Junior9009 Posted April 4, 2015 Share Posted April 4, 2015 Is there a way to bypass the puff limitier on an E-6 350? Quote Link to comment Share on other sites More sharing options...
blackdog2 Posted April 4, 2015 Share Posted April 4, 2015 The line going from your anaroy valve from your brake valve on dash install a air toggle switch so if you get pulled over you could flip it quick mount it in the ash tray..They are getting a little smarter Quote Ed Link to comment Share on other sites More sharing options...
1MACK1 Posted April 4, 2015 Share Posted April 4, 2015 Well worth doing great to flick over when pulling up thru winding hills Quote Link to comment Share on other sites More sharing options...
r686st Posted April 4, 2015 Share Posted April 4, 2015 Could you post some pictures of the parts? I'm looking to do this on my E7-350 and EM7-300. Is it just for show or does it help with power as well? 1 Quote Link to comment Share on other sites More sharing options...
blackdog2 Posted April 4, 2015 Share Posted April 4, 2015 15 to 20 + hp night and day difference typical air toggle switch 1/8 ports. 1 Quote Ed Link to comment Share on other sites More sharing options...
b61fred Posted April 4, 2015 Share Posted April 4, 2015 So what makes these aneroid valves work? I would guess that the manifold pressure has to meet "x" psi before the rack on the pump would have full travel. I also guess that it gets it's air supply from the parking brake so it will have full rack travel while parked. I don't know why that would be a good thing but I need schooled about this. I want to keep the aneroid on my b model because I would like for it to not smoke like crazy but having a valve for those moments when you want more power would be neat. Quote 15 gears...no waiting! Link to comment Share on other sites More sharing options...
Green Dash Posted April 4, 2015 Share Posted April 4, 2015 The mechanic where I used to work mounted an additional air brake knob assembly on the far right panel of the dashboard and covered the words "Parking Brake" with a piece of paper that said "Puff Limiter, in-on out-off". It was after I stopped driving that truck that I realized that was a bad idea and at least he should've known better. 1 Quote Jim Link to comment Share on other sites More sharing options...
Popular Post theakerstwo Posted April 4, 2015 Popular Post Share Posted April 4, 2015 B61 fred the puff limiter does not give the pump any more rack with out air to it than if it was not conncted.But with it disconnected it will give the pump full rack even when the boost is not up.Meaning it will have more response and smoke but when the boost builds it will not have anymore HP than the pump is set for.But you can get in to tenth gear quicker but will not pull a hill any faster.I work with several macks ever day and mine is the only one that does not smoke but the guys that have them smoking think they are running better.The puff liniter is only holding your foot off of the gas pedal until your boost starts to build and then the pufflimiter lets you smash it some more.If some one gained HP by taking the air off of the puff limiter there was a problem with the system not adjusted right or air problem.To me most guys can find more things to worry about than making some smoke and getting in a gear quicker. 3 Quote glenn akers Link to comment Share on other sites More sharing options...
Swishy Posted April 4, 2015 Share Posted April 4, 2015 we took the doodadd outa the pump n packed it out with a washer to get better response from the beastcya§wishy 1 Quote Link to comment Share on other sites More sharing options...
Timmyb Posted April 5, 2015 Share Posted April 5, 2015 with regard to the e7, someone here might clarify but I am under the assumption they have a different fuel pump and don't have a puff limiter. My e6 has puff limiter disconnected and is putting fuel in the oil. Quote Link to comment Share on other sites More sharing options...
bobcotkg Posted April 5, 2015 Share Posted April 5, 2015 The E7 has a aneroid valve (puff limiter) and if you unhook it it will run worse!!! My E6 had the same setup on it. The valve that the line from the intake goes to is obviously the aneroid valve. Its on the governor. There is a plug that takes an allen wrench to take it out. Get in there with a flat tip screw driver, and turn it so it goes away from the radiator. (If I remember right) The goal is to have less spring tension on it. Its pretty obvious, nothing to screw up. Take it for a little spin. If you went the wrong way It'll be a turd...Just turn it back the other way.This setup is different than the earlier pumps. You could simply unhook them, or put a valve in the line... Quote Link to comment Share on other sites More sharing options...
Lmackattack Posted April 5, 2015 Share Posted April 5, 2015 I have mine on a air switch in the dash.It does not give more overall power but it does help keep the boost up between shifts as it dumps full fuel sooner. It will smoke more between shifts and can put fuel in the oil.you should notice the truck is a little faster off the line but thats not because of more overall HP its that the HP comes on quicker at a lower RPM Quote Link to comment Share on other sites More sharing options...
theakerstwo Posted April 5, 2015 Share Posted April 5, 2015 The E7 has a LDA valve which some call it a aeroid valve.It has to have a line connected to it to the intake manifold to see boost or it will never fuel 100 %. 1 Quote glenn akers Link to comment Share on other sites More sharing options...
