mbsoutherly Posted December 23, 2020 Share Posted December 23, 2020 ive only been a diesel tech a short time. ive recently acquired the task of completing a job the previous tech started and walked out on. he had already removed the rear flywheel housing and timing gears on an MP-7 GU model Mack. im tasked with putting it all back together. how can i get the motor to TDC with no timing gears? Quote Link to comment Share on other sites More sharing options...
Joey Mack Posted December 23, 2020 Share Posted December 23, 2020 it's on the front of the cam shaft 1 Quote Link to comment Share on other sites More sharing options...
Vmac3 Posted December 23, 2020 Share Posted December 23, 2020 (edited) Here you go. Take your time and follow the service bulletins. Make sure you adjust the gear backlash properly, otherwise you will have a bigger problem other than a bucket of nuts and bolts in front of you. V Ting Gear Plate Reseal.pdf Edited December 23, 2020 by Vmac3 2 Quote Link to comment Share on other sites More sharing options...
Joey Mack Posted December 23, 2020 Share Posted December 23, 2020 i guess you need to use a dial indicator on no. 1. roll it up to find T.D.C... i cant remember if the dowel on the rear crank hub is a reference point.... ask Vmac3, or FJH. on this forum.. Jojo 1 Quote Link to comment Share on other sites More sharing options...
Vmac3 Posted December 23, 2020 Share Posted December 23, 2020 Before you do anything make sure the cam damper and gear is off and the rocker shaft is off. Set the camshaft to TDC. You will see the TDC mark on the cam, line it up with the hash marks on the #7 bearing cap. The crankshaft has 2 dots that face the 12 o'clock position and the double idler gear has 1 dot that sits between the 2 two dots of the crank at the 6 o'clock position. Once you have done that then adjustable idler gear goes on. Once you have done that put the cam gear on and verify that it is at TDC. This part is very critical otherwise the engine is going fail real fast. Make sure you set the gear backlash to .004" between the adjustable idler and the camshaft gear. Once that is set verify thast it is still at TDC. If it is then you are good to go. Put the flywheel housing on. Follow the PDF that I attached and your good to go. V Timing Gear Replacement. MP7.pdf Quote Link to comment Share on other sites More sharing options...
Joey Mack Posted December 23, 2020 Share Posted December 23, 2020 Thank you chiming in... It's been 2+ years since I did a rear gear train repair, and it was on an MP-7. I pulled the engine at the time beacause the cust. wanted rod and main bearings and an engine harness. The chassis was a GU-813 with an allison... anyway thanks again. Jojo 1 Quote Link to comment Share on other sites More sharing options...
Vmac3 Posted December 23, 2020 Share Posted December 23, 2020 No problem. That was a lot of work you did on that truck. Quote Link to comment Share on other sites More sharing options...
Joey Mack Posted December 23, 2020 Share Posted December 23, 2020 I also did a valve adjustment... It sure was nice to be able to work on that engine, 360 degrees......In the future, I will probably not try to answer questions about MP engines , unless I'm sure of what I'm typing... Thanks again for chiming in.. Jojo 1 Quote Link to comment Share on other sites More sharing options...
Popular Post Vmac3 Posted December 23, 2020 Popular Post Share Posted December 23, 2020 @ JoJo Its okay, I am not here to judge, just here to help in any way I can and learn from smart people as yourself. 3 Quote Link to comment Share on other sites More sharing options...
Popular Post Joey Mack Posted December 24, 2020 Popular Post Share Posted December 24, 2020 Thanks, It's all good... Never thought about judgment.... many people here need youre knowledge...Jojo 3 1 Quote Link to comment Share on other sites More sharing options...
Popular Post fjh Posted December 24, 2020 Popular Post Share Posted December 24, 2020 Yup for sure seems They have ran off some of the good contributors here over political crap ! we need people to fill the gaps here ! I am currently around this new stuff and see the goins on but don't work on red stuff ( HAPPY NOT TO ) just( most times) a silent observer ! In the shop right now We have a mp8 unit that came in with a miss that started suddenly! down the street from the shop ! The boys pulled the valve cover to check the valve set and one of the guys have the experience of a stuck valve sure enuff, rip the head off valve is bent and the valve next to it has a third of the valve missing! Which We have seen before with MUCH larger implications Broken liners and such! Anyway the point here is It's nice that some of the new guys to the forum put forth their input and experiences Helps everyone learn and may even save some guys Bucks to keep in business ! Quite honestly these new trucks are NOT owner opp Friendly You need All the help you can get if you own one ! Thats where we come in ! So yup! V3, Joey keep up the good work ! If we all contribute we all win in some shape or form! Us old folk Like Glenn , myself and others Will hold up our end as best we can! 😇😅 5 Quote Link to comment Share on other sites More sharing options...
Vmac3 Posted December 24, 2020 Share Posted December 24, 2020 I totally agree. I don't want to get philosophical, but it's better to help someone up than to kick them while they are down. If we all can learn from each other then it's a win win for everyone. Imagine given a bucket of bolts and a box of gear to put back together and not having any clue how and not knowing what the specs are? If the original poster of this thread were to do that then geez, imagine the catastrophe? Anyway I'm glad for your contributions and JoJos. V 2 Quote Link to comment Share on other sites More sharing options...
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