+1 glum
Noob question: Tightening Drain Plug
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Originally Posted By: ARCOgraphite
Torque a drain plug - thats funny. Torque a cam box bolt, thats NOT funny.
+1.
Just get the thing nice and tight without putting gorilla-level torque on it.
It isn't that critical that it be torqued to spec, only that it be tight enough not to vibrate out or leak, but not tightened to the point that the pan threads are ruined.
The OP is making more of this than it is.
I have never touched a torque wrench during an oil change, and in thirty five years, I've never had a problem.
Torque a drain plug - thats funny. Torque a cam box bolt, thats NOT funny.
+1.
Just get the thing nice and tight without putting gorilla-level torque on it.
It isn't that critical that it be torqued to spec, only that it be tight enough not to vibrate out or leak, but not tightened to the point that the pan threads are ruined.
The OP is making more of this than it is.
I have never touched a torque wrench during an oil change, and in thirty five years, I've never had a problem.
I'd say + another for glum, it's a good way to get the experience without stripping a bolt.
29 ft-lbs is nothing mystical. It's just 29 pounds on the end of a wrench 1 foot long. Water is 8 pounds per gallon. Think of lifting 3+ gallons of water (I'm imagining a 5 gallon pail, 3/4 full). For me, that would be a certain amount of discomfort in my hand.
Now apply that much force on a wrench about a foot long, and you should be good-to-go. I always liked the German torque spec: "gudensnug".
29 ft-lbs is nothing mystical. It's just 29 pounds on the end of a wrench 1 foot long. Water is 8 pounds per gallon. Think of lifting 3+ gallons of water (I'm imagining a 5 gallon pail, 3/4 full). For me, that would be a certain amount of discomfort in my hand.
I'm going to have to cut 'n past that one to my torque wrench.
I may add "1/4 turn past shear", that was a torque spec we used in the garage where I use to work.
I may add "1/4 turn past shear", that was a torque spec we used in the garage where I use to work.
Another reason why I change my own oil. I let a oil change place do it once, then when it was time to change it again. I had the hardest time getting the drain plug off, I had to manage to hold the wrench with my hand on the plug and kick on it til it broke loose. Which reminds me they also over tighten the oil filter, what a day that was.
Originally Posted By: pzev
How do you use an air wrench by "feel". That's a new one to me...
The same way some use their "calibrated arm", to sometimes over tighten and damage fasteners.
Not as much anymore, but for years tire jockeys tried to torque lug nuts with impact wrenches, using the "correct" touch of the trigger to obtain the final torque. Warped rotors, broken aluminum wheels, and overtightened/damaged/broken lug bolts were more common. I suppose liability is also a huge reason most (not all) shops do the final tightening with a torque wrench.
I suppose it's similar to using your calibrated arm, except that it probably requires even more skill to get lugnuts evenly to 100 ft. lbs with an impact wrench capable of 400 ft. lbs. +. Even torque sticks are not fool proof if not matched to your impact wrench.....so I am told.
How else would one use an impact wrench to tighten lug nuts, if not by "feel"/experience?
How do you use an air wrench by "feel". That's a new one to me...
The same way some use their "calibrated arm", to sometimes over tighten and damage fasteners.
Not as much anymore, but for years tire jockeys tried to torque lug nuts with impact wrenches, using the "correct" touch of the trigger to obtain the final torque. Warped rotors, broken aluminum wheels, and overtightened/damaged/broken lug bolts were more common. I suppose liability is also a huge reason most (not all) shops do the final tightening with a torque wrench.
I suppose it's similar to using your calibrated arm, except that it probably requires even more skill to get lugnuts evenly to 100 ft. lbs with an impact wrench capable of 400 ft. lbs. +. Even torque sticks are not fool proof if not matched to your impact wrench.....so I am told.
How else would one use an impact wrench to tighten lug nuts, if not by "feel"/experience?
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Tighten until it feels tight! If you've ever tightened a bolt before you know the difference between something feeling tight and loose, or close to torquing the head right off the bolt. But honestly, with most do it yourself oil changes you've got about 2ft max of clearance and putting too much torque onto an oil drain plug with a rubber o-ring/nylon crush washer is almost impossible. Follow the "Thread it in with your fingers" as far as you can so you prevent cross threading. My experience anyhow.
Originally Posted By: doitmyself
How else would one use an impact wrench to tighten lug nuts, if not by "feel"/experience?
Yep, it's pretty much trial and error doing that. Oops, stripped that one. Guess I'll give the next one a shorter blast. There's definitely no "feel" to an impact wrench! 700 ft-lb still feels like nothing.
How else would one use an impact wrench to tighten lug nuts, if not by "feel"/experience?
Yep, it's pretty much trial and error doing that. Oops, stripped that one. Guess I'll give the next one a shorter blast. There's definitely no "feel" to an impact wrench! 700 ft-lb still feels like nothing.
