Torque Values with Loc-tite

[RWebb]

"Our liquid anaerobic threadlockers mimic oil at the point of assembly so that you don't gall stainless of soft metals.

Suggest backing it off 10% of the dry spec value. Treat the assembly as a lubricated fastener when tightening."

- from James Adams, technical specialist at Loc-tite (Henkel)

[barney911rs]

hmm, good info Randy

[dentist90]

If LocTite sets anaerobically... how come it doesn't set in the tube??

[Peter Zimmermann]

What application are we talking about? Rod bolts/nuts go together without threadlocker, as does all of the crank case hardware, chain box hardware, etc. On an aluminum case LocTite 574 is used on case halves, and again on the cam housing to cylinder head contact point. No change in torque has ever been mentioned or discussed using 574.

In the case of threadlocker, what would we use it on that's not micro-encapsulated from the factory (P/S & M/S trans nuts, rear suspension hardware on 911s fitted with multi-link components, nylok nuts in many applications, locking copper nuts for intake manifolds, upper strut/shock nuts and countless other special and non-special fasteners. I guess what I'm asking is why should this product all of a sudden be needed when it hasn't been for the past xxx years. Just respectfully curious???

[RWebb]

the query involved generic fasteners

as to the need, it can be useful for vibration - anybody who has run VW's across the desert or on really bad roads thinks of Loctite as an elixir of the gods

[rusnak]

Porsches do not need loctite? With all due respect, they only don't need em if you don't drive em.

I've learned it's better to be safe than sorry, and I do not care if purists think it's not necessary. I'll remember the 10% reduction number, which is good to know.

Intake manifold bolts, cv joint bolts (even with the correct washers), Rennline adjustable gas pedal, front suspension mounting bolts, front swaybar mounting nuts, center console sheet metal screws, inner panel sheet metal screws, brake caliper mounting bolts, exterior thermostat "thermostat saver", sunvisor clamp screw, etc.

There are a lot of fasteners that come loose on Porsches. After a long drive, there are a lot of bolts that you just have to take a torque wrench to and check for tightness.

So this is good to know.

[dentist90]

Originally Posted by RWebb

...anybody who has run VW's across the desert or on really bad roads thinks of Loctite as an elixir of the gods

EWWW! No matter how hot and thirsty you get, don't drink the LocTite!!

[Bobboloo]

Loctite has been used for years on the cylinder studs. It serves a dual purpose. Holds the stud in the case and prevents corrosion.

[mca]

Originally Posted by dentist90

If LocTite sets anaerobically... how come it doesn't set in the tube??

Interesting ... and nobody has responded.

Good question.

[Peter Zimmermann]

Originally Posted by Bobboloo

Loctite has been used for years on the cylinder studs. It serves a dual purpose. Holds the stud in the case and prevents corrosion.

Well, of course, but that has nothing to do with this thread. Head stud installation is done to a length spec, not a torque spec.

[RWebb]

Originally Posted by dentist90

EWWW! No matter how hot and thirsty you get, don't drink the LocTite!!

What about as an endodontal rinse?

[RWebb]

"I'll remember the 10% reduction number, which is good to know."



depends on the bolt - whether the spec is dry or oiled

only a 10% diff., but I'm still not sure what P AG has spec.d

[rusnak]

I thought the convention was that all values were dry unless specified. I've been assuming the Bentley manuals were quoting dry numbers with clean threads of course.

[RWebb]

I've heard that for Porsche, and/or for German car in general. Not sure if true tho.

[JohnJL]

I was just assembling a case today and thinking the same thing about "why doesn't the 457 cure in the tube?"

[JohnJL]

Maybe it initially oxidizes and changes chemically and then becomes anaerobically curing?

[rfn026]

An engine builder once told me that if it doesn't get anti-seize then it should get Loctite.

Richard Newton

Autocross Performance Handbook

Ultimate Garage Handbook

[Quicksilver]

Originally Posted by dentist90

If LocTite sets anaerobically... how come it doesn't set in the tube??

Loctite only hardens in the absence of air (anaerobic). If you take a brand new tube or bottle of thread locker and shake it you can feel the air in the package. They never fill the packages more then halfway.

To dive farther into it:
What actually catalyzes the curing reaction is two part. It must have a lack of oxygen and be in contact with metal with active ions. Iron, non stainless steels, nickel, brass, bronze, aluminum alloys, copper, etc are all metals with active ions.

Anodized aluminum, pure aluminum, stainless steel, titanium, galvanized steel, zinc, cadmium, magnesium, chemical black oxide, gold, silver, etc are examples of metals without active ions. Most of your corrosion resistant metals or platings get their corrosion resistance from the lack of free ions. Basically most plating won't kick the curing process so it is a lot better if at least one of the exposed metals is an active metal. I have found that it will cure if you are using only metals from the "non active" list but it is pretty slow.

[Porsche_monkey]

Originally Posted by dentist90

If LocTite sets anaerobically... how come it doesn't set in the tube??

Blue loctite never seems to dry in the tube. But if you leave red loctite in the nozzle it will harden. If I let mine sit too long it has to be drilled out.

[Zeke]

I have a feeling after reading this forum for many years that if you took all the torque wrenches from everyone's tool boxes and threw them in one pile, they would differ in calibration by 10 %. What's my point? That many motors have been assembled with torque values in a range of +- 10%. And most all of them live.

Is it possible that the value given for a specific bolt/nut is a target and not an absolute? I mean the charts don't seem to take in to account ALL of the variables like different manufacturers (slightly different metal composition),etc.

Copied from the Net:

Originally Posted by
Joe Greenslade is President of Greenslade and Company, Inc. located in Rockford, Illinois. His firm specializes in providing manufacturing tooling and inspection equipment to suppliers of screws, bolts, rivets, and nuts
throughout the world.

The table in this article shows that by using this formula a 1/2-13 Grade 5 plain bolt should be tightened to 82 foot pounds, but the same bolt that is waxed only requires 41 foot pounds to tighten the same tension. A perfect 1/2-13 Grade 5 waxed bolt will break if it is tightened to 81 foot pounds because the K factor is drastically lower. The bolts are fine, but the application changed. Suppliers need to understand this and be able to educate their customers to resolve this common customer complaint about breaking bolts.

"What torque should I use to tighten my bolts?" Keep in mind this is only an estimated value. It may provide satisfactory performance, but it also may not. Every application should be evaluated on its own to determine the optimum torque value for each application. Major bolt suppliers should have tension indicating equipment necessary to help their customers determine the appropriate tightening values for their specific applications. Keep in mind that if the lubricant on a bolt and nut combination is changed, the tightening torque value must be altered to achieve the desired amount of bolt tension.