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Discussion Starter #1
Well you live and learn, I'm about to contradict myself here (so please dismiss my posts in that thread about spark plugs as the idiotic posts they were). I think only a week or so ago I was bleeting on about how you don't necessarily need torque wrenches for most jobs.. Well folks.. I've learned the hard way and now have a different more learned opinion. Please use them, please do it, if you can get one in on a bolt and you have the spec for it, just do it, it's cheaper. Believe me it'll save you the money it costs to helicoil these things I can assure you!

Bummer.. stripped thread.. and had it helicoiled.. all is well though now so not to worry, just a little out of pocket (not much).. but.. just wanted to make sure I corrected my somewhat foolish posts earlier this week or so!

Cheers

Craig
 

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Kudos to you for the update. I figure it takes a few years of wrenching to get a feel for torques. And that is all it is, a "feel", accurate to +/- 50%. I am not knocking "feel", it can save a lot of time on non-critical bolts.
So when people on this forum pooh-pooh torque wrenches, I suspect they are old hands, underestimating the lack of feel newbies have.
Glad you got it fixed.
 

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So when people on this forum pooh-pooh torque wrenches, I suspect they are old hands, underestimating the lack of feel newbies have.
Glad you got it fixed.
Not necessarily the case in all instances, but I think you might have a point. I only use torque wrenches when it's critical (Engine assembly work where you're required to torque things in stages or torquing wheel bolts), ordinary stuff (spark plugs, oil drain, oil filter cover, etc) I do by hand until it snugs finger tight then snug no more than 1/8th turn with the smallest possible wrench. If you dont have a very good sense of mechanical sympathy...please use a torque wrench. Smaller is better for most stuff.
 

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Not necessarily the case in all instances, but I think you might have a point. I only use torque wrenches when it's critical (Engine assembly work where you're required to torque things in stages or torquing wheel bolts), ordinary stuff (spark plugs, oil drain, oil filter cover, etc) I do by hand until it snugs finger tight then snug no more than 1/8th turn with the smallest possible wrench. If you dont have a very good sense of mechanical sympathy...please use a torque wrench. Smaller is better for most stuff.

I agree... If you haven't been doing it for long it is easy to over do it. My brother is a mechanical engineer for Honda R&D in Ohio and he cringes when I'm tightening things without a torque wrench. He would always say "what's that getting torqued to?" lol. I usually look at my wrist like I'm reading a number from a torque wrench and say some random number.

On a related note: My brother also makes very good points about replacing bolts with OEM, unless you know the bolt grade and can find the same bolt. He deals with that stuff on a daily basis, and things are designed to require whatever was in there previously... I sometimes throw caution to the wind and he brings up the old "well if you get in an accident and have lower quality this and that, then those parts will fail before they were designed blah blah blah," I know he rights and makes a good point but I'll never tell him that :haha:. Obviously some bolts are more important than others, just as in torquing.
 

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Cheers

Craig
Real men share their mistakes for others to learn from.

Insecure, ignorant men HIDE their mistakes so everyone THINKS they are perfect..........

Kudos to you sir. I am sure this is one mistake you will never repeat.

Thank you for sharing.

Tim
 

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Real men share their mistakes for others to learn from.

Insecure, ignorant men HIDE their mistakes so everyone THINKS they are perfect..........

Kudos to you sir. I am sure this is one mistake you will never repeat.

Thank you for sharing.

Tim

Very well put Tim. Owning up to your mistake is much harder than running and hiding from it.
 

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Very well put Tim. Owning up to your mistake is much harder than running and hiding from it.
Mistakes? What mistakes? Men don't make mistakes! :tonquesmilie:
 
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Discussion Starter #8 (Edited)
Thanks for the words guys, just that a lot of other members may just go ahead and not use torque wrenches for important things on their cars and do what I did. I mean it's not a massive deal or anything as it's fixed but it could get expensive if it's done with the wrong bolt!

So thought I'd post this as a bit of a note of caution to others and also to correct a post I put out earlier. No issue eating humble pie every now and again! I'm here to learn. I ate humble pie on the oil subject too!

PS Timmay, wheel is cleaned up, refurbed and currently has a home as my front right with new sticker and centre cap :)
 

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Discussion Starter #10
I was tightening up a rocker cover bolt, those at the front of the engine. As you face the engine bay from the front, it was the right hand side rocker cover, the 3 bolts that hold the rocker cover on closest to the vanos, it was the bolt furthest down you need to remove the airbox to get to it. I was replacing the seals on these bolts and this was the last one I did. I knew I'd done it right away, but by then it was too late. I made some calls, and took the car to a local place (just round the corner) we had a chat and they did it for me pretty much there and then. Just went round said "yeah... I was a moron.. oops.. you got a helicoil kit?" ... guy said.... "oh it's easy done.. sure.. " and we got it sorted :) Bolts all torqued correctly now ;)
 

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Good for the soul this sort of admission.

Torque on the rocker cover bolts was important on my last car, one of the corners was thin by design and too much torque just broke the corner off. Had two 'quality' independents do this to me. The third I had painted and polished in various bits and I hated having any work done...
 

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ordinary stuff (spark plugs, oil drain, oil filter cover, etc) I do by hand until it snugs finger tight then snug no more than 1/8th turn.
And guess what...you're doing your spark plugs 100% incorrectly this way. Unless of course you're using plugs without the compressible gasket. If you are please tell me the maker/part # because any I saw had the gasket.
The gasket on the correct Bosch/NGK part is hollow aluminum and needs 2/3rds of a turn after contact with the head to fully compress. At that moment the 1/16th to 1/8th turn that you suggest would apply.
Your plugs are grossly under torqued and are a) most likely not doing their job of controlling combustion chamber temps. b) you might be getting air/fuel blow by reducing power and adding even more heat to the coil pack area and c) are in danger of having the plug back itself out due to vibration. If this happens the plug could get blown out and take a percentage of your threads with it.

