JoeH Posted August 9, 2023 Share Posted August 9, 2023 The rule on adjusting Mack valves is "follow the book to the T" 1 1 Quote Link to comment https://www.bigmacktrucks.com/topic/73048-e7-low-power-help/page/3/#findComment-536648 Share on other sites More sharing options...
Joey Mack Posted August 9, 2023 Share Posted August 9, 2023 Exactly!! I bet I post that 2 dozen times a year. 1 Quote Link to comment https://www.bigmacktrucks.com/topic/73048-e7-low-power-help/page/3/#findComment-536650 Share on other sites More sharing options...
fjh Posted August 9, 2023 Share Posted August 9, 2023 On 7/27/2023 at 12:16 PM, Joey Mack said: I'm impressed that you found a Pro Link 9000.. that's what I cut my teeth on back in 2000... Yup me too ! I spent a lot of quality time with that dam thing! once your on to it and figure which drawers everthing are in its a snap to work with ! its a mighty fine unit! Unfortunately these days you need to be a puter programmer as well! The thing with the prolink is your in your out in minutes Not pissing around having to wait for shit to load so you can use it! And it stayed the same for the most part ! They kept moving stuff around in the Vmac soft ware! it was getting more and more frustrating to use! 1 Quote Link to comment https://www.bigmacktrucks.com/topic/73048-e7-low-power-help/page/3/#findComment-536654 Share on other sites More sharing options...
Joey Mack Posted August 9, 2023 Share Posted August 9, 2023 Can I get an,, AMEN!! Quote Link to comment https://www.bigmacktrucks.com/topic/73048-e7-low-power-help/page/3/#findComment-536655 Share on other sites More sharing options...
fjh Posted August 9, 2023 Share Posted August 9, 2023 8 minutes ago, Joey Mack said: Can I get an,, AMEN!! 🙏 1 Quote Link to comment https://www.bigmacktrucks.com/topic/73048-e7-low-power-help/page/3/#findComment-536658 Share on other sites More sharing options...
fjh Posted August 9, 2023 Share Posted August 9, 2023 14 hours ago, Dtech said: We are back on this project today I have a Question for you E7 Mack experts. We checked the valve lash using the procedure in the book, however we noticed that when the intake valve is fully open on a cylinder the Exhaust valve on the same cylinder has lots of lash! This means that Mack does not adjust lash on the base circle of the camshaft lobe or we are out of time. Has anyone with experience ever noticed this? Just to be clear if I turn the Crankshaft in the direction of rotation to the cylinder marked on the flywheel 1-6, for example, that lash is correct however if I keep rotating it to the next set to be adjusted, the lash becomes larger than 0.024 around in the .060 thousandths on that previously adjusted exhaust valve? It will keep that gap through out the intake stroke and comes back to the .024 right before TDC on the compression stroke. Is this normal? I also noted that this only happens on the Exhaust valve the intake lash remains the same through out all stokes other than the intake stroke of course The mechanic that built this motor told me he had installed a used Crankshaft. He had to change the Crankshaft drive gear due to size deference, the new use crankshaft had a larger gear on it !!! so he swapped it with the original drive gear. I did check crankshaft to camshaft timing using the book procedure it seem to be on the money, I also did notice that Valve overlap is happening on TDC. I also double checked flywheel to crankshaft timing by pulling the nozzle on #1 cylinder and confirmed TDC #1 alines with TC mark on flywheel. Thanks For your help That extra lash is for engine brake ignore this! Is the engine equipped with dyna tard ? all is good! Was the cam replaced? or new cam gear changed? 1 Quote Link to comment https://www.bigmacktrucks.com/topic/73048-e7-low-power-help/page/3/#findComment-536662 Share on other sites More sharing options...
fjh Posted August 9, 2023 Share Posted August 9, 2023 36 minutes ago, fjh said: That extra lash is for engine brake ignore this! Is the engine equipped with dyna tard ? all is good! Was the cam replaced? or new cam gear changed? so I re read the the post the cam was changed I noticed so I believe there was an offset cam key available for these ( Joe correct me if Im wrong) Was the original key used!? Quote Link to comment https://www.bigmacktrucks.com/topic/73048-e7-low-power-help/page/3/#findComment-536668 Share on other sites More sharing options...
