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Tightening camshaft cap bolts after valve adjustment. Followed service manual TO THE LETTER. Torqued cap bolts in specified sequence to half torque then set wrench to full 8.5 ft/lbs. Bolts seemed to be turning forever and now one has snapped. GREAT! What the hell happened? Really can't figure it out. Definitely feeling some DIY pain here.

I know two of the bolts are longer but I was extremely careful to put them back as they came out.

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you snapped a bolt pulling 8.5? humm that sucks man, dont think you did anything wrong. How did the bolts feel coming out?

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8.5 ft lbs aint shit. you probably passed that before using your torque wrench and then kept going. Or are they stretch bolts by any chance and should be replaced every time?

Anyway good luck. I hate when that stuff happens

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8.5 ft lbs aint shit. you probably passed that before using your torque wrench and then kept going. Or are they stretch bolts by any chance and should be replaced every time?

Anyway good luck. I hate when that stuff happens

Used torque wrench right from the start. Wonder now if someone over-tightened then before. This blows.

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8.5 ft. lbs. is easy to make just by twisting your wrist, it certainly won't break a 6mm bolt. I'm guessing your torque wrench is out of whack and you trusted it blindly.

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8.5 ft. lbs. is easy to make just by twisting your wrist, it certainly won't break a 6mm bolt. I'm guessing your torque wrench is out of whack and you trusted it blindly.

x2 , unless you had it calibrated lately , you have no idea what your actual torque is , yes even on a new one.

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8.5 ft. lbs. is easy to make just by twisting your wrist, it certainly won't break a 6mm bolt. I'm guessing your torque wrench is out of whack and you trusted it blindly.

It is a new wrench 'cos my existing one won't go below 20ft/lbs. Really didn't seem very tight before it snapped. There is a small amount protruding above the head so I might be able to get it out.

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x2 , unless you had it calibrated lately , you have no idea what your actual torque is , yes even on a new one.

tru dat tru dat!!!!

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I thought those bolts were measured in Inch/lbs??

edit - just checked my manual, it is 8.5ft/lbs.

I'm guessing your torque wrench doesn't go down that low? I had a hard time finding one that went that low..

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Usually you need a 1/4 drive torque wrench for that little stuff. They use inch pounds, but it's eay to convert, just multiply by 12: 8.5 ft./lbs. x 12 = 102 inch pounds.

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Well, got the snapped-off portion of the bolt out. Ground down the jagged, protruding portion with Dremel tool, pre-drilled into the top and used an extractor bit. Could not believe how easily it came out - was expecting it to be jammed in there pretty good. Hope to be back on the road this weekend.

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Good, you got lucky! Make sure to take out the other bolt and toss it out as well, it's gonna be stretched as hell.

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The reason your bolt snapped was that you put too long a bolt in a shallow hole and it bottomed out. The cam cover uses two different lengths of bolts and you must be careful on tear down to note which bolts go where. I use a piece of cardboard and push them through in the same pattern that they came out.

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Even if it bottomed out it still should have torqued, double check the wrench, make suire you were using the right scale. :busted:

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Those 6mm bolts stretch and break all the time, even with a good torque wrench. Just normal metal fatigue. Really common on CRF oil filter bolts. Every time you pull them look for stretching. Now that you know what it feels like while a bolt is stretching, remember that feeling and don't snap them off. Might want to keep extra bolts on hand, that's what I do with our CRF oil filter bolts.

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Those 6mm bolts stretch and break all the time, even with a good torque wrench. Just normal metal fatigue. Really common on CRF oil filter bolts. Every time you pull them look for stretching. Now that you know what it feels like while a bolt is stretching, remember that feeling and don't snap them off. Might want to keep extra bolts on hand, that's what I do with our CRF oil filter bolts.

Honestly, if you are snapping oil filter bolts on a CRF you are overtightening them by a lot. All you are trying to accomplish is to snug down so the screw doesn't loosen up. It doesn't even need to be near proper torque since the o-ring is compressed by the bore to make the seal.

Average torque for 6mm bolts is 36-60 inch-pounds. You can do this with really weak wrist action.

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