cam lobe on the intake could cause it to run hot of not getting enough air. Quote Link to comment https://www.bigmacktrucks.com/topic/46542-e6-250-piston-failure/page/2/#findComment-343880 Share on other sites More sharing options...
Dirtymilkman Posted August 29, 2016 Share Posted August 29, 2016 E6 350 specs are 24ish psi 1 Quote Link to comment https://www.bigmacktrucks.com/topic/46542-e6-250-piston-failure/page/2/#findComment-343883 Share on other sites More sharing options...
Mcrafty1 Posted August 29, 2016 Author Share Posted August 29, 2016 9 hours ago, gearhead204 said: a couple of thoughts here is there any thing different in the intake runner of the #5 cyl.? also I have never been around a 250hp e-6 but 19 lbs. of boost sounds low to me, I know a e6 350 will do 28 -32 ish, so do you have a cooler issue? also did any one pre oil this engine before installing the pan to verify that #5 cooling nozzle is performing correctly? also did you check the rocker arm travel on #5 verses the other cyl's? i'm thinking bad cam lobe on the intake could cause it to run hot of not getting enough air. No, nothing different with the intake....141/2 to 17 is the norm for boost, the cooling nozzle was checked and aimed to spec, rocker arm travel was checked and a visual of the cam lobes confirm its condition to be like the others. 1 Quote Link to comment https://www.bigmacktrucks.com/topic/46542-e6-250-piston-failure/page/2/#findComment-343907 Share on other sites More sharing options...
fjh Posted August 29, 2016 Share Posted August 29, 2016 (edited) 14 hours ago, gearhead204 said: a couple of thoughts here is there any thing different in the intake runner of the #5 cyl.? also I have never been around a 250hp e-6 but 19 lbs. of boost sounds low to me, I know a e6 350 will do 28 -32 ish, so do you have a cooler issue? also did any one pre oil this engine before installing the pan to verify that #5 cooling nozzle is performing correctly? also did you check the rocker arm travel on #5 verses the other cyl's? i'm thinking bad cam lobe on the intake could cause it to run hot of not getting enough air. Your 350 is hot not the norm the Boost your getting is what a E7 400 would make! he mentioned the cooler was aimed earlier in the post! Edited August 29, 2016 by fjh Quote Link to comment https://www.bigmacktrucks.com/topic/46542-e6-250-piston-failure/page/2/#findComment-343922 Share on other sites More sharing options...
theakerstwo Posted August 29, 2016 Share Posted August 29, 2016 Another ideal about the piston cooler,It may have been aimed at some time but that would be with the piston out.It would be easy if the cooler is still in the block to get bent bythe rod when installing the piston. Quote glenn akers Link to comment https://www.bigmacktrucks.com/topic/46542-e6-250-piston-failure/page/2/#findComment-343953 Share on other sites More sharing options...
Mcrafty1 Posted August 29, 2016 Author Share Posted August 29, 2016 2 hours ago, theakerstwo said: Another ideal about the piston cooler,It may have been aimed at some time but that would be with the piston out.It would be easy if the cooler is still in the block to get bent bythe rod when installing the piston. The cooler is aimed right, I have been on my back guiding the connecting rod down by the nozzle the last two times so I'm sure it is still right. I do believe the fuel pressure was to much and I also believe that number five must be the 'hot hole' in these engines. Time will tell, I cut the fuel back enough so I haven't seen the pyrometer go above 875 degrees....before I turned it back I could run it up into the 1000s without much effort. Quote Link to comment https://www.bigmacktrucks.com/topic/46542-e6-250-piston-failure/page/2/#findComment-343958 Share on other sites More sharing options...
Dirtymilkman Posted August 30, 2016 Share Posted August 30, 2016 Has this motor always had the same head on it over #5? Maybe the injector hole is drilled at a wrong angle? Just brainstorming..... Quote Link to comment https://www.bigmacktrucks.com/topic/46542-e6-250-piston-failure/page/2/#findComment-343993 Share on other sites More sharing options...
gearhead204 Posted August 30, 2016 Share Posted August 30, 2016 I understood that the cooler nozzle was aimed , my question is ..... has its proper operation been verified! as for the boost on the 350's that would explain why the 4 or 5 I ever ran I liked so well..... could always make a 400 cummins look sick! Quote Link to comment https://www.bigmacktrucks.com/topic/46542-e6-250-piston-failure/page/2/#findComment-344005 Share on other sites More sharing options...
