pmolitor Posted August 8, 2013 Share Posted August 8, 2013 my 79 RS with an endt676 seems to be blowing more black smoke than it used to. Doesn't seem to have the power it used to. Doesn't use any oil and not much blow by. just a lot of smoke under hard pulls. I replaced all the injectors last fall. could the pump need overhauled or is there something else I should look for? Quote Link to comment https://www.bigmacktrucks.com/topic/32256-overfueling/ Share on other sites More sharing options...
2stacksuperdog Posted August 8, 2013 Share Posted August 8, 2013 Check the air filter? 1 Quote Matt Link to comment https://www.bigmacktrucks.com/topic/32256-overfueling/#findComment-198627 Share on other sites More sharing options...
Mack Doctor Jr. Posted August 8, 2013 Share Posted August 8, 2013 my first thought there 2 stack! Quote Link to comment https://www.bigmacktrucks.com/topic/32256-overfueling/#findComment-198632 Share on other sites More sharing options...
pmolitor Posted August 8, 2013 Author Share Posted August 8, 2013 It's new...first thing I thought of also. changed it last week. Quote Link to comment https://www.bigmacktrucks.com/topic/32256-overfueling/#findComment-198638 Share on other sites More sharing options...
j hancock Posted August 8, 2013 Share Posted August 8, 2013 Random thought.If the air relay on the intake manifold for the puff limiter is screwed up it could be sending a false signal to the injector pump. It could explain the black smoke. Quote JimIt doesn't cost anything to pay attention. Link to comment https://www.bigmacktrucks.com/topic/32256-overfueling/#findComment-198643 Share on other sites More sharing options...
rsb502 Posted August 8, 2013 Share Posted August 8, 2013 Random thought.If the air relay on the intake manifold for the puff limiter is screwed up it could be sending a false signal to the injector pump. It could explain the black smoke.in a pull under throttle the puff limiter is all the way off, if it was messed up it wouldnt run well but there wouldnt be any excess fuel smoke either. If the air filter was stopped up and the fuel filters were good it would get extra smoke, if the fuel filters were clogged it would smoke less, if the smoke limiter wasnt moving from the idle position it would smoke less, if the lift pump were going out it would smoke less, if the injection pump was taking a dump it may smoke more, it would definitely run worse, just out of curiosity you havent gotten it real hot have you? If you inadvertantly got the cylinder temp too high on a long pull with a load as I remember you saying you had isues with in the past the tips on the nozzles may be melted and just drizzling fuel instead of atomizing it, thus making it smoke more and run worse, actually thats the first place Id check after the obvious external stuff on a Mechanical engine. Quote "Any Society that would give up a little LIBERTY to gain a little SECURITY will Deserve Neither and LOSE BOTH" -Benjamin Franklin"If your gonna be STUPID, you gotta be TOUGH" "You cant always get what you want, but if you try sometimes you get what you need" Link to comment https://www.bigmacktrucks.com/topic/32256-overfueling/#findComment-198649 Share on other sites More sharing options...
turckster Posted August 8, 2013 Share Posted August 8, 2013 Basically, if the puff limiter is not working properly you will either have no smoke and low power or allot of smoke and slightly more power in the low rpm's. Since you have excessive smoke and feel like it has less power, I would take a good look at both inlet and outlet side of the turbo. Make sure there are no excessive leaks on the pressure side after the turbo. 1 Quote Link to comment https://www.bigmacktrucks.com/topic/32256-overfueling/#findComment-198656 Share on other sites More sharing options...
pmolitor Posted August 8, 2013 Author Share Posted August 8, 2013 I don't think this one has been hot.... my memory isn't all that good anymore:-). I lost my pyro early this summer. new one will be in in the morning. I did figure out the 90 ch with the em6l problem. the fuel filter housings were full of what looked like rags.... cut all my power! cleaned them out on the side of the road one day sfter it died on me. I think that was the one that you remember 84duperdog. Quote Link to comment https://www.bigmacktrucks.com/topic/32256-overfueling/#findComment-198658 Share on other sites More sharing options...
pmolitor Posted August 8, 2013 Author Share Posted August 8, 2013 no turbo leaks.. how do.I tell if pump is getting weak? or out of time? Quote Link to comment https://www.bigmacktrucks.com/topic/32256-overfueling/#findComment-198660 Share on other sites More sharing options...
