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Bored today and tried an experiment
- chanlon1
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- Location: Belfast
Bored today and tried an experiment
Replaced my rocker cover recently and had all the old head bolts left over as they are deemed single use.
Decided to see how much you could torque them before they snapped.
When installing new ones on the engine, they say to torque to 7nm, leave 30 minutes and then turn further 90 degrees.
Assuming my old ones were slightly stretched already, I know they weren’t as strong as new ones, however on more than enough of them, as soon as I got to 13nm, they snapped.
12nm and they were fine, 13nm they snapped.
Not highly exciting but killed the time in between rain showers…..
Decided to see how much you could torque them before they snapped.
When installing new ones on the engine, they say to torque to 7nm, leave 30 minutes and then turn further 90 degrees.
Assuming my old ones were slightly stretched already, I know they weren’t as strong as new ones, however on more than enough of them, as soon as I got to 13nm, they snapped.
12nm and they were fine, 13nm they snapped.
Not highly exciting but killed the time in between rain showers…..
E86 Z4 Coupe 2006 Silver
- 1536Z4
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Bored today and tried an experiment
I think that was a great experiment and good to know
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- Lifer
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Bored today and tried an experiment
All good, presuming your torque wrench has been calibrated recently.
7-13nm is not a lot, just over 'fully seated' so there is a huge margin for error on a less than high precision spanner.
Passes the time, though, I suppose.
7-13nm is not a lot, just over 'fully seated' so there is a huge margin for error on a less than high precision spanner.
Passes the time, though, I suppose.
All good things come to those who wait. I'm really impatient which explains a lot.
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F31 320i. Good car.
E89 20i Now fully dried
Z3 'free litre'. Project and a half. Complicated!
Mazda3 sold
Tatty old R56 Mini Cooper. Money pit!
- chanlon1
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- Location: Belfast
Bored today and tried an experiment
True - tightening to 7nm isn't much, but when you are doing this for your very first time and they say to go a further 90 degrees....paranoia kicks in very quickly that they'll snap
E86 Z4 Coupe 2006 Silver
- N4LLY
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- Lifer
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Bored today and tried an experiment
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- enuff_zed
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Bored today and tried an experiment
Were these bolts magnetic?
- chanlon1
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Bored today and tried an experiment
Nope.
Not sure what type they were, but they were very light.
E86 Z4 Coupe 2006 Silver
- enuff_zed
- Lifer
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Bored today and tried an experiment
So they would have been the alloy ones. Bears out my theory that I was ok to reuse the steel ones I had on mine
- pvr
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Bored today and tried an experiment
And now getting the snapped ones out of the block
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911-50 Black - unique spec
X5M - 575 hp of fun in a V8
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VW ID.3
Previous:
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- chanlon1
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- Location: Belfast
Bored today and tried an experiment
since they had been already used, I suspect they had been stretched to some extent, so its possible brand new ones last a bit longer than 13Nm.
E86 Z4 Coupe 2006 Silver