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Thu Jun 25, 2015 12:10 pm

So I am about to install new spark plugs and was wondering what to torque them to? I have read online 18 ft. lbs, 22 ft. lbs, and 25 ft. lbs. The couple repair books I own give me no specs, just to tighten them but not too much. I am an admitted over tightener, and would rather not be in this case :!:

Thu Jun 25, 2015 12:20 pm

22-29 ft lbs

http://www.thesamba.com/vw/archives/manuals/withoutguesswork.php

Thu Jun 25, 2015 12:22 pm

Lots more info thru that "Technical" button at upper right!!

Thu Jun 25, 2015 4:39 pm

Who here actually uses a torque wrench on spark plugs?

I admit that I do not, on any of my vehicles. Two weeks ago I had to replace a water pump on Mrs. Cusser's Yukon while we were 100 miles away from home; I did not have a torque wrench available, so did not use one.

I've seen many ASE mechanics not use torque wrenches for lots of stuff. I did use the torque wrench a lot (but not for spark plugs) when I built my Mazda B2200 engine and my 1835cc VW engine. I believe I have four torque wrenches: a 3/8 drive old beam-type that goes to 50 ft-lb, and Harbor Freight clicker ones in 1/4, 3/8, and 1/2 inch sizes that go up to 150 ft-lbs. I've seen O'Reilly loaner tool brochure that included 1/2 inch drive torque wrench which goes to 250 ft-lb, but have never gotten that.

Thu Jun 25, 2015 4:46 pm

Well, since we're being honest....I hardly ever do, except on axle nuts.

Thu Jun 25, 2015 4:59 pm

I don't use a torque wrench on plugs, and I certainly don't torque them as tight as the Bently says. I snug them in then give a slight twist more. I would guess no more than 15-18 lbs.

Those threads are not iron, and as long as I get that washer crushed--and just a tad more, then I'm okay with that. Modern cars with aluminum heads are tightened to 13 ft. Lbs. Surely our heads are not much more rugged than that.

Tim

Thu Jun 25, 2015 7:59 pm

22 to 29 ft lbs is simply a point of reference for newbs to follow, and counts on the fact that you use a torque wrench within the proper range, say 5 to 100 ft lbs in this case, and use the proper method, which is...
-When you have a specified range such as 22-29, set your wrench to somewhere in the middle like 25.
-Grip the wrench and pull only from the knurled handle portion.
-Always pull towards yourself, and use a slow but deliberate all-in-one motion.
-No stopping and starting half way, loosen and start over if needed.
-With a common "Click" type torque wrench, stop precisely when it clicks and go no further.

However, in day to day practice for changing spark plugs I've always used the "tighten them down by hand then turn 1/8 to 1/4 turn more by feel to crush the sealing washer" method.

A new plug will have a new crush type sealing washer and you will feel it crush as you tighten, and you don't need to go much past that point at all.

Used plugs with washers that have been crushed have a much different feel and you should never go that 1/8 to 1/4 turn past hand tight.

Worth mentioning is that from 40hp engines on the spark plugs threads are cut directly in the soft aluminum heads. During normal tune-ups, which is clean and gap the plugs every 6000 miles, it is not uncommon to encounter damaged threads of some sort, whether too tight or stripped out.
They may thread in so tight it's hard to get a good feel as to what stage "hand tight" occurs, or strip out and pull threads before the gasket has crushed.

So, whenever you change plugs on a high mileage ACVW engine, be sure to be prepared for whatever comes your way in spark plug thread repairs :wink:

Fri Jun 26, 2015 5:12 am

And only remove plugs when the engine is COLD!!!!!

Fri Jun 26, 2015 7:50 am

Actually, you can remove plugs when the engine is warm (like when doing a compression check on a warm engine).

But install only when the engine is cool.

Tim

Fri Jun 26, 2015 10:12 am

Cusser wrote: Who here actually uses a torque wrench on spark plugs?

I admit that I do not, on any of my vehicles.

I've seen many ASE mechanics not use torque wrenches for lots of stuff. .

One of the first things they taught us during training in the military A school was always use a torque wrench regardless of how talented you think you are. This message was reinforced during training to become a licensed aircraft mechanic. Even now during most operations of aircraft overhaul the torque of fasteners is a buy back item which means an inspector signs off the paperwork as a witness that you the mechanic used a properly calibrated tool. Be glad that not all of us cut corners, proper adherence to methods and practices is what separates a professional from a shade tree mechanic. At home I keep and use Snap On torque wrenches. Seen far to many VW engines where every fastener was over torqued. Use a torque and you can't go wrong.

Fri Jun 26, 2015 10:19 am

I always used a torque wrench on spark plugs when I was a mechanic - but it was set to 18. 22-29 always sounded a bit too-much for me.

Fri Jun 26, 2015 10:28 am

I know it's been said a no no but I do use a tiny tiny bit of anti sieze on the threads

Fri Jun 26, 2015 11:05 am

and I'm probably wrong to use a bit of moly grease on the threads.

Fri Jun 26, 2015 12:34 pm

Hello. I'm with Glut. 22+ lbs seems excessive. 18 sounds like a sweet spot. I also being a "retired tech" have not used a torque wrench on the basics like plugs. I hand twirl them in while in the socket, snug em up with the shorty 3/8 dr ratchet and just feel the washer crush. When I had my son build my current DD bus engine I had him use the torque wrench on nearly everything, as a newby needed to "get accustomed" to this tool.
As far as lube, I have used wheel brg grease, moly grease, anti-seize, and even Milk of Magnesia from a recommendation on bobistheoilguy.com.
Hope this helps, Bill.
Over 90 % of commissioned techs will use a 3/8 air ratchet on the r&r!

