Please can someone advise me what grade of Loctite to use to lock the plugs? I have looked at the Loctite website, but it does not make it clear. None of the grades mention oil resistant.
Many thanks - Rowan
I used to teach a class on this,, The loctite website has a lot of very useful info, as well as commercial users could order a manual for the products.
Here is a rough guide for useage.:
BLUE: (#242) Most useful, when properly used will work for most fasteners and has a specific torque rating so that once you exceed that, it breaks free. For parts you might want to service or remove from time to time. I use this on most fasteners on old motorcycles. (For example the screws or bolts adjacent to the intake ports on carb manifolds... Norton 2>1 intakes, Sportster and Buell, etc etc,, Would be a catastrophe to swallow a bolt or scew in the intake) But very helpful for general fasteners that tend to loosen and fall off such as fenders, oil tank fixings, fuel tank bolts on & on.................
RED: (#271) Hardcore useage only, Semi permanent. This stuff should be used carefully as once it cures its very hard to remove that fastener. VERY useful for steel studs in alloy such as cyl base studs, or transmission cover studs. Or extra security bolts that you are very worried about ever coming loose again. To remove a properly cured red loctite fastener with just a wrench or socket likely you will round off or strip it before it loosens. BUT there is a trick,., use a small propane or gas torch and heat the fastener past 200 deg F and that will release the chemical bond.
GREEN: Green is technically a Bearing retainer compound, but I often will use it in addition for extra security as a thread locker on the exterior. So,, Bearing retainer is what it is designed for. For example layshaft bearings on a Norton GB are known for loosening. This is applied and works quite well. On some bearings as well I apply a small amount around the perimeter of an installed bearing and allow it to cure.
On sludge trap plugs I use blue on the threads and a few small drops of green around the edge of the plug. On connecting rod bolts, I torque and do all my procedures and while most rod bolts are SUPPOSED to be self locking I will apply a small film around the threads protruding from the rod nut as extra insurance. So as a retaining compound it kind of glues things in place.
( OEM specified. A low viscosity threadlocking liquid that wicks along the threads of preassembled fasteners to secure them in place. Since it is applied after assembly, preventive maintenance procedures are simplified. Ideal for fasteners ranging from #2 to 1/2" (2.2 to 12mm) in size. Localized heating and hand tools are needed for disassembly. Conforms to ASTM D5363 AN0261 (Mil-S-46163A, Type III, Grade R).)
There is other Loctite products but thats the ones I keep in a small tray above my workbench and use religiously.
The key here is that the threads and application area MUST be clean and free of oil residue when applied. Any oil or petroleum residue (or Olive oil for that matter, or your grubby hands WASH THEM!) can contaminate the bonding that loctite does. Its basically formulas of super glue and to cure it has to do its chemical reaction. It CANNOT do that if contaminated.
In a pinch, I use aerosol cans of Brake cleaner or MEK, then use a air nozzle from my air compressor, CLEAN AND DRY!!! But when building something, I have jars of solvents and do a final wash of all bolts, screws, nuts, in a first and second wash, then on a mesh screen and blow off with air,. Anything still not clean gets washed again. And lay out on paper towels for installation.
First wash off all hardware is in my solvent tank which has a little diesel in it, and rest is stoddard solvent, then washed with HOT HOT HOT water and air blow dry with compressed air. Then anything critical is washed again in lacquer thinner in the jars or MEK (Lacquer thinner is cheaper and less toxic, but MEK or Brake cleaner will evaporate off with NO residue)
Once cured, any part with loctite to my knowledge can be exposed to oil and lube to your hearts content (Such as a oil passage) and no issues.
Personally I would install the sludge trap plug (Cleaned of course and the crank threads as well) with a careful application of BLUE,, then once installed for extra security a few drops on the threads seam/joint with GREEN and allow to cure. (Green frees off with the torch method as well)
Do not slop large amounts of the LOCTITE on anything, MORE is NOT better, very small amounts are adequate.
See:
http://www.loctiteproducts.com/p/t_lkr_blue/directions/Loctite-Threadlocker-Blue-242.htmSee:
http://www.loctiteproducts.com/p/t_lkr_red/directions/Loctite-Threadlocker-Red-271.htmSee:
http://www.loctiteproducts.com/tds/T_LKR_GREEN_tds.pdfLoctite® Threadlocker Green 290™ is designed for the locking and sealing of threaded fasteners. Due
to it’s low viscosity and capillary action, the product wicks between engaged threads and eliminates the
need to disassemble prior to application. Loctite® Threadlocker Green 290™ cures when confined in
the absence of air between close fitting metal surfaces. It prevents loosening from shock and vibration
and leakage from shock and vibration and protects threads from rust and corrosion. The product can
also be used to fill porosity in welds, casting and powder metal parts. Localized heating and hand tools
are needed for disassembly.
For the record, I have never used LOCTITE Corp solvents or cleaners,,, I am sure they are good, but I do just fine using my methods.