TheSamba.com :: View topic - confusion about anti-seize

Wed Mar 09, 2016 7:45 am

Apologies in advance I am sure this has been covered ZILLIONS of times!

But I might as well as since I don't know...

Regarding torquing fasteners, is there one simple product that I should/can used on basically all fasteners - just add a few drops and be done with it, or are there different products and/or amounts for various situations with fasteners - ? In particular I am confused about anti-seize vs. lok-tite... it would seem, to my noobie mind, that these two are somewhat contradictory ......the former making sure nuts don't stick, and the latter making sure that nuts hold fast.

THANKS
ED

Wed Mar 09, 2016 7:49 am

And you are right.

Wed Mar 09, 2016 8:02 am

Yep, anti-seize helps prevent nuts and bolts from seizing, and thread locker does what anti-seize tries to prevent.....

They are not always used everywhere. And not all thread locker is the same strength....

It is best to ask for your particular application if you are unsure of what to use (or if anything should be used). :D

Wed Mar 09, 2016 8:02 am

You want one of each.

Wed Mar 09, 2016 8:19 am

dobryan wrote:
It is best to ask for your particular application if you are unsure of what to use (or if anything should be used). :D

haha.... well I am unsure about every single one :) ...I was hoping not to have to be too much of a pain by, on my 'big JX thread', having to ask for every single application --- but looks like that will be the case.

At least I just learned that I should have a tube of each: 1) anti-seize, and 2) thread-locker.... good to know this.

After a while I will probably get the 'idea' regarding what goes where.

Wed Mar 09, 2016 8:26 am

Thread locker comes in a blue and a red variety. The blue is 'medium' strength and can be removed with normal hand tools. Red is high strength and can be removed with heat or a lot of hand tool force... read up on them at the Loctitie site. :D

Wed Mar 09, 2016 8:36 am

...so can I assume that 'thread locker' is used in applications where if the bolt comes loose you're in big trouble, such as a crankshaft bolt, or timing belt tensioner, or cam shaft sprocket bolt....?

...and anti-seize would be used in less critical application which often tend to stick, such as exhaust bolts, various bracket bolts etc?

Wed Mar 09, 2016 8:59 am

epowell wrote: ...so can I assume that 'thread locker' is used in applications where if the bolt comes loose you're in big trouble, such as a crankshaft bolt, or timing belt tensioner, or cam shaft sprocket bolt....?

...and anti-seize would be used in less critical application which often tend to stick, such as exhaust bolts, various bracket bolts etc?

In general this is correct. :D

Wed Mar 09, 2016 9:08 am

epowell wrote: ...so can I assume that 'thread locker' is used in applications where if the bolt comes loose you're in big trouble, such as a crankshaft bolt, or timing belt tensioner, or cam shaft sprocket bolt....?

...and anti-seize would be used in less critical application which often tend to stick, such as exhaust bolts, various bracket bolts etc?

Do be careful about using thread locker as a prophylactic for proper torques on a bolt . Crankshaft bolts, properly torqued will not come loose. With thread locker on a crankshaft bolt (which is already difficult to remove) you may be in for trouble when you go to remove the bolt.
I really cant think of a good application for thread locker on a WBX engine..maybe the flywheel bolts..but they don't fall out of place when properly torqued. Now..brake caliper sliding pin bolts..yes..although the new bolts come with thread locker on them.

Anti-seize on exhaust hardware for sure. I like the copper anti-seize.

Wed Mar 09, 2016 9:15 am

There are various methods to prevent a bolt from coming loose due to heat cycling or vibration. Serrated washers, safety wire, spring washers, thread locking adhesives, locking nuts etc.

Not all applications require any locking method. For example many of the suspension bolts and mounting bolts are fine without any locking method. However this is with stock threads which are plated with zinc or cadmium, and not lubricated. Many ant-seize products are also lubricants. Not only do they affect clamping torque (usually increasing it due too lower friction) but they also increase the chance of a fastener loosening on its own.

