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I have recently removed my valve covers to replace the gaskets and figured why not make sure all my cam caps are torqued to spec. Not thinking ahead I undid all the bolts and tried to re tighten them and low and behold they're been breaking issues, especially on the end caps. I'm not sure what I'm doing wrong here. Do I need to simply replace all the bolts to get them to be able to torque correctly? Is the Haynes manual method for torque accurate? Am I just way in over my head?
 

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If you did not torque EVENLY as you pulled the caps down onto the head, but did them one at a time, until the cap seated, you may have run into the problem described. I think.
The cam will be pushed against the seating of the caps by any valve spring that is being depressed by the cam. If that is at one end of the cam, and you start from the other, there's the whole length of the cam acting as a lever against that one cap. To mitigate that force, start all the cap bolts, and tighten then bit by bit, keeping the force and movement as equalized as you can.
89 inch/lb is about 8 ft/lb of torque. One can almost do that with a screwdriver handle if they have strong hands. I don't know the recommendation, but I think I would put some blue loctite on the threads as I assembled.
tom
 

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Couple of things...

The workshop manual spec is 72 in/lbs for the cam cap bolts. How tight are you tighteing them? Remember its INCH lbs, not foot lbs.

http://www.justanswer.com/uploads/forda ... _noise.pdf

Also, if you simply loosened the bolt then tried to retighten them, that's a problem if the cam isn't in the correct position.

If all of the intake/exhaust cams on a side are not facing the correct direction when you tighten the cam bolts, the cam will be under tension (pushing up) against the cap. This causes the cam cap to be used as a lever to try and push the cam down against the valve springs. The springs are way stronger than the bolts. At the very least you'll mess up the surface of the cam bearings. At the worst, you'll bust a bolt or two.
 

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I have recently removed my valve covers to replace the gaskets and figured why not make sure all my cam caps are torqued to spec. Not thinking ahead I undid all the bolts and tried to re tighten them and low and behold they're been breaking issues, especially on the end caps. I'm not sure what I'm doing wrong here. Do I need to simply replace all the bolts to get them to be able to torque correctly? Is the Haynes manual method for torque accurate? Am I just way in over my head?
No, you weren't in over your head, but you made it a problem by diving in 'head first'! 😵

It was not necessary, and actually not good) to remove ALL the bolts at once; that was your mistake.

(If you weren't going to closely inspect/measure the camcaps) you just needed to, one at a time, loosen a ~quarter turn to verify they would turn, but also that they weren't super loose. If everything seemed copascetic, then start tweaking them tighter, one at a time, to equalization, and then keep tweaking them one at a time to desired setting...

Likewise with replacing them.
(Unless you were actually replacing the camshaft, which I don't think either of us should do.) Only one out at a time...

Of course, if you have a broken one, then, you'll probably have to pull the cap off to turn the stub out...but only one cap at a time.

When they assemble these in factory, they have hardware fixtures that hold things in place, against the spring pressures, and custom multi-shaft pneumatic bolt-driving tools to evenly drive the bolts in, all under ~same torque, to just under the specified torque, then, it will get a final torque for the last ~2-3 in-lbs. with a more finely calibrated tool.

We don't have that option in our home garage, or even a dealer garage, so we have to pay with time...

Is that thing still running?

Best Wishes!
 
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