While going through my normal seasonal prep on the track car, inspection revealed that all critical farseners still had their paint marks lined up. While looking through the manual for that one nuts' torque spec as I dutifully clicked through each one, I was wondering if you guys bother to re-torque marked bolts?
Have you ever had a bolt that rotated still be fully torqued?
Have you ever had an aligned bolt/nut that was under torqued now?
I mean, short of damage, isn't this why we paint em?
Not exactly relevant, but I know that people will ask: Spec Miata running track days on street tires.
I likely wouldn't - though really all of my "fun" cars that i actualy work on are old enough that any paint marks have long worn off and/or those parts have already been taken apart. if the paint marks are aligned, i don't see any reason to check torque unless it's some kind of bolt that could conceivably stretch or something.
When I bought this car 3 years ago, I went through and torqed all the subframe, control arm/alignment, etc. And put a nice bright yellow stripe on it.. So I'm lucky that my car is clean and all the stripes are easily visible.
It just seems like every recommendation I see for track prep involves checking the torque with a wrench for that kinda thing so I wanted to get a feel for what others do since it seems redundant to me.
On my BMW (caged race car, although I'm only doing track days) I put a wrench on every critical suspension fastener between every event, and put enough oomph on it to make sure it's not loose. I don't actually turn the fastener, I just make sure it hasn't loosened on its own.
Having used torque seal extensively in aviation, no I don't. The torque seal's job is to tell you if the fastener lost it's mechanical grip or something else is wrong under the fastener. No crack, no problem.
Minor tangentially related story: I once had an argument with a contracted Airforce QC inspector about this topic.
His premise was that if you've torqued the fastener to spec, rechecking it has now over-torqued the nut. My argument was that the fastener shouldn't yield if it's torqued to the correct spec as the torque wrench gives prior to the fastener slipping further.
For reference the FAA is a bit ambivalent about this practice provided you're careful not to rotate the fastener in any significant manner.
After a few minutes of back and forth I told him if it that were the case I've now stretched the studs on the $40,000 propeller and he'd have to write me a non-compliance report to justify sending the 0 hour prop back to McCauley for overhaul. Apparently it doesn't matter that much.
In reply to The0retical :
Totally agree with what you wrote there. Good practical advice.
I use torque seal, and generally I'd say if it's in good shape then you are too. The caveat being a nut/bolt combination. You'd want to torque-seal both the nut side and the bolt side, and then you'd want to verify both.
