Loctite 243 on exhaust nuts?

Anybody using loctite 243 on exhaust nuts?

Sometimes those nuts are hard to break loose.

Why not just safety wire? No holes need be drilled.

"Why not just safety wire? No holes need be drilled."

+1 Safety wire is your best friend!

Its a known taboo to use factory lock tabs or safety wire long term as they don't help hold torque fixed just keep em from coming off on the fly, so leave loose threads beating themselves to dust. I have settled on Milk of Magnesia myself now on all my exhaust fastener needs lawn mower headers to Norton. Serious torque or spring tension retainers is about only way to go with factory set up. About anything will work though as long as helps prevent galling in and out and don't just melt and flow away. Tightness is Rightness here.

Get engine hot, tighten nuts.

powerdoc said:

Anybody using loctite 243 on exhaust nuts?

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An old favourite thread. I use neverseize on the threads, an aluminium/asbestos crush washer and tighten with a 1 foot long bar. Tighten like a spark plug. Tighten again when hot several times over a few weeks. No lock wire, no tab washers, no problems.

There used to be a special long "C" spanner (wrench to you colonials) that was about 12" to 15" long. Tighten them like Nortiboy said.
cheers
wakeup

"ts a known taboo to use factory lock tabs or safety wire long term as they don't help hold torque fixed just keep em from coming off on the fly, "

Well, I can't agree with all the words of that statement and neither would the aviation industry or the various racing organizations. Safety wire is used for precisely that purpose - to ensure a properly torqued fitting stays that way under the stress of vibration.

However, I do agree that safety wire will not keep a specific torque on a fitting that has a gasket that can further "crush" in operation - like the exhaust fitting, especially if multiple gaskets are used. Basically , I agree with both techniques with the exhaust. Tighten them as noted - engine hot, plenty of torque and then safety wire the nuts. I have had loctited (both blue and red) items fail on the Commando. Never had a safety wired fitting do so and can't see how it is possible that it could. Though if the fitting loosens, the safety wire will have to break which is visually obvious.

The only disadvantage to SW is the fact that it takes additional time to break/remake a fitting and, of course, if not already done, you have to drill the fasteners to accept the wire.

Oh...one other disadvantage: you have to be very careful to pick up any pieces of safety wire after attaching/cutting or removing. The safety wire bits seem to gravitate toward tires! Good safety wire pliers have a rubbery insert that holds onto wire bits as you cut so little pieces don't drop on the floor.

Duh exhaust rings are famous for crushing down over time-heat-vibes anything but hardened washer-spacers, if they are used, so safety wire will not take up the slight slack that can develop and slowly beats the alloy threads to dust. If you or any one has not had trouble from safety wire or lock tabs in this area then the exht. rings were put on *Tight* enough not to need anything else to retain them and safety wire is just for show or race rules and finger nicking there. Correct use of safety wire on these nuts as following aircraft practice is to wire the two nuts together so if one unlooses it tightens the other and visa versa, or springs to do similar, just takes longer runs of wire or springs as attaching to head only will not keep the clamp force up. If you ain't run into this issue to know better, just wait and see if not brave mean man enough to nip up so nothing else needed. I find the shock of sledge hammer on special ring spanner is less strain on me and Norton to really nip up for thread protection safety. Ms Peel will have plenty of safety wire but a long spring across her 'lightly' tightened alloy exhaust ring bolts.

GET IT TIGHT!
Phil demonstrates the permanent answer to Exhaust Port Thread Destruction Disorder (aka: EPTDD...I just made that up). The only way to prevent your exhaust nuts from loosening & destroying the threads is to tighten them...BIG TIME! Phil's formula: Take it for a ride & get it hot. Then get one of these long-handled exhaust spanners & tighten the crap out them! As tight as you can get them. The threads are huge, so they can handle it.

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http://www.nortonownersclub.org/support ... t-nuts-and-spanners
[url=http://www.captain.norton.clara.net/cnn3sec17.html]http://www.captain.norton.clara.net/cnn3sec17.html[/url]
[url=http://www.nortonownersclub.org/noc-chat/technical4-commando-forum/559128716/view]http://www.nortonownersclub.org/noc-cha ... 28716/view[/url]

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As I said, I agree with your comments re safety wire on the exhaust nuts and, in my younger days, I have had the pipe loosen with a safety-wired nut because I hadn't tightend the nut sufficiently and the gasket continued to "crush." Of course, the nut did not move at all. So absolutely, the nut has to be appropriately tight/gasket crushed in the first place.

The purpose of safety wire is to ensure a properly tightened (torqued) fitting stays that way. It is not there to simply keep a part from falling off though it will do that. It is still considered the best way to do the job though it is certainly not the easiest way. But it totally avoids issues with excessive torque caused by lubricating the threads with one of the loctites or other similar thread-lockers. Admittedly this isn't very critical in general applications but it can be, especially with steel fasteners (like studs) in aluminum.

I spent a lot of time in aviation and in a couple of forms of motor racing so maybe that's why I'm such a fan of safety wire...

Then we agree both by logic and by experience > safety wire on something that can loose clamp force w/o any motion of the fasteners just keeps from falling off not prevent the loss of clamp force. Where the parts are hard enough qaulity not to loose clamp force by crush over time then of course counter wrapped safety wire is the cat's meow. My P!! was art wired around engine like air craft with a single run of wire through a number of nuts and bolt heads, besides all the regular race wired items.

Absolutely right - and to sort of get back to the OP, if loctite is used that will handle the heat, the same problem can result - the pipe can loosen while the nut stays firmly locked in position.

Agree with both of you. I'd add that grabbing and shaking the head pipe when it is first nipped up helps it and the gasket to settle squarely and thereby to ensure a good bind. And, no need to drill holes anywhere; I loop the wire around one of the lower fins on the nut and the run the wire up to the lower valve cover nut. Just remove the valve cover nut to release the safety wire and then re-use it. My nuts never get too loose - lol.

Loctite is a great product but it is not effective on something super hot like an exhaust pipe. in fact, way to remove loctited parts is to get them hot.

I would stick with lock wire (practice is important).

If you tired pink coating of Milk of Magnesia ya may never go back.

hobot said:

If you tired pink coating of Milk of Magnesia ya may never go back.

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Doesn't that make your tongue go pink??? :lol: :lol: :lol:

Well yeah when I lick the threads but it don't last that long but as the red dye can cause neurological static i prescribe the white versions for looseness or over tightness in human exhaust outlets.

https://www.google.com/#q=milk+magnesia ... anti+seize