i've been trying to get the heads off my car for a while now to get them reconditioned but when i started taking the engine apart I ran into a couple problems was wondering if someone could clear up some confusion for me. i watch a videos where so dude spun the crank until 3 timing marks lined up before he took off the chain, in my attempt of doing so i lined it up with the wrong timing marks and took off all 3 chains improperly. my question is does it matter what position the chains sat in before removing them or am i SoL, i was thinking if i bolt all the components back together and put the engine in TDC i would be in the clear but i'm not sure. can someone please give me some good news. thanks for taking the time to read my post !

 

You're taking the heads off so it doesn't matter because everything will need to be repositioned/aligned when you bolt it back on, just don't try to spin the crank while the heads are still on. This is a zero clearance motor and the piston WILL hit the valves.

Once you have the heads off then you're free to spin the crank to your hearts content. Set it at TDC, install the heads, install each cam with it already lined up in the correct position, install the chains/tensioners.

You need to reference the FSM for this kind of work and not just go off of youtube videos, section EM - Engine Mechanical, around page 60 or so under TIMING CHAIN. I strongly recommend you follow exact steps for all the components you're installing though, most everything you're working with will be in EM, spark plugs will be in MA - Maintenance.

https://www.nicoclub.com/infiniti-service-manuals

 

you're a life saver bro appreciate you, thanks

 

need help again, i put all the timing components back on now i can't crank the crankshaft pulley bolt to get the engine into tdc it gets stuck after rotating 180° either direction

 

at this point i've probably made every mistake there is to make hopefully my engine is still salvageable in my situation. now that i've put all the tensioners and sprockets back i turned the crankshaft bolt independent from the cams to get the mark aligned for tdc now my cams are out of time and i can't get the engine to turn 180° either way the fsm shows that the cams must be aligned a certain way before removal. can i skip the alignment or get it lined back up proper in anyway or is there anything else i can do or am i finally SoL

 

You need to set the crankshaft to TDC FIRST before you install the cams, your piston is hitting an open valve.

Remove the cams (Just back the bolts off all the way so it's not pushing any valves down, don't actually have to remove the bearing caps just leave it all 100% loose), set crank at TDC, set each cam into the correct position, tighten them once they're all in the correct position.

Hopefully you weren't putting a lot of torque on that crank nut, otherwise you may have bent a valve.