Cams lock up when caps are tightened...

[AjWit]

I just got my head back from the machine shop today, I kept the cams, rollers, and lifters with me at my house and gave them a cam-less head to save on labor costs. Its practically new; cleaned, stainless valves, viton valve stem seals, all new guides, valve job, milled, intake side milled. I went to install the camshafts today, when I snug up the cap bolts, the entire camshaft locks up and will not turn when I try and turn it from the cam gear using my hands. I used all my force and it will not budge. The cam-cap bolts and not over torqued, im barely snuging them up. If I only tighten the bolts with my finger tips, I can turn the camshaft using the gear by hand, all valves, springs, and rollers seem fine and move properly. Im using clean motor oil for lube on all caps. I included a picture of where I placed all the caps to ensure they are not out of order. The intake cam in the picture(top), is the one with the notch for the CPS. (<Im hoping that’s right as well.) Also, the cap with the arrows on them are on the correct side, I bagged each set of caps separately. Does any or all of this look correct?, any ideas as to why the cams are locked in place when caps are tightened?

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[Maas]

If its all assembled with the valvesprings, lifters, blah blah blah, its not going to turn by hand.

 

[TurboAnything]

You most likely have the 1 or more Intake and exhaust caps mixed up.

 

[l3igl3ang]

I had this happen on a ford we did it was cause we put the caps on in the wrong order. Did u put all the caps on first and snug them before tighten?

 

[Maas]

Will they rotate with a ratchet?


I believe its a 17mm socket, try and turn them with a ratchet.

 

[HIGHPSI4]

With the caps tight you are pushing the valve springs to rotate the cam. The springs are hard to push down due to their stiffness. You will have to use a wrench to rotate the cam.

 

[AjWit]

OK guys, I used a 17mm socket on the cam gear bolt and I got each of them to turn. I just thought they would turn by hand, i guess i was just thinking wrong. As I turn them they kind of "clank" into place, like a quarter turn of the gear then stops, then I pull the ratchet again and another quarter turn and "clank". Im referring to the noise of the cam jumping into place in between the lobes so its not directly contacting a valve. My only concern now is how am I supposed to get the timing right when I do the timing belt, if I cant turn the cams one tooth at a time without them wanting to turn away from the 'lobe/valve connection place'? Do I just have to show it who's boss and hold it using the ratchet? <hope that wording makes sense to you guys

 

[Rob10_99]

First off, put your engine at somewhere around 90* BTDC so you don't bend any valves.

Use two box end wrenches and hold them where they need to be, they should settle within one or two teeth. Set crank at TDC and setup the timing belt keeping the cams where they are lined up, if you need to have someone hold the wrenches for you do it.

Read the vfaq if you need any help with the install.

BLEED YOUR LIFTERS IF YOU HAVEN'T!!!

 

[AjWit]

Thanks Rob. I have not bled the lifters yet but they all seem to be depressed to the correct level. As to you saying i should be at about 90* BTDC, the timing marks on the cam gears are currently next to each other in the center of the two, barely one tooth off, im pretty sure thats what you meant, so i think im good there. Thanks to all that commented.

 

[jbramble2]

By 90 * he is refering to the #1 piston. Rotate the crank until the pistons are all down to avoid making conatct with the valves when you place the head on the block. 90* btdc just makes it easier once the head is on and you go to install the t-belt, you will turn the crank 90* clockwise to TDC.