Popular Post gearhead204 Posted April 5, 2015 Popular Post Share Posted April 5, 2015 the puff limiter is best used on a e-9 with single exhaust and a short stack, then when passing slower trucks you flip the dash switch and grab a taller gear and fill the cab of whatever truck your passing with the scent of a dogs ass! 3 Quote Link to comment Share on other sites More sharing options...
b61fred Posted April 5, 2015 Share Posted April 5, 2015 So.... After reading the book( Thanks Swishy) I see why it is hooked to the air brake valve. The injection rack requires full fuel to start the engine, after starting, the governor will pull the rack backwards. You would never start the engine without the air brakes set.... Unless you have a B model with a mechanical parking brake. This wouldn't be a problem since my truck looses all it's air pressure when it sits overnight, but going to fix that soon. I will have to run an air valve just so it will start, and a added bonus boost switch. Quote 15 gears...no waiting! Link to comment Share on other sites More sharing options...
MACKS Posted April 5, 2015 Share Posted April 5, 2015 The E7 has a LDA valve which some call it a aeroid valve.It has to have a line connected to it to the intake manifold to see boost or it will never fuel 100 %.I never messed with mine on my 96 cl,e-7 but sometimes I wonder if it even works,can't tell any difference as far as smoke coming out of the stack doing a snap test with or without the brake applied,should i see a difference,one think for sure my oil stays clean between changes,there is no soot at all in the engine or the oil,But I have a feeling it should be getting more fuel. 1 Quote Link to comment Share on other sites More sharing options...
theakerstwo Posted April 5, 2015 Share Posted April 5, 2015 Macks the LDA valve has nothen to do with the park brakes.We are into two different system now. Quote glenn akers Link to comment Share on other sites More sharing options...
MACKS Posted April 5, 2015 Share Posted April 5, 2015 Macks the LDA valve has nothen to do with the park brakes.We are into two different system now.Ok thanks. Quote Link to comment Share on other sites More sharing options...
dds92780 Posted April 5, 2015 Share Posted April 5, 2015 On the E7 if you mess with the aneroid spring and weaken it , it will make more black smoke and allowing the turbo to spool sooner but only if you don't push the pedal down all the way. Let's say if you never messed with the aneroid and turned the pump up and expected to be quicker off the line. It won't be because they set it up that way to create zero smoke and giving it a delay which is what i feel. Now if you have the spring weakened and floor it, it will just blow black smoke and almost be slower. You need to find the right balance between it all and most of all just control your foot.I can walk from most macks out there without making any black smoke at all. When you have your puff limiter or aneroid spring messed with, all you have to do is ease into the throttle and then just start to floor it. You can still get plenty of power this way. That is almost the way the truck is setup to begin with, but i feel the aneroid is setup way to stiff from the factory making it very sluggish.When i first got my e7 i was comparing it to my old e6 300 and it didnt have any torque like my old truck. The e6 with that puff limiter removed gives it instant punch. Thats when i started to mess with things on my e7 and i've been happy. Quote Slow and Steady Wins the Race! Link to comment Share on other sites More sharing options...
Trashyside Posted September 2, 2020 Share Posted September 2, 2020 Can someone show me what and where the puff limiter is on the 2001 E7 460 motor Quote Link to comment Share on other sites More sharing options...
Swishy Posted September 2, 2020 Share Posted September 2, 2020 Read up the page where eye scanned a cupla pages from the mack book cya Quote Link to comment Share on other sites More sharing options...
Mark T Posted September 2, 2020 Share Posted September 2, 2020 (edited) If the puff limiter works the way it should. you shouldn't have lots of smoke and it should run as well as the pump is set. Releasing the parking brake should send air to the reversing relay in the intake manifold, then from there the air is metered to the puff limiter's cylinder on the pump.....which can take a few tries to shim correctly. The reason for working from the parking brake is for full rack travel for cold starts, as an engine requires a rich mixture when it's cold ....so no air to it allows full fuel at cranking when you floor it. and on that 460, the puff limiter is called an ECM (loL) Edited September 2, 2020 by Mark T add text Quote Link to comment Share on other sites More sharing options...
turckster Posted September 3, 2020 Share Posted September 3, 2020 The puff limiter is to limit rack travel to limit smoke. As manifold pressure builds the bimba valve(on inj. pump) allows more rack travel. As long as you have the correct reversing relay and the bimba valve is correctly shimmed, the engine should run just fine. The engine will get full rack travel until the park brake valve is pushed in to aid start-up. On an engine with a LDA, the rack is mechanically restricted until manifold pressure overcomes the LDA allowing full rack travel. Quote Link to comment Share on other sites More sharing options...
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