39 Baby Mack Posted August 8, 2013 Share Posted August 8, 2013 Basically, if the puff limiter is not working properly you will either have no smoke and low power or allot of smoke and slightly more power in the low rpm's. Since you have excessive smoke and feel like it has less power, I would take a good look at both inlet and outlet side of the turbo. Make sure there are no excessive leaks on the pressure side after the turbo. How about the gaskets on the intercooler core, the clamps on or the small hose going to the tip turbine fan, the clamps or the hose between the intercooler manifoldand rear intake manifold?Ron Quote Link to comment https://www.bigmacktrucks.com/topic/32256-overfueling/#findComment-198694 Share on other sites More sharing options...
theakerstwo Posted August 8, 2013 Share Posted August 8, 2013 Also check and see if the termocoupler for the pyrometer is in the manifold. If so and your pyrometer has went bad it could have drop the thermocoupler inside taking the turbo wheel out with it.I have seen it a few times years ago when they installed in manifold. I want them in the exhaust behind the turbo. Quote glenn akers Link to comment https://www.bigmacktrucks.com/topic/32256-overfueling/#findComment-198757 Share on other sites More sharing options...
Superdog Posted August 8, 2013 Share Posted August 8, 2013 have you cleaned the intercooler core lately?? Quote Link to comment https://www.bigmacktrucks.com/topic/32256-overfueling/#findComment-198766 Share on other sites More sharing options...
pmolitor Posted August 9, 2013 Author Share Posted August 9, 2013 superdog, yes. I just got home from tearing all the air ducks off the truck. I think the turbo might be bad. no side to side play, but the shaft moves back and forth a lot. I'm headed to mack first thing in the morning. Quote Link to comment https://www.bigmacktrucks.com/topic/32256-overfueling/#findComment-198821 Share on other sites More sharing options...
pmolitor Posted August 9, 2013 Author Share Posted August 9, 2013 theakerstwo, replaced the pyro first thing this morning. thermo coupler was intact. Quote Link to comment https://www.bigmacktrucks.com/topic/32256-overfueling/#findComment-198825 Share on other sites More sharing options...
rsb502 Posted August 9, 2013 Share Posted August 9, 2013 Go to a Borg Warner turbo dealer for a turbo it'll be half price and its a better turbo, I can cross reference your p/n to a Borg number if you have it off your turbo. Quote "Any Society that would give up a little LIBERTY to gain a little SECURITY will Deserve Neither and LOSE BOTH" -Benjamin Franklin"If your gonna be STUPID, you gotta be TOUGH" "You cant always get what you want, but if you try sometimes you get what you need" Link to comment https://www.bigmacktrucks.com/topic/32256-overfueling/#findComment-198839 Share on other sites More sharing options...
pmolitor Posted August 9, 2013 Author Share Posted August 9, 2013 see if this post. Quote Link to comment https://www.bigmacktrucks.com/topic/32256-overfueling/#findComment-198844 Share on other sites More sharing options...
pmolitor Posted August 9, 2013 Author Share Posted August 9, 2013 upsidedown of course. Quote Link to comment https://www.bigmacktrucks.com/topic/32256-overfueling/#findComment-198845 Share on other sites More sharing options...
pmolitor Posted August 14, 2013 Author Share Posted August 14, 2013 new turbo = no change.. old one was getting bad. played with aneroid valve. got the vavle working again which is cool to see that ut actually works, but it leaks air. still no power and extremely high egts. Quote Link to comment https://www.bigmacktrucks.com/topic/32256-overfueling/#findComment-199723 Share on other sites More sharing options...