Mcrafty1 Posted August 30, 2016 Author Share Posted August 30, 2016 7 hours ago, Dirtymilkman said: Has this motor always had the same head on it over #5? Maybe the injector hole is drilled at a wrong angle? Just brainstorming..... No, the head was changed two pistons ago. Quote Link to comment https://www.bigmacktrucks.com/topic/46542-e6-250-piston-failure/page/2/#findComment-344015 Share on other sites More sharing options...
Mcrafty1 Posted August 30, 2016 Author Share Posted August 30, 2016 5 hours ago, gearhead204 said: I understood that the cooler nozzle was aimed , my question is ..... has its proper operation been verified! as for the boost on the 350's that would explain why the 4 or 5 I ever ran I liked so well..... could always make a 400 cummins look sick! I can't say for sure that it was......but would it go for two years between pistons if it were not working? I talked with a man yesterday that has a 400 and has the same experience with his......since he cranked it up, #5 every time, I'm hoping between my old turbo not up to par and cutting the fuel back that I am going to be running this motor longer than the last two. 1 Quote Link to comment https://www.bigmacktrucks.com/topic/46542-e6-250-piston-failure/page/2/#findComment-344016 Share on other sites More sharing options...
1965 Posted August 30, 2016 Share Posted August 30, 2016 If was the nozzle; wouldn't it be more likely to gauld around pin area instead of burning from top down Quote Link to comment https://www.bigmacktrucks.com/topic/46542-e6-250-piston-failure/page/2/#findComment-344017 Share on other sites More sharing options...
theakerstwo Posted August 30, 2016 Share Posted August 30, 2016 19 minutes ago, 1965 said: If was the nozzle; wouldn't it be more likely to gauld around pin area instead of burning from top down Yes your right. Quote glenn akers Link to comment https://www.bigmacktrucks.com/topic/46542-e6-250-piston-failure/page/2/#findComment-344018 Share on other sites More sharing options...
gearhead204 Posted September 1, 2016 Share Posted September 1, 2016 maybe one of the engineers will chime in here, but I always understood that the oil spray was to aid in heat removal from the underside of the piston , the ill performing turbo I would suspect would be another major factor especially in a fueled up engine, if over fueled during long pulls. as for why #5 every time if this is the case? that's what brings me back to the cooling nozzle. I would think if the block had a bad internal casting on the web around #5 liner that retarded coolant flow we would see piston skirt and liner damage similar to cold seizing in a two stroke. Quote Link to comment https://www.bigmacktrucks.com/topic/46542-e6-250-piston-failure/page/2/#findComment-344211 Share on other sites More sharing options...
Dirtymilkman Posted September 1, 2016 Share Posted September 1, 2016 2 hours ago, gearhead204 said: maybe one of the engineers will chime in here, but I always understood that the oil spray was to aid in heat removal from the underside of the piston , the ill performing turbo I would suspect would be another major factor especially in a fueled up engine, if over fueled during long pulls. as for why #5 every time if this is the case? that's what brings me back to the cooling nozzle. I would think if the block had a bad internal casting on the web around #5 liner that retarded coolant flow we would see piston skirt and liner damage similar to cold seizing in a two stroke. That darn retarded coolant........... 1 Quote Link to comment https://www.bigmacktrucks.com/topic/46542-e6-250-piston-failure/page/2/#findComment-344219 Share on other sites More sharing options...
Mcrafty1 Posted September 17, 2016 Author Share Posted September 17, 2016 On 08/28/2016 at 3:08 AM, Timmyb said: I'm NOT a mechanic. But could you have swapped that injector with say, no 6 injector? Then if problem still occurs then may not be injector. And if no 6 piston melts like previous no 5 it could be injector issue? Just thinking outside of the box. Thanks, the injector was swapped around and even relaced the last time Quote Link to comment https://www.bigmacktrucks.com/topic/46542-e6-250-piston-failure/page/2/#findComment-345981 Share on other sites More sharing options...
Popular Post Mcrafty1 Posted September 17, 2016 Author Popular Post Share Posted September 17, 2016 Update.... The new motor is working well, the combination of less fuel and more boost seems to be doing it good. The new turbo is pushing 20lbs of boost and the egts are never above 850...I believe this is going to be a good build.. ......and the trucks pulls as good as before to boot. 3 Quote Link to comment https://www.bigmacktrucks.com/topic/46542-e6-250-piston-failure/page/2/#findComment-345982 Share on other sites More sharing options...
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