Dtech Posted August 9, 2023 Author Share Posted August 9, 2023 Original Cam and Cam gear was used with the original key. This makes sense with the Engine brake, since the compression brake has no Injector rocker arm to be the slave it has to use another cylinders exhaust rocker arm. Yes it is a Dyna Tard. Thanks for clearing this up. Does anyone know if 26 psi at the Injection pump is enough fuel psi? Quote Link to comment https://www.bigmacktrucks.com/topic/73048-e7-low-power-help/page/3/#findComment-536672 Share on other sites More sharing options...
Joey Mack Posted August 9, 2023 Share Posted August 9, 2023 Are you using a barring tool? Are you pulling the ratchet towards the oil pan? Quote Link to comment https://www.bigmacktrucks.com/topic/73048-e7-low-power-help/page/3/#findComment-536674 Share on other sites More sharing options...
Dtech Posted August 9, 2023 Author Share Posted August 9, 2023 Yes I am using the turning tool in the flywheel housing, yes I am turning it the direction of rotation I am not having any trouble setting the lash or checking it. I am going by the book always do. I was just confused my the increase in the lash that is not common in Diesels. I am a 35 year diesel tech not my first rodeo lol. This E7 just has me scratching my head. Does anyone know the answer to my fuel psi ? I need to rule it out Thanks Quote Link to comment https://www.bigmacktrucks.com/topic/73048-e7-low-power-help/page/3/#findComment-536678 Share on other sites More sharing options...
Joey Mack Posted August 9, 2023 Share Posted August 9, 2023 I don't know fuel pressure off the top of my head. What year engine? I have many E-7 shop manuals in my shop at home, and may be able to get you a picture of the page. Quote Link to comment https://www.bigmacktrucks.com/topic/73048-e7-low-power-help/page/3/#findComment-536679 Share on other sites More sharing options...
Dtech Posted August 9, 2023 Author Share Posted August 9, 2023 Great Thanks 1995 E7 in a Ch613. 1 Quote Link to comment https://www.bigmacktrucks.com/topic/73048-e7-low-power-help/page/3/#findComment-536683 Share on other sites More sharing options...
Joey Mack Posted August 9, 2023 Share Posted August 9, 2023 I bet this has most of the answers you are looking for. Jojo Quote Link to comment https://www.bigmacktrucks.com/topic/73048-e7-low-power-help/page/3/#findComment-536693 Share on other sites More sharing options...
Joey Mack Posted August 9, 2023 Share Posted August 9, 2023 (edited) Hat's off to you for lasting 35 years... I burned out at 25 years.. Now I have a cushy city job, with my own truck, list of work to do, and a handheld radio.. and no one baby sit's me... I am currently trying to be a driver trainer for my dept. We need CDL drivers. Edited August 10, 2023 by Joey Mack Pore cell fone sperring Quote Link to comment https://www.bigmacktrucks.com/topic/73048-e7-low-power-help/page/3/#findComment-536696 Share on other sites More sharing options...
