AI.
Why are spark plug tools 3/8 drive?
- Thread starter qqzj
- Start date
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bcradio
Well-known member
How much rust and corrosion would you like us to factor into this chart?
I'd thought of that so it would probably best to include a correction factor by state, or salt/brine use.
Seven.
mrbill55
Well-known member
On part of of this episode of "Wrenching with Mr Bill", we see our hero with a recently acquired 66 289 2V Mustang convertible with plugs date coded from 1986 installed by a 800lb gorilla with no clue as to how to tighten a spark plug properly. 7 of the 8 came out by hand, each one in a death grip with the head they were installed in, each requiring a rather large prybar type extention to my 3/8, then 1/2, then back to 3/8 socket and extension sets. Number 8 (actually the #4 plug) awaits a new impact gun (3/8"
) as I pulled my old (20+ years) out and it was DOA...Nothing, and I do mean nothing I have in my tool chest, no combination of such, gave me the leverage and clearance to get this last, stubborn plug out......Was really hoping to not have to use the old 1/2" impact gun, but I really had no chance after 1.5 hours into a typical 20 minute job, over an hour trying to wrestle the #4 plug out from it's 37 year slumber. Worse comes to worse, I'll snap the plug, or the socket, or both......Best result is that I can at least break it loose, so I can then use a hand ratchet to wrestle it from it's place.Stay tuned for part 2 (tomorrow morning if not raining) where we see our intrepid owner go either from zero to hero, or hero to zero.
Bill S.
2ndGearRubber
Well-known member
That's impossible to produce. Too many variables. I've used an 18" 1/2 drive ratchet to break them free before.
whateg01
Well-known member
I mean, if you don't break the plug off in the head, are you really even trying?On part of of this episode of "Wrenching with Mr Bill", we see our hero with a recently acquired 66 289 2V Mustang convertible with plugs date coded from 1986 installed by a 800lb gorilla with no clue as to how to tighten a spark plug properly. 7 of the 8 came out by hand, each one in a death grip with the head they were installed in, each requiring a rather large prybar type extention to my 3/8, then 1/2, then back to 3/8 socket and extension sets. Number 8 (actually the #4 plug) awaits a new impact gun (3/8"
Stay tuned for part 2 (tomorrow morning if not raining) where we see our intrepid owner go either from zero to hero, or hero to zero.
Bill S.
Can't tell if you are being a smartass, but lets play around with this idea for a minute.
Based on widely discussed advice on how to torque your bolts, you should generaly go in stages stopping at 65-80% of max torque. This is to compensate for the co-efficient of frictino/sticktion, which you need to overcome from any single torque application.Since the co-efficient of sticktion is likely 20-35% of installation torque (sometimes, arguably up to 50%),
IE, if you torque to 20nm and STOP, it will take 20%∆ of 25nm = ∆5 = 25NM to move the bolt. So you cant apply any bolt stretch without moving the bolt, if you need to stop 25nm, first you need to stop at like 18NM then go to 25 on another single motion of the wrench.
Now, for a baseline. Lets assume it applies in reverse as well as forward, as a first approximation of "take off" torque for any applied fastener. Take off will always be 120 % to 150% (or higher...but thats another story).
For our typical 16mm sparkplug, installation is ±25nm this is going to be 30 to 40NM take off range, which is technically viable for 1/4 drive.
However, let us not that in particular, AFAIK you cannot remove a plug wiht 1/4 deep sockets (even if you own them in 16mm), so this is all specalty hardware at this point. Only people that need or benefit from buying special application sockets (really) need worry about this.
Everyone else can just use regular 3/8 sockets or plug sockets if they have issue with removal of plugs without them.
turnthewrench 2.0
Well-known member
You need to watch Scotty, dude. He's the master of torque vocalizations.
mrbill55
Well-known member
I've been there before, with cheap hand tools no less, still, Amazon delivered the previously mentioned impact gun, I'm attempting to garner enough motivation to go out in the 82 degree, 70 percent humidity with the remaining light outside slowly waining to attempt to wrestle the offending sparkplug from it's current residence....However, short of installing a quick disconnect on the new tool, and a quick oiling of the same, I'm sticking with my early morning attack plan. Only time will tell whether this will be as effective as I am hoping. Stay tuned to this channel for the results, good or bad.
Bill S.
2ndGearRubber
Well-known member
Lassen Forge
Well-known member
The First time I had to do one five of those freaking plugs on ONE of those damned Ford Triton motors, I bought the plug removal tool from Lisle. That blue box for a while was my little money maker... but what an all out CRAPPY design. I hope the engineer who put that out there has daily hemorrhoids from shitting spark plug parts...
