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Seized Bolts


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I'm breaking down my bike after having it been ridden hard for a while and alot of the bolts seem corroded and almost seized in there...do you grease all of them a little?

Depending on the bolt, I'll use locktite or anti-seize. Grease usually only on the shaft, like axels.

Mike

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Does it help to go to better quality bolts too?

I generally change out all of the Philip screws (like float bowl screws) with socket head cap screws.  To loosen tight screws, use the methods above and just keep working them until loosened or destroyed.

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Thanks you guys....

If you use anti-seize or any other lube on the threads then you must figure out new (Lower) torque specs when you use a torque wrench and I highly recommend you do.

I will use grease on the shafts in certain cases (engine mounts, linkage, etc.) but leave the threads dry and only oil if the OEM manual says to do so, this way all my torque values will be correct and by the book.

Edited by AXAxiom
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ALL torque specs given are for a lubricated fastener unless otherwise noted. 

 

Not.  They are for dry, clean, no rust or other crap, including lube.  I doubt lube would make a difference on torque, but torque specs are always for clean bolts.

 

"

To Lubricate or Not

Most times, the specified torque value assumes clean and dry parts. Clean means no dirt, rust, dried-up ­gasket sealer or anything except shiny metal. Wire-brushing the threads will help remove rust or sealant. Engine fasteners, like head bolts or main cap bolts, are often specified to be torqued with 30-weight engine oil wetting the threads and washer. If you're installing a fastener that has a dry torque spec, and the threads and bolt face are oiled, you'll need to reduce the torque by 15 to 25 percent, because the slipperier surfaces will decrease friction. Teflon-bearing lubes or moly-sulfide engine assembly lubes can reduce friction enough to require a 50 percent reduction in tightening torque. Even casually substituting a zinc- or cad-plated bolt or washer for an unplated one calls for, respectively, a 15 or 25 percent reduction in applied torque, because the plating acts as a lubricant. Fail to heed this advice and the fastener will be seriously overtightened. You'll either snap it or crush a gasket to the point where it leaks.

On the other hand, rust or burrs on the threads can increase friction enough that a fastener tightened to the specified value won't provide sufficient clamping force. The shop manual will specify whether the fastener is supposed to be dry or lubed. In either case, prep your bolts. Don't forget that residue from the parts washer or that pie tin full of kerosene you're using to clean parts has oil in it. Even a quick blast of compressed air to dry off a fastener will leave an oily film behind, affecting ultimate torque. If you're really fastidious, clean up with some aerosol carb or brake cleaner, followed by more air. If you've used grease or anti-seize compound to keep the brake discs from seizing to the hubs, take care not to contaminate the studs or lug nuts."

 

http://www.popularmechanics.com/cars/how-to/repair/torque-wrench-101-how-to-get-the-right-amount-of-force-2

Edited by cjjeepercreeper
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ALL torque specs given are for a lubricated fastener unless otherwise noted. 

 

I’m a licensed A&P (Airframe & Power plant) mechanic. I worked general aviation and USAir for 30+ years.

so I say BS 

Edited by AXAxiom
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