Weird thing when hand torquing new Uninstalled Spark Plugs vs Reinstalling it

[taiyou]

Don't bother reading my thread below; I will make my question simple:
Why does it only take 11 and 1/2 turn to finger tight NEW Uninstalled Plug vs 12 turns on used/already installed Plug? I tested on all 4 of the plugs to make sure it wasn't a fluke.




I know it's not difficult to change spark plugs, but it took me 3 hours and I still don't think it's at the right torque, even though it's running fine. I don't have a torque wrench, and I'm using NGK BKR5E-11 V-Power Plug(w/gasket) on KA24DE.
Reason why it took so long is that I discovered something new to myself, and I cannot find any threads about this so here it goes:

I finger-tightened the newly FRESH UNINSTALLED plug, then 1/2 turn hand torque was very smooth(felt like crushing the oil drain plug crush washer).
Then I took it out for some reason and finger-tightened but the 2nd time I tried to 1/2 turn, it was pretty stiff.

So on my 2nd new UNINSTALLED plug, I counted how many turns it takes to get it finger-tight. It was 11 and 1/2 turn. Then I did 1/2 turn hand torque; took it out, and it took 12 turns to get it finger tight the 2nd time!:confused: If you do the math, 12 turns should be right because you add 11.5 and .5=12, but this confuses me now!

So I'm not really sure if you still have to hand torque 1/2 turn on already installed/used plug?? If I were to use Torque wrench the 2nd time, wouldn't it double the torque spec? I hope this makes sense. Please help me out.

[breakindrifts]

wtf. just tighten the bitches.

why make it complicated?

[aznpoopy]

you guys got alot of time on your hands in california

if you're worried about getting torque spec right use a torque wrench. its 14-22 ft/lbs fyi

if you're normal like most people just hand tighten and leave it instead of beating the shit out of yourself over spark plugs

[camppain]

LOL don't forget to use Anti-seize also.

As stated above, just tighten them down. German torque is good, Goodandtight!

[jackjack]

wtf. just tighten the bitches.

why make it complicated?


exactly. some plugs go in smoother than others. you're thinking about it too much. just swap them in and go drive already :2f2f:

[Chrischeezer]

WOW... if ur thinking about stupid stuff like this, your going to drive yourself crazy in the near future.. good lunk

[jilo]

tighten hard, done.

[stinky_180]

your thinking about this too much

[fliprayzin240sx]

Well, unless you already crossthreaded them bitches already...

[taiyou]

I didn't cross-thread. I tested the 12 turns thing many times to make sure it wasn't a fluke. I'm a bit concerned because I don't want to cross-thread it. So when you RE-INSTALL plugs, hand-tight is enough? Or just force the damn thing 1/2 turn again even if it's super stiff? I don't care if it's not perfectly torqued, but I thought someone had the answer to this weird problem. I know most don't care, but I bet 9 out of 10 people didn't know about this:gives:

[B Love]

Just get then tight and snug and your fine.

[bongnak]

what you're experiencing is the compression of new washers. ngk have crush washers; when you tighten them for the first time they will feel tight and continue until its fully compressed.
Get it?

11.5 turns+ .5 turn= 12 turns on second install of same plug.... hahah .5 being the washers loss of thickness after first compression

hahaha all good tho kinda funny dont worry about it, but I knew a guy who had a spark plug punch through the hood on his s14 sr

[taiyou]

what you're experiencing is the compression of new washers. ngk have crush washers; when you tighten them for the first time they will feel tight and continue until its fully compressed.
Get it?

11.5 turns+ .5 turn= 12 turns on second install of same plug.... hahah .5 being the washers loss of thickness after first compression

hahaha all good tho kinda funny dont worry about it, but I knew a guy who had a spark plug punch through the hood on his s14 sr

Ok, so for the final question, would you still hand torque 1/2 turn like you're supposed to on the 2nd re-install or leave it finger tight? And thanks for actually posting some helpful information.

[bongnak]

finger tight? never!- just torque it to the manufactuers spec-

[SILEIGHTY_DET]

one grunt with a 3/8 drive wrench . not two grunts , just one . good luck

[EJ253]

the reason you get another half of a turn with used plugs is simple.

the gaskets are already squished.
new plugs have fresh gaskets.