Torque wrenches are $50 guys...seriously.
 

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And guess what...you're doing your spark plugs 100% incorrectly this way. Unless of course you're using plugs without the compressible gasket. If you are please tell me the maker/part # because any I saw had the gasket.
The gasket on the correct Bosch/NGK part is hollow aluminum and needs 2/3rds of a turn after contact with the head to fully compress. At that moment the 1/16th to 1/8th turn that you suggest would apply.
Your plugs are grossly under torqued and are a) most likely not doing their job of controlling combustion chamber temps. b) you might be getting air/fuel blow by reducing power and adding even more heat to the coil pack area and c) are in danger of having the plug back itself out due to vibration. If this happens the plug could get blown out and take a percentage of your threads with it.

Torque wrenches are $50 guys...seriously.

Finger tight does not mean just contact. Finger tight means turning w/e it is until I cant turn it by hand anymore. Then I tighten 1/8th or 1/4, until im satisfied. For ****s and giggles, I'll go check the plugs with my torque wrench to see if I hit 30nm.

I stated 1/8th in case someone w/o mechanical sympathy was following my advice to the letter. Id rather they undertorque and have to re-tighten than overtorque and have to get the head helicoiled.
 

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I was helping my GF's BFF's husband put plugs in his POS Saturn (for our friends across the pond, Saturn was a plastic GM product that no longer exists) and I told him to tighten them until they were snug. He's Egyptian (I'm not) and English is not his first language. So I had to explain what "snug" meant. No, I didn't use my torque wrench, I didn't know what the correct settings were. "Snug" was fine. The car literally died weeks later, but I'm sure the new plugs had nothing to do with it. ??????

On another occasion, I was helping a friend do the brakes on his Honda. My annoying neighbor walked over to be nosy and insisted that we use the torque wrench on the caliper bolts. I said no, no, I've done this a hundred times, it's fine, and he's giving me a rash of s**t about it so I hand the torque wrench to my friend and say "do it until it clicks". Well, it never clicked. He stripped that bolt clean.

Important lesson #2 - always double-check setting on torque wrench before using. Fortunately this lesson only cost us a bolt, since we didn't strip the caliper.

Ah... lessons.
 

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Discussion Starter #15 (Edited)
I was helping my GF's BFF's husband put plugs in his POS Saturn (for our friends across the pond, Saturn was a plastic GM product that no longer exists) and I told him to tighten them until they were snug. He's Egyptian (I'm not) and English is not his first language. So I had to explain what "snug" meant. No, I didn't use my torque wrench, I didn't know what the correct settings were. "Snug" was fine. The car literally died weeks later, but I'm sure the new plugs had nothing to do with it. ??????

On another occasion, I was helping a friend do the brakes on his Honda. My annoying neighbor walked over to be nosy and insisted that we use the torque wrench on the caliper bolts. I said no, no, I've done this a hundred times, it's fine, and he's giving me a rash of s**t about it so I hand the torque wrench to my friend and say "do it until it clicks". Well, it never clicked. He stripped that bolt clean.

Important lesson #2 - always double-check setting on torque wrench before using. Fortunately this lesson only cost us a bolt, since we didn't strip the caliper.

Ah... lessons.
Blimey that must have been some force on that caliper bolt! They can take a bit of a beating before snapping! I think the biggest deal with torque wrenches is when going into aluminum. I think even now I'd probably not use a torque wrench on caliper bolts (haha, watch me destroy one of those next week and eat humble pie again)... I've snapped a couple of wheel bolts before and had to take my rear brakes to bits to get the bolt out.
 

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Last time I saw a thread about a rounded off wheel bolt, the guy cut the wheel off, in bits, with an angle grinder! DIY rocks!
 

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Last time I saw a thread about a rounded off wheel bolt, the guy cut the wheel off, in bits, with an angle grinder! DIY rocks!
Cut the wheel off in bits. that is hilarious.

I too am a "feel" guy when it comes to torque. Some things should be torqued appropriately, but I also believe some people can take things overboard. I've been putting on brakes, wheels, spark plugs etc- the easy stuff since I was about 6 so I HOPE I can "feel" the correct torque. I guess I'll find out sooner or later. I hope it's later.
 

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On another occasion, I was helping a friend do the brakes on his Honda. My annoying neighbor walked over to be nosy and insisted that we use the torque wrench on the caliper bolts. I said no, no, I've done this a hundred times, it's fine, and he's giving me a rash of s**t about it so I hand the torque wrench to my friend and say "do it until it clicks". Well, it never clicked. He stripped that bolt clean.

Important lesson #2 - always double-check setting on torque wrench before using. Fortunately this lesson only cost us a bolt, since we didn't strip the caliper.

Ah... lessons.
Sometimes, if torque wrenches are left "set" for too long they go way out of spec and will do that.
 

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Have to agree with much that I've read here. I swear by torque wrenches for critical things. What's critical? Most engine parts, brakes, suspension, etc., or in other words, anything that could be dangerous or expensive if put back together improperly. There's a definite trade-off between the time spent on reassembly and the value of proper torque.

As for torquing by "feel," it does take a bit of experience to do it without destroying things. E.g., remove the M6 bolt on the upper timing cover of an M20 motor that's been DIYed and you'll more often than not find a coat of soft aluminum on the bolt. :tonquesmilie:Or even better, try to remove one of the tiny internal hex-head brake rotor screw and you'll find that many have been overtightened, leaving a stripped head (impact drivers ftw).
 
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