Thread lock

Nourish said:
Mick Hemmings in his video recommended putting on a little of threadlock on the big end lock nuts and then torqued to the recommended 25lb/in - now he new a thing or two about Nortons
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Sorry about this - can't help myself. Not trying to contradict the great one, but adding Locktite to lock nuts does not compute for me, and over torquing big-end bolts is a real no-no for me. Any sort of lubrication on a nut makes it easier to turn and therefore you are increasing the torque.
 
You're not wrong - I just googled it and a lubed thread requires 25% les torque - 25lb/in - 25% = 18.75lb/in.
But then he did build a lot of fine engines!
 
Whilst on the subject of Loctite - I noticed one advert stated 'Genuine' - not Chinese!
I recently bought a Loctite product thatto my suprise
was produced in China - Do Loctite manufacture in China? - I know everything else is!
 
My very limited experience with Red Loctite-
I used the red on a transmission mainshaft nut that was never to come off again in my lifetime. The factory end of that mainshaft was drilled for a cotter pin which locked the stock Castelated nut.
Because I was fitting a nonstock BNR clutch, that section of the mainshaft had to be cut off.
So with no easy proper way to lock the nut, I resorted to red loctite, which did the job.
A year later I had to take that engine apart for dynamic crank balancing.
I dreaded dealing with the red loctite, which was also on the nut holding the front pulley onto the engine crankshaft.
That nut also wasn't supposed to need to come off in my lifetime.
I had read many horror stories about struggles with fasteners welded on by some Backyard Butcher of a Mechanic who had ignorantly used red loctite.

After warming things up a bit with a heat gun, both nuts zipped off in a half second each with the 1/2" drive Ingersoll Rand pneumatic rattle gun.
What an anti-climax that was!
Even so, it was so good for me that I felt like lighting up a cigarette afterward. Unfortunately I didn't have any on hand as I don't smoke.

Glen
 
Nourish said:
Whilst on the subject of Loctite - I noticed one advert stated 'Genuine' - not Chinese!
I recently bought a Loctite product thatto my suprise
was produced in China - Do Loctite manufacture in China? - I know everything else is!
Click to expand...
Locktite is owned by Henkel company (Germany) https://www.henkel.com/
Locktite has offices around the world: https://www.loctiteproducts.com/en.html
No doubt Manufacturing wherever they get the best deal.

Permatex is a US company: https://www.permatex.com/
No doubt Manfacturing wherever they get the best deal.

The Permatex Threadlocker Blue is Equivalent to Locktite 242. It comes in liquid and gel both have the same specifications.

Locktite 241, 242 and Permtex Threadlocker Blue all have the same high temp, but differing low temps (not a factor).
 
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Nourish said:
You're not wrong - I just googled it and a lubed thread requires 25% les torque - 25lb/in - 25% = 18.75lb/in.
But then he did build a lot of fine engines!
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It's a matter of what torque damages the alloy of the connecting rod, or deforms it or causes the bolt to snap. It's probably safe to use Locktite and 25 ft lb, but I assume any engine that explodes will do it at speed between my legs that are wrapped around a gas tank! You must used new, proper nuts every time you loosen them. While true that you could reuse and hammer the locking slots, there's that engine exploding issue again.
 
  • Wow
Reactions: TBW
Never have used it inside an ICE
I am not advocating against or for the use of it.
Simply, the manuals I used and the guys that taught me never called for it, from a tiny little high revving MAC 10 go-cart engine to a 427 side-oiler 8 cylinder to Lambo's and Alfa's and Healey's and MG's and the wide variety of GM powerplants to Deutsch and Cummins diesels.
Not one ever called for thread lock internally.
You guys know how the expense of those components add up in a hurry...DFU.

Thread lock
 
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I use the 222 where I know things can come loose and never have any issues, the only time I had an issue getting anything undone was when I used some shaft fit - big mistake!
Studs I always screw in with no thread lock finger tight to avoid pulling the top thread, done this on HP air and Hydraulic systems and containment and watertight boundaries on nuclear submarines, again never come out whilst I was onboard.
 
Thread lockers have evolved considerably the last 50 years.
We normally think of Blue and Red and leave it at that.
As you can see there are several Blues and Reds.
Most buy whatever is at the local jobber, usually 242 and 271 or whatver Permatex is available.
Never thought much about it till I got my KTM.
KTM specs 243 on all internal engine fasteners on older RFS engine.
Figured they know what they where doing, went down to the local KTM shop and asked for it.
Looked at me like I had 3 heads. Finally got it a McMaster Carr.
There has to be a reason why they spec'd it and not just 'Blue'.
That's all I have other than Loctite and Permatex are owned by 'Henkel'.
Carry on.....
 
just my 2 cents,

Purple for small screws and bolts that don't require a lot of torque, but you don't want to vibrate loose. I.E. Amal carb top screws. Low strength

Blue for anything else external. Stops stuff from shaking loose and puts a protective layer on the threads to help prevent corrosion. Medium strength.

Green if you want to put Loctite on a pre-assembled nut/bolt assembly. It is a wicking medium strength Loctite. Also good if you want to Loctite a assembly that you want to torque dry.

Red, I only use it on something I don't want to take apart, or on larger bolts that can take the required dis-assemble force.

Everything else gets Anti-seize.

The reason being that both Loctite and anti-seize help prevent corrosion and galling on threads. All a part of preventive maintenance IMHO.

I also think there are a lot of different numbers for the same color because some are liquids, gels or even a paste.
 
What is the best way to remove old loctite from internal threads? Is there a solvent that works?
 
BERT said:
What is the best way to remove old loctite from internal threads? Is there a solvent that works?
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For Blue, I use a brass brush and WD40. If that doesn't work, then acetone and a brass brush.
 
Those thread chaser kits should be considered a standard tool if you’re going to be disassembling and reassembling with the same hardware. Not only do they tidy up the threads, they do a good job of getting all the old grease, grit and whatever out of the threads before you wash them.
 
1973x75 said:
Those thread chaser kits should be considered a standard tool if you’re going to be disassembling and reassembling with the same hardware. Not only do they tidy up the threads, they do a good job of getting all the old grease, grit and whatever out of the threads before you wash them.
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WITHOUT cutting threads oversize/undersize💡
 
Madnorton said:
I use the 222 where I know things can come loose and never have any issues, the only time I had an issue getting anything undone was when I used some shaft fit - big mistake!
Studs I always screw in with no thread lock finger tight to avoid pulling the top thread, done this on HP air and Hydraulic systems and containment and watertight boundaries on nuclear submarines, again never come out whilst I was onboard.
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222 has been a staple in my shop for 30 years.
Thread lock
 
And here I was thinking that Norton made those 2 counterbored crank nuts so you could fill em with wicking grade loktite ;)
 
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