Use of anti-seize on critical fasteners where it is not specified is not a good idea unless additional locking methods, or inspections are performed to ensure the fastener does not loosen.

Some fasteners are subjected to cyclical loading and vibration. This can cause them to loosen. Examples are bolts on rotating assemblies such as the flywheel and crank pulley. The CV joints are another example. In these cases a locking method is often used. The CV joints use serrated washers. The pulley bolts will often use loctite. The need for locking methods varies, and is dependent on thread friction, fastener torque. The load compared to the size of the fastener matters.

Here is an example. I have a couple of jet-ski/PWC. The engines use stainless bolts in aluminum heads. This can cause seized fasteners due to corrosion. Adding anti-seize will cause the bolts to loosen and quite quickly. This is due to the extreme vibration of the 2 stroke engine. However using low strength locite not only stops the bolts from loosening, but also slows corrosion. How? Properly and liberally applied, loctite (or other threadlocker) bonds to the threads and creates a barrier to moisture. It will not be as effective as anti-seize, but it will help. As always loctite becomes a lubricant at around 350-400 degrees F, so it can aid in fastener removal when heated.

Most fasteners come with a sacrificial coating. This coating protects the fastener from corrosion. Re-plating bolts with missing or compromised coating when re-using them will reduce seized fasteners. Using new fasteners is always an option.

Regardless, you should following the manufacturers recommendations. Torque bolts to the recommended value. Adding a bit of low strength thread locker is generally not an issue. Note that some fasteners will fatigue and break if not properly torqued. For example, under-tightening head bolts, and crank pulley bolts is a bad idea, and can cause them to break due to the repeated stresses.

Wed Mar 09, 2016 9:17 am

There is some great information in the thread below. This was sent to me by a fellow Vanagon guy a while back. Most of the really good info starts on page two.

http://advrider.com/index.php?threads/loctite.265016/

Wed Mar 09, 2016 9:21 am

Living in the north where roads get salted, sanded and sloppy I use antisieze on just about any bolt, nut or screw that is exposed to the outside environment. It keeps threads from rusting and getting packed with grit. It also really helps when you have to remove something when its really cold out. There are fasteners that arent supposed to get antisieze. Everything gets siezed up here.

As stated by others there are places not use antisieze . I dont use it on most engine related parts except exhaust studs.

Wed Mar 09, 2016 9:48 am

Christopher Schimke wrote: There is some great information in the thread below. This was sent to me by a fellow Vanagon guy a while back. Most of the really good info starts on page two.

http://advrider.com/index.php?threads/loctite.265016/

Here is a quote from that thread that was made by a Loctite employee. While on the surface it may sound like a ploy to gain sales, I have actually found what he says to be 100% true. -

Quote: Rust just like galvanic corrosion will take place when a certain set of ingredients is present.

Threadlockers are an anaerobic chemistry. The liquid or stick (if you're using a stick) lubricates the threads as you introduce a clamp load on a widget.

Anaerobic chemistries cure to a hard thermoset plastic when in the presence of active metals (rusts, tarnishes, corrodes, or holds a magnet) when air is removed.

In order for a threaded fastener to experience rust-lock between the nut and bolt, an air space between the two components must be present.

And since actual metal to metal threaded engagement is only 15 to 20% for class 2 threaded fasteners that leaves us 80 to 85% of air space.

Water loves to wick into this air space and cause corrosion. The water finds a nice comfortable home and begins to rust.

Once threadlockers cure in between the nut and bolt the water can't displace the cured thermoset plastic and cause rust.

In addition to putting the brakes on rustlock, threadlockers give you the added benefit of giveing you a predictable breakloose force and prevailing loosening force.

Galvanic corrosion happens when two dissimilar metals are present. If you remove one of the ingredients of the problem you've addressed and fixed the problem. You can either use fasteners made of the same substrate OR remove the airgap which allows the galvanic corrosion to occur. Threadlockers fill the airspace in between the thread engagement and stop galvanic corrosion.