rsb502 Posted August 14, 2013 Share Posted August 14, 2013 How much boost are you making with the new turbo? Did you idle the truck up to about 1000rpm and spray soapy water all over all the charge air pipes and intercooler to make sure it wasn't leaking? How high are the egt's? Quote "Any Society that would give up a little LIBERTY to gain a little SECURITY will Deserve Neither and LOSE BOTH" -Benjamin Franklin"If your gonna be STUPID, you gotta be TOUGH" "You cant always get what you want, but if you try sometimes you get what you need" Link to comment https://www.bigmacktrucks.com/topic/32256-overfueling/#findComment-199832 Share on other sites More sharing options...
pmolitor Posted August 15, 2013 Author Share Posted August 15, 2013 do have a boost gauge yet. will be in in morning. rechecked all fittings when I installed turbo. will do again in morning with soapy water. egts are getting up to 1200deg fast. and staying up even when not under a load. Quote Link to comment https://www.bigmacktrucks.com/topic/32256-overfueling/#findComment-199889 Share on other sites More sharing options...
pmolitor Posted August 15, 2013 Author Share Posted August 15, 2013 motor is an EM6-300R. Not a endt 676. don't know why I thought it was the other. major brain fart. Quote Link to comment https://www.bigmacktrucks.com/topic/32256-overfueling/#findComment-199890 Share on other sites More sharing options...
rsb502 Posted August 15, 2013 Share Posted August 15, 2013 With egt that's high you have too much fuel and not enough air or some slobbering injector nozzles that aren't atomizing your fuel. One things for sure you'll burn that sucker down if you drive it like that long, I try to keep my egt around 900-1000 on long pulls loaded heavy normal driving light they shouldn't top 700-800 depending on.how hot your pump/injectors are. Check to make sure your not losing your charge air and if not, remove the cold (intake manifold) side charge air pipe and see what kind of flow your getting thru the cooler, it would be odd but possible for a blockage or internal damage to restrict the charge air flow thru the cooler. Quote "Any Society that would give up a little LIBERTY to gain a little SECURITY will Deserve Neither and LOSE BOTH" -Benjamin Franklin"If your gonna be STUPID, you gotta be TOUGH" "You cant always get what you want, but if you try sometimes you get what you need" Link to comment https://www.bigmacktrucks.com/topic/32256-overfueling/#findComment-199897 Share on other sites More sharing options...
pmolitor Posted August 15, 2013 Author Share Posted August 15, 2013 thanks for all the info. I'll let you know what I find in the morning. Quote Link to comment https://www.bigmacktrucks.com/topic/32256-overfueling/#findComment-199900 Share on other sites More sharing options...
pmolitor Posted August 15, 2013 Author Share Posted August 15, 2013 update. can't find boost gauge, ordered new on online. Followed my driver today. have some white smoke with the dark smoke. going to run oil samples tomorrow and pressure test the cooling system. kind of looking like a headgasket or cracked sleeve. I'm out of ideas. Quote Link to comment https://www.bigmacktrucks.com/topic/32256-overfueling/#findComment-199974 Share on other sites More sharing options...
rsb502 Posted August 16, 2013 Share Posted August 16, 2013 Your still running it with 1200 degree egt's? well did you check the whole charge air system for leaks, you should see bubbles if you spray it down, have you thought about pulling your injector nozzles? Im still thinking if you dont have any charge air leaks its getting too hot and has too much fuel smoke, that combined with low power makes me want to pull the nozzles and look for one or more to be melted. Quote "Any Society that would give up a little LIBERTY to gain a little SECURITY will Deserve Neither and LOSE BOTH" -Benjamin Franklin"If your gonna be STUPID, you gotta be TOUGH" "You cant always get what you want, but if you try sometimes you get what you need" Link to comment https://www.bigmacktrucks.com/topic/32256-overfueling/#findComment-199986 Share on other sites More sharing options...
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