Fri Jun 26, 2015 7:27 pm

Zundfolge1432 wrote: I know it's been said a no no but I do use a tiny tiny bit of anti sieze on the threads

Who says... ?.. :? ... :lol:
I know the arguments against.. but real world says different. :wink:

I anti-siezes all spark plugs I replace.. ...even on modern engines..
In fact there was a recent GM "Emerging Issue" seminar regarding that very topic..
GM claims while its not necessary using it causes no adverse problems..

So..IMO.. use it.. I do use the GM Nickle based anti sieze.. :wink:

I do agree 22-29 ft lbs.. is a bit high for a NOW old VW..... but if its in good condition will torque properly.
I as most... have that feel... 17-20 ft lbs is plenty safe for an old used VW..... nothing wrong with using the right tool for the job.

If you dont use a torque wrench .. you simply dont know what they are tightened to..

.

Sat Jun 27, 2015 9:50 am

I use anti-sieze ('er whatever correct name) on plugs with no apparent problems, and no stripped / galled plug threads yet, thank you.

If I think I have time, I always use a torque wrench even for "less-critical" fasteners, but occasionally go without on more important parts if rushed BUT I take time to tell myself, "Self - you can $%^& this up if you aren't careful".

My heads are currently torqued on via my "Armstrong" torque method and at +15k miles are just fine.

I've also routinely initially torqued elements that are supposed to get re-torqued after a short in-service period, at spec + 10% and it has worked perfectly over the years - YMMV.

I use bullet-proof beam torque wrenches...lots of the current wizz-bang click / bell / buzzer wrenches aren't worth ^&*( - my educated arm is more accurate and precise...

On the other hand, from the Ripley's Beleive It or Not file, I heard from a credible source about a commercial "shop" the other day that installed spark plugs with an IMPACT GUN...WTF?

Sat Jun 27, 2015 10:12 am

It's really important to get it right on the 1300's I stripped mine using my tire wrench but that was many years ago! I now use a torque wrench just because as the heads get older and the threads more worn they won't hold much torque! Yeah, 18-22 sounds about right to me. Try 18 or 20 ft/lbs and check them cold after having driving on the open road a good bit. If they are still tight at 18 then that is going to work! Always do plugs Cold! 29 ft/lbs is too tight! Many older 1/2" deep heads will strip out strting at about 25 ft/lbs!

Sat Jun 27, 2015 10:54 am

Dr OnHolliday wrote: I use anti-sieze ('er whatever correct name) on plugs with no apparent problems, and no stripped / galled plug threads yet, thank you. My heads are currently torqued on via my "Armstrong" torque method and at +15k miles are just fine. I use bullet-proof beam torque wrenches...lots of the current wizz-bang click / bell / buzzer wrenches aren't worth ^&*( - my educated arm is more accurate and precise...

I stressed tiny tiny amount of never seize because too much can actually act as an insulator changing the heat range somewhat. Regardless of the Armstrong method professional builders and all manufacturers continue to use Precision tooling to maintain quality control and uniformity. Concerning what type of torque wrench is best to use, look no further than the military and the defense contractors. They use Snap On, Proto,Mac, Sturdivant,mititoyo, etc. these tools are maintained by a Standards lab and calibrated to within + or - 4% which is above what is acceptable to the general public for automotive use.

I'd finish by saying that the newest digital and audio type wrenches are on par with the best micrometer (click type) torque wrenches and are available from some of the brands I listed above. I've had the opportunity to tour the Rolls Royce turbine engine overhaul facility as well as Teledyne Continental Motors one of only two manufacturers still making air cooled engines for civilian and military aircraft in the U.S today. They are using this newer technology type of wrenches. VWs are very forgiving and you could be off on the torque either way and get away with it, and you could rely on the quality tools available from harbor freight which is probably better than what people were using 20 years ago. Does any of this matter? Probably not but personally I'll err on the side of caution and make as good as I can.

Mon Aug 26, 2019 8:16 am

Speaking of over-torquing/mis-threading plugs: I have a 2Kcc with MOFOCO heads and had to retap a plug. I read some Samba blogs and others and recommend NAPA’s SEC 2125 reamer/tap M14x1.5 tool and red, sticky grease to capture the chips. The tap uses a socket instead of a square-drive — convenient. About every turn, I used a toothbrush to thoroughly clean the tool, then regreased by spinning the tap directly in the grease. Brake cleaner did a good job of cleaning up the new threads; Locktite 417 held in the (pre-cleaned) steel insert. Time-Sert makes a tap-guide (#34155) which fits NAPA’s tool and takes the guesswork out of getting the right angle to start the tap. An extra hand helps. PS: I would have used the pricier T-S kit, but their inserts, labeled M14 x 1.5, were actually x 1.25. Check inserts with a plug before using.

Mon Aug 26, 2019 1:19 pm

Cusser wrote: Who here actually uses a torque wrench on spark plugs?

I admit that I do not, on any of my vehicles. Two weeks ago I had to replace a water pump on Mrs. Cusser's Yukon while we were 100 miles away from home; I did not have a torque wrench available, so did not use one.

I retract what I posted in 2015 (above). When I installed the #2 spark plug on my 1835cc engine, and used a solid threaded insert and red Loctite on the outside threads of the insert (and never-seize on the spark plug threads), I DID use a torque wrench, and went to 23 ft lbs. And that spark plug has remained in place and working, and this was quite a few years ago.