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Presumably, a lobe is resting on a valve follower?

Are you saying the cams won't clamp down?

 

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Yes, the lobe is pushing the cam shaft too high so i can’t seat it. Even tried slowly turning each screw to slowly push the cam down but it just gets super tight.

But what is the lobe resting on, that it will not push down?

 

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It should sit on a cam bucket, but why is the cam bucket/valve not pressing down, that is the question?

 

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Yep.

Can you lift that bucket off and make sure the shim hasn't pivoted onto its edge? It's best to use engine building grease, the red stuff that washes out after you start it up, that holds everything in place while you rebuild it.

I suppose, never thought of this before decide for yourself, rotate the engine 90 deg off TDC and all the pistons should be in the middle. If the valve now compresses then it was hitting the top of the piston. You can check that way I suppose if you don't want to take the lifter out, but really you should check it all out anyway.

PS it is recommended only use a sucker on the lifters, not magnetic tools.

 

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Oh ok, i checked some lifters and they all had their shims in the correct place, but i’ll go back and check them all. Then if that dosent work i’ll turn the engine 180°. I’ll let you know by tonight if it worked or not thank you very much. also what happenes if i do use a magnet?

yeah, doesn't need to be 90, whatever is enough to drop the pistons to be sure the valves aren't contacting them. That is all I was thinking about. But if the shims are OK and the valves are seated in the buckets OK, you don't really need to do that. I suggested, in case there was valve contact

I presume you haven't removed the valves during your rebuild? I mean, if you have, might you have mis-installed a spring?

Using magnets is 'not advised' because, in theory, it can cause the buckets to become magnetic and collect iron filings from the engine to right on top of the bucket, just where the cam lobe is rotating and contacting. I think it's possibly folklore, but it is the recommended practice from aeroengineers to avoid doing that. If you don't have a sucker cup and do use a magnet, at least avoid super strong magnets though, just someting barely strong enough for the job, and/or put someting between the magnet and the bucket so it is not in direct contact and not so strong.

 

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Ok yeah i didnt remove valves during rebuild. Also yeah i know the cam journals aren’t in place, no matter which way I turn the cam they it dosent fall into the journals, there’s always a gap, if one side of the cam is flush, the side is up 1/4 of an inch. Am I just being dumb, this is my first time dealing with any can before so i’m just making sure i don’t break anything. Ok so i just want to know what my next step is. If i make sure all the shins are in place and i even turn the motor 90° and the car still dosent fall in place(into the journals) what next?

Then the laws of physics have broken for you.

The valves will still push up on the cam lobes, so you have to press them down to seat them, but they should all jiggle into place as you fit the journals, and you just pinch the bolts up gently. There should not exist the resistance you mention.

Journal bolt torque is just 10Nm I think? (7lbf) So don't go tightening them more than that.

Chain has to be fitted and correctly timed as you tighten up the journals. Lock the chain to the cam sprockets so it does not slip during tightening (cable tie or 'special tool').

Cams need to be timed with the crank using the chain. It is an interference engine and the valves are still open within just a few degrees of TDC, get the timing out and there is a good chance you end up tightening the valves against the pistons. (Hence my suggestion to rotate off TDC so you are clear of that risk, just to check things out, you can't rotate the engine like that unless the valves are timed properly. if you rotate the engine and press the cam down. But don't bolt the journals down like that else you might bend something if you accidentally rotate the engine).

I don't 'think' there is an angle where they are all closed (pretty sure?), but the valves should compress easily with a light press, they are not truck springs, they are super light race valves.

Just don't go tightening anything up if it doesn't feel like it wants to go, it is all very low torques, in fact.

 

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"Easily" is relative of course.

The specification is 0.14" spring compression for 35lb force. But journal bolts should not feel 'super tight'. 10Nm and you're done.

 

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I get that, when i get the cam journal bolts in, they have like 1/4 inch gap befofe they would sit flush before it gets really tight. Too tight. How about i just send a picture of what i mean when I get home. I’m probably explaining wrong. Thank you for the advice tho i really appreciate it wanna figure this out.

Well, my only concern, and some of the re-edits, is to make sure I am not leading you up a path when there is something wrong I cannot see.

Anyone else please jump in!

End of the day I think you might simply be over-thinking it. Fit the cam chain correctly timed, lube and fit journals, tighten up the cam journal bolts to 7lbf, then see where we are. That is what you 'should' do so if something bad happens when you do that then it's probably already happened.

 

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Phew. Glad it was just that.