Timing marks question

[Gewil]

My 2011 5.7 ate the cam and lifters and I'm installing a MMX NoTuneRequired-NoSpringsRequired-MDS cam. Putting it back together and foolishly looked at the book. Timing marks all lined up and good to go. Then book says to rotate crank two revs and marks should realign. I know two revs of crank makes one rev of cam and the marks on the gears line up at 12 and 6 o'clock, but the stupid book shows chain marks also lined up. Two revs puts the chain crank single mark at about 50 degrees on the cam gear.

This turned out to be a lot bigger job than I expected and my 76 year old back is getting sore from crawling in and out of the engine compartment, I don't want to do it over.

Am I okay?


9. Rotate the crankshaft two revolutions and verify the alignment of the timing marks (1, 2). If the timing marks do not line up, remove the camshaft sprocket and realign.

 

[Brandon-w]

I think you're over thinking it. I paint markered my chain in several spots because I'm a bit of a spaz and wanted ro be 100% clear everything aligned up. I rotated the engine multiple times to be sure everything rotated and matched. All was good. The book was kinda confusing in a sense so I did it my way.

Side note: make sure the puahrods are in the lifters properly. They give a false sense of bottom I had two that were wonky. Always crank the engine by hand once your puahrods and rockers are installed. If it binds up alittle just reverse it and find the issue I pulled the rockers off fiddled with the puahrods and everything was good.
I installed a mothr thumpr it sounded amazing!
Good luck!

 

[EdGs]

Once you rotate the crank, your cam and crank sprocket marks won't line up with the chain marks for like 76 or 78 revolutions, the chain is longer on one side than the other by a link or two, AFAIK.

The only thing that will be in position are the marks on the crank sprocket should be at ~5:30 and the cam sprocket mark should be at 12:00.

 

[DILLIGAF]

Watch the MMX video it will clear everything up.

 

[Sherman Bird]

I've always been flummoxed as to WHY Chevy small block engines had the timing marks aligned with the engine at TDC compression for #6 cylinder. I mean, thinking that THIS is at #1 TDC compression would be a normal expectation.
In my early years, I'd install the distributor 180 degrees off and eventually figure out why all the backfiring when I'd attempt to start the car.
Those days are gone with the elimination of a mechanical distributor.... As to you turning the engine over after you assembled the timing chain/sprockets in time, consider the rate each gear turns in correlation to each other, and consider that it takes a full 720 degrees of crankshaft rotation to return any of the cylinders to compression TDC. Add into the fray, that the gears are different diameters and tooth count, and reasonably deduce that the timing marks CANNOT realign as shown in your depiction for many rotations.

The mechanical timing of the engine is the constant, once you have done a static timing setup. IF you did it correctly upon assembly, put it together and worry about planetary elliptical orbit, or the reflooding of the Everglades! Pax Vobiscum!

 

[Gewil]

Thanks guys! Brandon was right, I was overthinking it. Hope to get my heads back from the machine shop today and then continue assembly.

 

[EdGs]

There's 39 teeth on tensioner side, 37 teeth on guide side. 76 teeth total on chain.

So I think it takes a good many rev's before all the marks line up again (76, maybe??)

 

[crackerjack1957]

78 times

 

[crackerjack1957]

Or is it 74.......LoL