Joined: Jul 2018 Posts: 102 Threads: 33
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My torque wrench broke today, so when refitting my end caps just did them "bloody tight" not as tight as I could go but still very tight with my normal socket wrench, are there are any issues than could arise with this?
Joined: Aug 2017 Posts: 502 Threads: 13
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It is really impossible to say from your information.
My suggestion would be to wait, get another decent torque wrench.
Then refit putting new big end bolts and nylocks and tighten to 19 ft lb.
Then you should be able to rest in your bed.
Joined: Aug 2017 Posts: 1,462 Threads: 26
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Location: North Yorkshire
How do you break a Torque Wrench doing up big end caps? Nick's advice is appropriate.
Steve
Joined: Jul 2018 Posts: 102 Threads: 33
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I did it when tightening the head bolts, the spring in, the pawl suddenly split, thankfully on the last but.
Joined: Aug 2017 Posts: 2,748 Threads: 31
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Location: Auckland, NZ
The bolts are comparatively large for the light components, short stroke and modest revs. Much larger and high revving engines survive on 5/16.
Probably the main threat to fatigue failure is stretched bolts and frequent repeat tightening to a high stress, as when scraping bearings.
Torsion wrenches were almost unknown pre war.
For an ordinary 45 ton HT bolt 15 lbs/ft is recommended, adequate for a non racer.
Joined: Aug 2017 Posts: 952 Threads: 38
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If you have done them B tight you have no idea how tight. I would certainly get a new torque wrench, and new bolts and nuts. Conrod bolt failure is terminal and expensive
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Location: Darkest Bedfordshire
Neither big ends nor head nuts want to be much more than 20lbft.
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Location: Sheffield South Yorks
Car type: 1932 RN saloon
Oh dear! I am doomed. Been tightening big end bolts with my trusty ring spanner for 50 plus years. I may try my new torque wrench next time.
Joined: Aug 2017 Posts: 952 Threads: 38
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Dave, I am quite happy to tighten bolts without a torque wrench, been doing so for over 50yrs
but when giving advice like to err on the side of caution
Joined: Dec 2017 Posts: 1,160 Threads: 68
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Location: Nottinghamshire. Robin Hood County
Car type: Austin Ruby Mk1 1935
I am with you Dave. I see no point in a torque wrench when using nylock nuts as they surely grip to tight on the threads. A similar situation to whether or not you oil the threads.
John Mason
Would you believe it "Her who must be obeyed" refers to my Ruby as the toy.