fjh Posted August 10, 2023 Share Posted August 10, 2023 22 hours ago, Dtech said: Original Cam and Cam gear was used with the original key. This makes sense with the Engine brake, since the compression brake has no Injector rocker arm to be the slave it has to use another cylinders exhaust rocker arm. Yes it is a Dyna Tard. Thanks for clearing this up. Does anyone know if 26 psi at the Injection pump is enough fuel psi? Taking the whole fac of is a bit of a pain as it has a tamper proof screw still doable however. . I would pull the 4 screws on the Fac and inspect diaphragm my self ! that way you get to see and understand what makes it tick! 😁 Your Good fuel pressure wise ! (Actual personal experience talking here) anything over 20 under load is fine it will pull ! 15 will still pull ok but not great ! 10 not so much think spec is 20 -35 ! If you take the little cap off the end of the fac dodad there youll find a screw with a jam nut ! Loosen the jam nut turn the screw in (count the turns) crank it in two to three turns see if this changes your situation ! it will lay down some coal but this may tell us a little more about whats going on and will take some of the sluggishness out of your take offs! you can play with this a by tweeking the screw in little bit by little bit to get the desired lack of coal by turning it in 1/2 turn at a time! Taking the whole fac of is a bit of a pain as it has a tamper proof screw still doable however. Also the don't use the timing specs on that page as gospel I beleive its a vmac spec your in the zone at 19 to 24 for your App in my opinion !! Edit I see Joe posted the the spec page sorry my bad ! 19 min ! 🙄 Quote Link to comment https://www.bigmacktrucks.com/topic/73048-e7-low-power-help/page/3/#findComment-536718 Share on other sites More sharing options...
Dtech Posted August 11, 2023 Author Share Posted August 11, 2023 Thanks FJH for your advice, However I am a little loss on the FAC I know the older mechanical injection pumps had them. I can not find anything like that on this pump? It only has wires going into the back of it. It has no lines from the intake manifold to the injection pump. It also does not have a Boost psi sensor that I can find only intake air temp that is also the only sensor that is in the manifold. It does have an air line for the air compressor inlet but no leaks on it that I can find. Quote Link to comment https://www.bigmacktrucks.com/topic/73048-e7-low-power-help/page/3/#findComment-536762 Share on other sites More sharing options...
fjh Posted August 11, 2023 Share Posted August 11, 2023 2 hours ago, Dtech said: Thanks FJH for your advice, However I am a little loss on the FAC I know the older mechanical injection pumps had them. I can not find anything like that on this pump? It only has wires going into the back of it. It has no lines from the intake manifold to the injection pump. It also does not have a Boost psi sensor that I can find only intake air temp that is also the only sensor that is in the manifold. It does have an air line for the air compressor inlet but no leaks on it that I can find. Well My Bad I think I was looking at something and posting to another! you obviously have VMAC and joes posted the spec there that is the correct stuff except the HP which may change the timing! and Maybe the Cam key I don't remember! anyway I'm going to stop posting I think ! I'm getting tired of chewing on shoe leather and my foot is getting sore!🙃 Macpro or someone may have some answers here! 1 Quote Link to comment https://www.bigmacktrucks.com/topic/73048-e7-low-power-help/page/3/#findComment-536769 Share on other sites More sharing options...
Joey Mack Posted August 11, 2023 Share Posted August 11, 2023 FJH. It's hard to keep all of that knowledge under control... Just sayin'. 😉... Jojo 1 Quote Link to comment https://www.bigmacktrucks.com/topic/73048-e7-low-power-help/page/3/#findComment-536772 Share on other sites More sharing options...
fjh Posted August 11, 2023 Share Posted August 11, 2023 4 hours ago, Joey Mack said: FJH. It's hard to keep all of that knowledge under control... Just sayin'. 😉... Jojo All good bro! Quote Link to comment https://www.bigmacktrucks.com/topic/73048-e7-low-power-help/page/3/#findComment-536808 Share on other sites More sharing options...
Dtech Posted August 15, 2023 Author Share Posted August 15, 2023 Has anyone ever had a Ecm being the root cause of low power? I do not think it is the issue but maybe it is? I wish I had a test ECM or maybe I could sent it to someone and see how it ran on there truck? Quote Link to comment https://www.bigmacktrucks.com/topic/73048-e7-low-power-help/page/3/#findComment-537011 Share on other sites More sharing options...
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