BTW all my plug tools until recently were 3/8" drive. Access issues made me get 1/4" plug tools, but yeah, they've ALWAYS been 3/8".
BTW all my plug tools until recently were 3/8" drive. Access issues made me get 1/4" plug tools, but yeah, they've ALWAYS been 3/8".
Hohn
Well-known member
I moved my 1/4 drive stuff to another drawer to get it out of the way of the tools I actually use.
Garcky
Well-known member
Yup. Me, too.
mrbill55
Well-known member
When we last left our intrepid Mustang owner, he had spent 1+ hours in an attempt to remove the #4 spark plug from a 289 powered, 1966 Mustang convertible. With the delivery of his new 300/ft/lbs, 3/8" impact driver, and a good nights sleep, he dove in to what could have been the fight of his life. Did he go from zero to hero, or hero to zero this morning. We will let the picture speak for itself.
It fought the power of the impact gun from the lowest setting, to the highest before it started to budge, once broken loose from it's long slumber, it did not stand a chance, and was successfully removed, and in one piece no less. New spark plug installed in 90 seconds, and the car is now one step closer to being back on the road after being rescued from it's long hibernation.
Bill S.
PS: Back on track for the thread itself, the 1/2" drive would not fit in the tight confines of this area of the engine compartment, and I actually snapped a Craftsman 1/4" socket by hand, for the same, so the 3/8" drive set was the perfect "medium" solution, and thankfully, it worked.
It fought the power of the impact gun from the lowest setting, to the highest before it started to budge, once broken loose from it's long slumber, it did not stand a chance, and was successfully removed, and in one piece no less. New spark plug installed in 90 seconds, and the car is now one step closer to being back on the road after being rescued from it's long hibernation.
Bill S.
PS: Back on track for the thread itself, the 1/2" drive would not fit in the tight confines of this area of the engine compartment, and I actually snapped a Craftsman 1/4" socket by hand, for the same, so the 3/8" drive set was the perfect "medium" solution, and thankfully, it worked.
ChevyEFI
Well-known member
I started with 3/8"; it's what Dad had mostly.
Then I used it mostly for a few years.
Then I used 1/4" far, far more.
Now, I've avoided 3/8" for years.
When you have everything in 1/4" and 1/2", you really only need 3/8" because an available tool is that drive size.
I have seen way too many people complain about plugs on vehicles that require nothing more than extensions and wobble, or roto ratchet. Or with headers, a dedicated socket.
When Ko-Ken doesn't make a socket, you can find the thread to be troll bait.
Or leaning over getting your gut pierced by a radiator. NBD.
whateg01
Well-known member
You need to work on more vehicles then.
Drunk posting be like.
He just drunk posting. His entire thread is contrary to life.
Ricky Joe
Well-known member
My guess is because if it was 3/7” drive then a whole range of drivers would have to be created to accommodate spark plugs. If you have to ask the question, you have to accept the answer.
When I decided to start upgrading my box from mostly USA Craftsman to higher end tools, I started with 1/4" because that's what I use and enjoy using the most. I love having good 1/4" drive tools, and a good selection of tools makes working on cars so much easier.
Next on the list is 3/8", which I do use as much as 1/4", but its usually attached to a cordless ratchet. 1/2" is rarely ever used, even though I do have quality stuff.
I am also the weird guy who uses SAE ten times more often than metric, so take everything I say with a grain of sale.
Don't you mean oil pan bolt?
ChevyEFI
Well-known member
Stubby handle ratchet snugged by hand works.
It's a shame the earlier 2v models were half-threaded.Been there, still have the tool in my "hope I don't ever need that again" drawer.
Heard they make a special one for Ridgelines
ChevyEFI
Well-known member
I am holding my breath for the one they will undoubtedly make for the Hummer truck / Silverado EV.
visionguru
Well-known member
Not torque, but socket size and extension sturdiness makes 3/8 the natural choice for spark plugs.
Most common spark plugs are of 14mm, 16mm, 18mm. Only 14mm is borderline appropriate 1/4 socket size.
Spark plugs are often way down the hole, thus extensions/U-joints are often needed. 1/4 extensions are too thin and will twist/flex easily.
Here is an example. When I was replacing the engine mount, the bolt was about 50 ft-lb. I thought my Snap On 3/8" extra long rachet (17" long) should take it out easily. BUT there was a huge amount of twisting on the 12" long 3/8 extension, which made me uncomfortable to pull the racket any further. 1/2" was more appropriate.
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This is why I like the Snap-on 1/4" ratchets with 3/8" mechanisms.
And why I use them on things like Spark Plugs.