Bolt torque discussion

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krazykuda said:
We used torque and angle to measure the clamp load... If we tried other oils, they would most likely fail in the multiple for angle...

We set a torque spec that we start measuring angle at, let's say 40 ft * lbs, so at 40 ft *lb the angle is now "set" to zero and we measure from there.. We would typically see angle run in the range of about 50° - 90° and we set a range that angle would be for the final torque... With "foreign oil" the angle readings would be higher and outside our angle range that was programmed in the machine...
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Makes a ton of sense... thank you!
 
krazykuda said:
That is pretty vague... It could mean anything from a light engine oil to something like penetrating oil...
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3 in 1 or sewing machine oil would be light. Apparently a specific weight or type wasn't a big deal when those manuals were written. Everything now days is so specific and nothing else will work properly.
 
toolmanmike said:
3 in 1 or sewing machine oil would be light. Apparently a specific weight or type wasn't a big deal when those manuals were written. Everything now days is so specific and nothing else will work properly.
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And some folks were still pouring babbit for bearings LOL. I am glad to have seen and used some of the older methods. I know a guy who welded up the side of a piston that had a cracked ring land and re-turned new lands in the piston.... that was in the 80's and the piston was no longer available. 1.6L engine for racing. Amazing what can work...
 
nm9stheham said:
And some folks were still pouring babbit for bearings LOL. I am glad to have seen and used some of the older methods. I know a guy who welded up the side of a piston that had a cracked ring land and re-turned new lands in the piston.... that was in the 80's and the piston was no longer available. 1.6L engine for racing. Amazing what can work...
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There's McGuivers out there everywhere. I had a customer that had a couple teeth missing off his flywheel so he fired up his wire welder and made a couple teeth. Finished them off with a die grinder to give it a basic shape and it lasted about 6 months. :BangHead:
 
I was replacing head gaskets on a ford supercoupe. New tty bolts.
Manual said engine oil as lube. Lubed threads and hydro-locked the bolts. The bolts were failing before they reached the spec.
Inspected the old bolts and they were perfect. Same lube same torque. Zero problems.
Clean thead bores and light oil.
 
toolmanmike said:
Along those same lines, it's interesting that the flex plate has 6 or 8 bolts to attach it to the crank but only 4 bolts attach the plate to the converter, and those bolts only have 4 or 5 threads. :BangHead:
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The larger bolt pattern for the flex plate to torque converter gives you more leverage, so you don't need as big of bolts to hold it as opposed to the smaller bolt pattern of the crank to flex plate...
 
Torque for a grade 5 5/16 bolt with lube is around 13 ft lbs
put in a grade 8 and torque to 13 ft lbs you get no stretch and no clamp if anything moves or gasket compresses
Install grade 8 and torque the grade 8 to 18 lbs you get more clamp but may warp something, or strip aluminum
now you could use a bottleneck stud... but why
use the right bolt
been there done that upgrade drill 60 years ago
not worth it
but use quality bolts whatever you use
I like Mopar performance SPS rod bolts
 
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