VTS Posted February 25, 2022 Share Posted February 25, 2022 When I set the valve lash, there are other exhaust valves that seem to have waaay more clearance than they should. For example, when at the 1/6 mark on the damper for cyl 1, the 3 and 5 exh valves have a ton of clearance. Rotate crank to set cyl 5, and 2 other exh valves will have alot of clearance. I have set the valves 3 times, to the same effect. Is this normal? Is the cam different in a e7 vs em7? Thanks in advance Quote Link to comment https://www.bigmacktrucks.com/topic/69291-em7-valve-lash/ Share on other sites More sharing options...
R.E.D Posted February 26, 2022 Share Posted February 26, 2022 Damper? timing marks are at the flywheel.Clearance or lash is checked at the piston's compression stroke.if you're setting valves for 1 other valves will be in overlap . Quote Link to comment https://www.bigmacktrucks.com/topic/69291-em7-valve-lash/#findComment-490302 Share on other sites More sharing options...
VTS Posted February 26, 2022 Author Share Posted February 26, 2022 14 hours ago, R.E.D said: Damper? timing marks are at the flywheel.Clearance or lash is checked at the piston's compression stroke.if you're setting valves for 1 other valves will be in overlap . This engine has a damper that is stamped with the cylinder numbers 120deg apart. There is a pointer bolted to the block. The book says to bar the engine over to place #1 cyl to the pointer on compression stroke and set the lash. Then bar over to the next cyl in the firing order (5) and set that one, and so on thru the entire firing order. My problem is that after setting the lashes, there are exhaust valves that have more clearance than they were set for after barring the crank to the next cylinder. Like the cam wasnt at its lowest profile when it was lined up on the damper. Any thoughts? 1 1 Quote Link to comment https://www.bigmacktrucks.com/topic/69291-em7-valve-lash/#findComment-490350 Share on other sites More sharing options...
fjh Posted February 26, 2022 Share Posted February 26, 2022 (edited) If the engine is equipped with dynatard engine brake this is normal! Long as you followed the direction correctly and you had tight valves on the opposite cyl you were setting on that stroke AND you were on the valve set pointer! all is good! Edited February 26, 2022 by fjh 1 1 Quote Link to comment https://www.bigmacktrucks.com/topic/69291-em7-valve-lash/#findComment-490353 Share on other sites More sharing options...
R.E.D Posted February 26, 2022 Share Posted February 26, 2022 1 hour ago, VTS said: This engine has a damper that is stamped with the cylinder numbers 120deg apart. There is a pointer bolted to the block. The book says to bar the engine over to place #1 cyl to the pointer on compression stroke and set the lash. Then bar over to the next cyl in the firing order (5) and set that one, and so on thru the entire firing order. My problem is that after setting the lashes, there are exhaust valves that have more clearance than they were set for after barring the crank to the next cylinder. Like the cam wasnt at its lowest profile when it was lined up on the damper. Any thoughts? Is this pointer factory or did someone add it?i use the flywheel method because it's dead on..check that the pointer coincides with the flywheel markings..also not trying to scare you but if you have damaged lifter rollers ,it would throw off you lash setting when engine is rotated.... Quote Link to comment https://www.bigmacktrucks.com/topic/69291-em7-valve-lash/#findComment-490361 Share on other sites More sharing options...
Joey Mack Posted February 26, 2022 Share Posted February 26, 2022 May I suggest running these valves the Mack way and not the 'Cat' way.. I never stray from the Mack way and my valves are right and quiet... with respect, Jojo 1 1 Quote Link to comment https://www.bigmacktrucks.com/topic/69291-em7-valve-lash/#findComment-490378 Share on other sites More sharing options...
Popular Post fjh Posted February 27, 2022 Popular Post Share Posted February 27, 2022 6 hours ago, Joey Mack said: May I suggest running these valves the Mack way and not the 'Cat' way.. I never stray from the Mack way and my valves are right and quiet... with respect, Jojo Don't think he was implying to set the cat way Joe , how ever I agree hole heartedly ! 2 1 Quote Link to comment https://www.bigmacktrucks.com/topic/69291-em7-valve-lash/#findComment-490448 Share on other sites More sharing options...
Joey Mack Posted February 27, 2022 Share Posted February 27, 2022 yes sir, i understand. however, I was hoping to help him do it once.. I guess, because I am not there to see if he is up on #1 and starting on #1.. I am certainly not trying to be a,,, well you know.. always good to hear from you 'F' jojo 1 1 Quote Link to comment https://www.bigmacktrucks.com/topic/69291-em7-valve-lash/#findComment-490449 Share on other sites More sharing options...
VTS Posted February 27, 2022 Author Share Posted February 27, 2022 21 hours ago, R.E.D said: Is this pointer factory or did someone add it?i use the flywheel method because it's dead on..check that the pointer coincides with the flywheel markings..also not trying to scare you but if you have damaged lifter rollers ,it would throw off you lash setting when engine is rotated.... Pointer is factory and Im using a Mack manual. I will look for the flywheel marks to see if they are the same as the damper. I will look into the rollers... Quote Link to comment https://www.bigmacktrucks.com/topic/69291-em7-valve-lash/#findComment-490490 Share on other sites More sharing options...
VTS Posted February 27, 2022 Author Share Posted February 27, 2022 12 hours ago, Joey Mack said: yes sir, i understand. however, I was hoping to help him do it once.. I guess, because I am not there to see if he is up on #1 and starting on #1.. I am certainly not trying to be a,,, well you know.. always good to hear from you 'F' jojo No worries. Quote Link to comment https://www.bigmacktrucks.com/topic/69291-em7-valve-lash/#findComment-490491 Share on other sites More sharing options...
Joey Mack Posted February 27, 2022 Share Posted February 27, 2022 just clean the balancer.. the marks are there.. On the E-7 dont expect '0' to be TDC... 1&6 will be before that mark on the balancer.. I dont know how many degrees, but its there.. You say you have the book... great! one more thing... I was taught a long time ago how to tell if you are up on #1.. When the pointer shows 1&6, look to see if the #2 exhaust rocker is 'rocked'... if it is, you are up on 1 and ready to start running the rack. if not... go around 1 more time.. jojo Quote Link to comment https://www.bigmacktrucks.com/topic/69291-em7-valve-lash/#findComment-490493 Share on other sites More sharing options...
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