Using Threadlock

[Bruce Reader]

G'day all.

 

I remember a thread on this forum where threadlocker was used both to lock bolts and to protect threads.

 

Just a quick request regarding the use of threadlocking agents. How much ? Cover all the thread ? How much do you use ?

 

I ask this as i am in the process of resealing my gearbox (thanks again Pete for the peg sockets) and want to stop any losening of bolts but also protect the threads from corrosion that i have seen on the bolts that i have removed.

 

Rgards

 

Bruce

[Dan M]

G'day all.

 

I remember a thread on this forum where threadlocker was used both to lock bolts and to protect threads.

 

Just a quick request regarding the use of threadlocking agents. How much ? Cover all the thread ? How much do you use ?

 

I ask this as i am in the process of resealing my gearbox (thanks again Pete for the peg sockets) and want to stop any losening of bolts but also protect the threads from corrosion that i have seen on the bolts that i have removed.

 

Rgards

 

Bruce

 

 

When you need to use thread locker (don't make a habit of it everywhere - I've never seen a transmission cover loosen without it) Run a small bead of the stuff around the bolt a couple of threads up from the bottom. It will smear it self to cover a few more threads as you screw it in. Do not cover all of the threads, you'll have a mess and a very difficult to remove bolt.

[Guest ratchethack]

Bruce, I'm no Pro Mechanic, but I've been a "religious" user of threadlocker since it was first available. Not exactly sure when this was, but mid-'60's seems about right. I'd no more consider rebuilding a motor without it (of which I've done a pile) than I would run a motor without oil, but o' course, that's just me.

 

I've found that a few drops at the end of a M5 bolt will immediately run as far into the rest of the threads as needed by capillary action. When you thread the bolt in, it gets distributed over the remaining threads. Any more than 2-3 drops is wasted, IMHO.

 

Now here's where some "tough guy Biker" will no doubt scoff (while his leaking bucket o' bolts drops another poorly fastened part in the lot) because it requires an effort level he'll never achieve in his entire life: Anaerobic sealants work best uncontaminated with oil. Preparing the bolt and wotever you're threading it into by cleaning both with solvent beforehand ensures both quality adhesion and optimizes the ability of the threadlocker to provide protection against dissimilar metal galvanic corrosion. This is where Brakleen shot into a tapped hole to blast out the oil followed up with a shot of compressed air to clear and dry the hole, and a pass over the bolt threads with lacquer thinner on a clean shop towel gripping the threads makes for "solid" shop procedure.

 

Have fun.

 

BTW - I never use it on critically torqued engine internals, but externally, I can't think of a place on a motorcycle where there's machine threads that I don't hesitate to use it (OK - self-locking nuts, castellated nuts with cotter pins, drain bolts, fork caps, stuff like that being exceptions), and have never had anyhing but positive results -- as expected.

 

BAA, TJM, & YMMV

[BrianG]

Bruce, I'm no Pro Mechanic, but I've been a "religious" user of threadlocker since it was first available. Not exactly sure when this was, but mid-'60's seems about right. I'd no more consider rebuilding a motor without it (of which I've done a pile) than I would run a motor without oil, but o' course, that's just me.

I learned to use this stuff when I bought my 1972 Norton Commando. I was the only fellow in our group that didn't spend an hour re-tightening fasteners for every hour of riding.

 

I've found that a few drops at the end of a M5 bolt will immediately run as far into the rest of the threads as needed by capillary action. When you thread the bolt in, it gets distributed over the remaining threads. Any more than 2-3 drops is wasted, IMHO.

 

I have found that one decent drop smeared along the distal half-dozen threads is lots for anything under 10mm.

 

 

Now here's where some "tough guy Biker" will no doubt scoff (while his leaking bucket o' bolts drops another poorly fastened part in the lot) because it requires an effort level he'll never achieve in his entire life: Anaerobic sealants work best uncontaminated with oil. Preparing the bolt and wotever you're threading it into by cleaning both with solvent beforehand ensures both quality adhesion and optimizes the ability of the threadlocker to provide protection against dissimilar metal galvanic corrosion. This is where Brakleen shot into a tapped hole to blast out the oil followed up with a shot of compressed air to clear and dry the hole, and a pass over the bolt threads with lacquer thinner on a clean shop towel gripping the threads makes for "solid" shop procedure.

Have fun.

 

'ratchethack'........Can you spell "obsessive-compulsive???

 

I buy brake-clean by the case, and my wife wonders why there are never any Q-tips in the house!

 

For a bigger project (like resealing the transmission) where you have a great many bolts, I use a yogurt container 1/2 filled with Varsol (or similar), and throw all the fasteners in the container and shake them up, then distribute them on a towel and rub them dry all together....... this leaves the threads nice and clean. pushing a Q-tip into the threaded case-hole and "unscrewing" it from the hole leaves the case threads clean.

 

BTW - I never use it on critically torqued engine internals, but externally, I can't think of a place on a motorcycle where there's machine threads that I don't hesitate to use it (OK - self-locking nuts, castellated nuts with cotter pins, drain bolts, fork caps, stuff like that being exceptions), and have never had anyhing but positive results -- as expected.

 

BAA, TJM, & YMMV

 

Where I don't use thread-lock I use anti-seize, as at the large engine-to-frame mounting bolts. I have pulled aluminum threads out of castings where steel fasteners were used without locking compound or anti-seize, and that's not fun to fix!

[dlaing]

 

I ask this as i am in the process of resealing my gearbox (thanks again Pete for the peg sockets) and want to stop any loosening of bolts but also protect the threads from corrosion that i have seen on the bolts that i have removed.

