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Discussion Starter · #1 ·
Alright i have a 1991 Si b21a1 completely stock. Tore down the motor for rebuild and now on the final steps. Just went to do torque down the intake and do valve clearances but the darn thing didn't want to spin. I turned the motor so hard i ended up jumping 3 teeth on the intake. So i took it off lubricated the cam again (assembly lube of course) did timing again and torqued to a measly 5 pounds. Nothing. Ive searched and found nothing. I doubt the head is warped. Could it b the cam? Or the Distributor?
 

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Did it spin freely before mounting the head?
Are the cam caps back in the original positions?
Was the head worked as part of your rebuild?
Remove the cams and rockers and lightly tap the valve at the spring to see if they move freely, if one hangs up its likely bent.
 

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It really sounds like the valves might be kissing a piston. Other than that, maybe something is out of spec with the cam, or caps, or unlikey chance the head is a problem.

Are those cam caps the original caps that came with that exact head?
 

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Discussion Starter · #5 ·
Both intake and exhaust are at top dead center along with pistons. it spun freely before I did work on it. I could spin the crank with my hand and the exhaust spins fine too. I really doubt the valves are bent because before I tore it down the engine spun easy. The head is in really good conditions so i didn't mess with that. All cam caps are in order facing the right way. Everything is lubed and in spec. It spins great if the caps are not torqued. I just have one doubt. On the flywheel there is a white cross and a couple degrees before that there are 3 lines one with 15 on it. The 15 is for 15 degrees BTDC Right? So that would make the white cross TDC. I did my timing that way. Is that correct? If its not then im pretty sure there is valve to piston contact.
 

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Discussion Starter · #6 ·
Now that i think of it my timing is on the spot because it only jumped three teeth on the intake but the crankshaft and exhaust still spun. So its definitely not timing. Probably the cam. Those caps were stuck on there when I took them off. Had to gently pry off the cam. Pretty sure that's how it got bent. Any ideas?
 

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Replace cam if its bent
 

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Oh jeeze. Stick each bolt in the holes and grab them with your hand. Now shake forward and back. That is how you remove a cam cap.

Don't play anymore games. Just replace the cam.
 

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Discussion Starter · #10 ·
Thanks guys really helps. Never removed cams from an overhead. Only Chevy's n Pontiac's. I miss driving my prelude.... :'(
 
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