For a drain plug, I just give it a good one arm pull on a standard wrench or 3/8" drive ratchet. If you use an appropriate sized wrench/ratchet for each application, you really can feel where you're at with respect to the limit of the fastener, provided the fastener is of decent quality (at least Grade 5, preferably higher). I normally wouldn't tighten anything under 13mm with more than a 1/4" drive ratchet, and I normally wouldn't tighten anything under 17mm with more than a 3/8" ratchet. Drain plugs often have a disproportionately large head for their torque rating, so you have to be careful while using good (long) wrenches with the ones that use 17 to 19 mm heads. Cheaper wrenches are usually short enough that it doesn't matter.
I consider my sense of "feel" to be pretty good after working as a bike mechanic for a few summers, where at least half of the female threads you encounter are aluminum. Here's the big thing for beginners: use your fingers rather than gripping the wrench with a tight fist and build force slowly. If it starts to get easier to turn, stop instantly; you've already overtightened and are in the plastic deformation range. Pull it out, check the threads, and reinstall with your new-found knowledge of how the buildup to the limit felt.
I consider my sense of "feel" to be pretty good after working as a bike mechanic for a few summers, where at least half of the female threads you encounter are aluminum. Here's the big thing for beginners: use your fingers rather than gripping the wrench with a tight fist and build force slowly. If it starts to get easier to turn, stop instantly; you've already overtightened and are in the plastic deformation range. Pull it out, check the threads, and reinstall with your new-found knowledge of how the buildup to the limit felt.
Better yet, don't overtighten it in the first place. Use a torque wrench. It really is not that much extra work to do the job right. A drain plug is not the fastener to use a trial-and-error approach on. And not everyone has (1) The experience; and/or (2) The skill to go "by feel".
I pretty much start the threads by hand, and then use a wrench or ratchet/socket(3/8ths type or smaller) 'til it's relatively "snug" and proceed with no more than a quart turn with moderate force. Never all of your might, something is wrong with the plug or threads in the drain plug hole itself already if it requires that much effort; or you are just plain asking for a stripped head.
Originally Posted By: glum
Better yet, don't overtighten it in the first place.
I'm speaking generally. A drain plug probably isn't the best place to experiment, though the plug should be designed to strip before the pan. My neighbour discovered this last month, and he always used a massive 250 ft-lb torque wrench. After I showed him how to clean up the pan threads with a tap, I taught him to use a normal wrench instead, and that his 1/2" drive ratchet is also not appropriate. It's possible the threads were damaged by someone else though. He hasn't done every single oil change on that vehicle, but he had done every one in the last few years.
I don't even own a torque wrench that is appropriate for drain plug bolts. My little one goes up to 250 in-lb, and I use that for spark plugs and highly compressible gaskets such as in valve covers and transmission pans, while my big one is way too big to be used under 50 ft-lb, despite having markings down to 25 ft-lb. I'd rather go by feel on an appropriate sized wrench than trust that big thing down to the bottom of its range while not being able to feel anything due to its length. I would not consider that to be doing the job right. Of course, there must be appropriate torque wrenches available in a 3/8" socket size. I've just never felt any need to seek one out.
Besides, to me, feeling the tightness of the fasteners with your own fingers on a wrench is one of the pleasures of mechanical work!
Better yet, don't overtighten it in the first place.
I'm speaking generally. A drain plug probably isn't the best place to experiment, though the plug should be designed to strip before the pan. My neighbour discovered this last month, and he always used a massive 250 ft-lb torque wrench. After I showed him how to clean up the pan threads with a tap, I taught him to use a normal wrench instead, and that his 1/2" drive ratchet is also not appropriate. It's possible the threads were damaged by someone else though. He hasn't done every single oil change on that vehicle, but he had done every one in the last few years.
I don't even own a torque wrench that is appropriate for drain plug bolts. My little one goes up to 250 in-lb, and I use that for spark plugs and highly compressible gaskets such as in valve covers and transmission pans, while my big one is way too big to be used under 50 ft-lb, despite having markings down to 25 ft-lb. I'd rather go by feel on an appropriate sized wrench than trust that big thing down to the bottom of its range while not being able to feel anything due to its length. I would not consider that to be doing the job right. Of course, there must be appropriate torque wrenches available in a 3/8" socket size. I've just never felt any need to seek one out.
Besides, to me, feeling the tightness of the fasteners with your own fingers on a wrench is one of the pleasures of mechanical work!
Doesn't need to be torqued by superman.
Just a nice snugging.
Just a nice snugging.
Remember 29ft-lbs is the equivalent to 29 lbs sitting on a 1ft long wrench. So for a box end wrench it will be about the the force of 1 bicep curl or tricep extension at the gym, more or less depending if you a Clark Kent or Superman type.
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