 

I don't think anyone really answered your question about how to use the threadlocker to prevent corrosion. I am not sure what the answer is. My guess is that the threadlocker offers some corrosion protection by sealing out moisture in the contact area. Outside of the contact threads, I think the protection is minimal and anti-seize is what you need if exposed to the outside, even at the risk of the bolt loosening.

My gearbox had a few of the bolts on the inside of the gearbox come loose, which caused an oil leak.

To fix it, on the inside I used loctite (some easily removeable grade) because I feared no corrosion in the oil bath.

I forget if I used loctite or anti-seize on the outer bolts.

In your case I would use thread locker on the inside and on any bolts that have NOT shown signs of corrosion, and I would use the anti-seize on the bolts that have shown signs of corrosion, and replacing them might not be a bad idea.

[jrt]

My

Threadlock is a plastic, and does nothing to prevent corrosion.

I use 1 drop of threadlock on cleaned bolts.

Use the right kind! Green threadlock...you'll never get the fastener back off, so read the bottle before you buy it.

I love antisieze as well. When I don't use threadlock (like on sparkplugs, head bolts, etc.), I use neversieze. It's a pretty good fastener-fastener as well.

[mike wilson]

I ask this as i am in the process of resealing my gearbox (thanks again Pete for the peg sockets) and want to stop any losening of bolts but also protect the threads from corrosion that i have seen on the bolts that i have removed.

 

If you are talking about corrosion on the external bolt heads, the only way to go is replace with stainless. These will need antisieze (Copaslip or, for the very rich, the silver equivalent) to prevent corrosion between the bolt and whatever it's screwed into.

 

If you are talking about corrosion _inside_ your gearbox, you need to change the oil more frequently or use it for more than going down the shops.

 

Just a thought - sometimes the remnants of some types of threadlock can look very like corroded aluminium on a freshly extracted bolt. Are you talking about white powdery stuff on the threads of bolts that you have taken off?

[Guest ratchethack]

My

Threadlock is a plastic, and does nothing to prevent corrosion.

With all due respect to our esteemed Moderator, I beg to differ.

 

Does plastic insulation on wires do anything to prevent corrosion? I b'lieve the answer is yes, though the insulation itself has no inherent chemical oxidation inhibiting properties.

 

Loctite 242® Threadlocker http://tds.loctite.com/tds5/docs/242-EN.pdf

 

Is there a manufacturer's claim of corrosion inhibition properties? No. There won't be one on a product that acts as an insulator, which is wot I b'lieve it does.

 

What I have as the basis of my belief that threadlocker works as an oxidation inhibitor is decades of using it (including many cars, a couple trucks, many boats, and 12 motorcycles, several of which were complete or partial resto's and/or rebuilds) and the observation that it virtually eliminates corrosion that would otherwise be expected in threaded applications. Henkel Loctite 242® is the stuff I mostly use, though I also use other threadlockers that seem to work the same when used as intended.

 

Here's my observation, again -- submitted without any backup other than my own experience:

 

While there's no claim of corrosion prevention from a chemical perspective in the product data sheets, dimethacrylate ester acts as a physical barrier by filling up the spaces betwen tapped hole and threaded fastener, physically excluding air and water, thereby preventing oxidation from starting and inhibiting it from continuing. It also acts as a physical insulator inhibiting electron flow from metal to metal, decreasing dissimilar metal electrolytic chemical reaction (galvanic response). I've never seen typical corrosion that might otherwise be expected in tapped holes and on threaded fasteners where it's been properly applied. I've also never had a properly threadlocked bolt ever freeze in place -- including in many places where an unthreadlocked bolt would tend to take aluminum threads out with it.

 

That's my story, and (barring acceptance of credible contrary evidence -- I'm always open to consider wotever's out there ) I'm stickin' to it.

 

BAA, TJM, YMMV, and Bob's y'er Uncle.

[dlaing]

With all due respect to our esteemed Moderator, I beg to differ.

 

If you are talking about corrosion on the external bolt heads, the only way to go is replace with stainless. These will need antisieze (Copaslip or, for the very rich, the silver equivalent) to prevent corrosion between the bolt and whatever it's screwed into.

Is threadlocker a bad idea for stainless steel threaded into aluminum?

[Guest ratchethack]

Is threadlocker a bad idea for stainless steel threaded into aluminum?

No problem wotsoever. By my experience using it with stainless socket-head bolt replacement sets in aluminum motorcycle cases starting in the late '60's, and for the most part ever since (including everywhere stainless goes into aluminum on the Guzzi), it works like a Champ -- without a trace of either galling or corrosion as mentioned above (whether due to oxidation or dissimilar metal electrolytic action).

 

From the first paragraph of the Henkel Loctite 242® Tech Data Sheet linked above:

 

Particularly suitable for applications on less active substrates

such as stainless steel and plated surfaces, where

disassembly with hand tools is required for servicing.

[jrt]

I'll agree that threadlock will help prevent water's and air's access to a fastener, but it won't actively inhibit corrosion. Weld a piece of zinc onto your bike for that.

 

How's that for meeting you halfway...or more.

[Guest ratchethack]

Well, shiver me timbers! I do b'lieve we're in agreement then, matey!

 

Now a sacrificial zinc, say ye?!

 

Avast! Works like a talisman on every filthy rotten garbage scow across the bounding main!

 

http://www.corrosion-doctors.org/Forms-gal...c-corrosion.htm

 

Wye not a landlubber's schooner, then -- eh, me bucko?!

How's that for meeting you halfway...or more.

Aye! There be the other 'alf!! -- ARRRR!

[stormsedge]

I apply threadlock to anything that looks like it will make me crash should it leave its appointed place of duty. I use antisieze on anything that I get into fairly often. I can't remember ever using either inside an engine, but have not had one apart in several years. I occasionally apply both to the garage floor in order to make tracks on the carpet...which allows my long suffering spouse a chance to become involved in my gearhead experiments. k