I only recommend using anti-seize on applications that exceed the upper temperature ranges of threadlockers which is normally 300F or for the high temp products 450F. Applications on a bike relate to the exhaust system and mounting hardware.

Wed Mar 09, 2016 10:31 am

MidwestDrifter wrote: There are various methods to prevent a bolt from coming loose due to heat cycling or vibration. Serrated washers, safety wire, spring washers, thread locking adhesives, locking nuts etc.

Not all applications require any locking method. For example many of the suspension bolts and mounting bolts are fine without any locking method. However this is with stock threads which are plated with zinc or cadmium, and not lubricated. Many ant-seize products are also lubricants. Not only do they affect clamping torque (usually increasing it due too lower friction) but they also increase the chance of a fastener loosening on its own.

Use of anti-seize on critical fasteners where it is not specified is not a good idea unless additional locking methods, or inspections are performed to ensure the fastener does not loosen.

Some fasteners are subjected to cyclical loading and vibration. This can cause them to loosen. Examples are bolts on rotating assemblies such as the flywheel and crank pulley. The CV joints are another example. In these cases a locking method is often used. The CV joints use serrated washers. The pulley bolts will often use loctite. The need for locking methods varies, and is dependent on thread friction, fastener torque. The load compared to the size of the fastener matters.

Here is an example. I have a coupe of jet-ski/PWC. The engines use stainless bolts in aluminum heads. This can cause seized fasteners due to corrosion. Adding anti-seize will cause the bolts to loosen and quite quickly. This is due to the extreme vibration of the 2 stroke engine. However using low strength locite not only stops the bolts from loosening, but also slows corrosion. How? Properly and liberally applied, loctite (or other threadlocker) bonds to the threads and creates a barrier to moisture. It will not be as effective as anti-seize, but it will help. As always loctite becomes a lubricant at around 350-400 degrees F, so it can aid in fastener removal when heated.

Most fasteners come with a sacrificial coating. This coating protects the fastener from corrosion. Re-plating bolts with missing or compromised coating when re-using them will reduce seized fasteners. Using new fasteners is always an option.

Regardless, you should following the manufacturers recommendations. Torque bolts to the recommended value. Adding a bit of low strength thread locker is generally not an issue. Note that some fasteners will fatigue and break if not properly torqued. For example, under-tightening head bolts, and crank pulley bolts is a bad idea, and can cause them to break due to the repeated stresses.

Excellent overview on fasteners and I agree wholeheartedly. I would guess you are ME.

Wed Mar 09, 2016 1:30 pm

on my Bay which was used on every bad road in the Oregon outback (often at high speed) i used Blue Loctite on every fastener I could get to (or Green, which will wick into the joints AFTER a fastener is assembled)

Red is only for very high strength and usually requires a torch to get it apart

there are at least a dozen different types of Loctite threadlockers, including Purple for low strength fasteners

an engineering study from a few years ago found that typical lock washers do NOT work, so use a threadlocker - Google it and you should find it

I believe Schnorr washers are an exception and DO work - I have tested this and there is a clear difference on CV bolts - most loosening of CV bolts is IMO due to improper installation

I asked Loctite how much to modify the stated torques on fasteners for use of their products and they responded that their products did not alter torque values required

When I want to prevent galvanic action, or be sure a fastener will be easily removable, I use Optimolloy anti-seize, which does not alter torques either - there (in general) 2 types - Al and Cu bases,; the latter is for exhaust fasteners... or use Milk of Magnesia

Always consult a Technical Service Bulletin for what to do if you are not sure (and even if you are "sure")

Wed Mar 09, 2016 2:14 pm

A topic in the Bay Forum about anti seize.
http://www.thesamba.com/vw/forum/viewtopic.php?t=642550&highlight=

Aloha
tp

Wed Mar 09, 2016 2:43 pm

chase4food wrote:

Excellent overview on fasteners and I agree wholeheartedly. I would guess you are ME.

You got me. 8) So is the Mrs. MMMMMM clamping forces.... :wink: