timing chain "too short"

[5Toes]

doing a head gasket job on a m42 car. m42 head is on, but alas there is a problem.

block is LOCKED into TDC postition. head is locked at TDC position as well. cam marked "E" is on the intake side, cam marked "A" is on the exhaust side.

now, the timing chain I had ziptied to the cam sprockets but no matter what I do there is just no where near enough slack to get sprockets on the cams. I undid the zipties to try and get the sprockets on but that shit didnt work so Im stuck. Not sure how the chain is a cm too short all of a sudden, Im thinking it might have a bind near the oil pump sprocket or something.

Im thinking of unlocking the bottom end and finessing a wrench on the crank pulley to try and get this "knot" out of the chain. any ideas? I would really appreciate the help. Im 100% sure the head is bolted down proper, along with the camshafts and their position, so I am not why this chain wont co-operate.

the timing guides look good, maybe 5% worn down (nothing to worry about).

any ideas? TIA

[R1dd1ck913]

Do you have any pictures.

[bmwman91]

Are the timing case covers still off of the engine?

Have you removed the timing chain tensioner piston? You don't want that in there pushing on the rail when installing the chain and stuff. SOMETHING is in there incorrectly if the tensioner piston is removed and you can't get the chain on with things at TDC.

[5Toes]

the tensioner piston is uninstalled. I believe that the chain has become bound up near the idler pulley. I am going to remove the cams, fix this chain bind problem (hopefully without removing the lower cover), and go from there.

I am hoping that if I rotate the bottom end around a little this bind will come undone.

[bmwman91]

Hmm. Yeah if you at any point turned the crank counter-clockwise then there is a very good chance that the chain jumped off of the crank pulley. The same can happen if the crank is turned the correct way (clockwise) without enough tension on the chain. Basically, it gets jammed up between the crank pulley and bottom plastic guide. You can try carefully turning the crank and pulling on the chain, but you can end up breaking the lower guide if things are wedged together enough. Bummer about the lower cover already being back on. I always put it back on after all of the timing stuff is installed (because this sort of thing happened to me once!).

[5Toes]

I never removed the lower cover, I am only performing a headgasket repair on this one. I dont mind removing the cover, its just I dont have a new crank seal to install and I really wanted to drive it this weekend!

[5Toes]

OKAY I pulled an all nighter and worked on the car until 430 in the morning in my backyard LOL. it turned out the timing chain had come off the idler pulley/wheel partially and had bound up. I pulled the cams, played around with the crank pulley and freed it up (I was SO relieved). locked bottom end back at tdc, installed cams and locked them at TDC. made sure to clock them correctly with the arrows up and then got the rest of the engine back together :)

added oil + water today and fired her up. has a terrible backfire and is running super rough. has 180psi compression acrossed the board, so I knew that wasnt the problem.

DME throws code 1214, which I believe to be the crank position sensor. the CEL flickers while running, and even if you floor the gas it will barely rev up. sometimes it idles smoothish, other times almost dies and catches itself. I diagnosed it to have an intermittent crank sensor so a new one has been ordered :)

thanks for the help guys!!!