Just a thought regarding the threaded fastenings with Locktite "tm" industrial products
applied to them.
Removing those fastenings for the consumer is, accoriding to the "Locktite Industrial" tech support
pro's, best accomplished with hi temp heat applied directly to the fastening to get it HOT before trying to break it loose. If you are working near gasoline or fuel vapors on a motor
you'll have to be careful or better yet remove the tank, lines, and carb and plug the intake
to the motor case.
This product is a specialized plastic and comes in various grades. In production they treat the fasteners with a chemical such as Clean'n'prime or #213484 that chemically treats
the fastener surface to bond better with the Locktite as it is screwed into the case. In the industrial
grades of Loctite such fastenings around the clutch shouldn't have grades above #242 or below
#222 to hold 20 ft/lbs of torque and keep it safe from vibration. The proper installation of these treated fastenings is to coat the first 4 thereads of the fastener before installation and then pulling it up to the torque s
There is no adequate way to use a solvent to disolve the hardened loctite before removal as only heat will do that. The Locktite is color coaded and any "red" colored thread locker will bond it tight enough that the fastening may break before it come loose. Colors such as "red"(hardest)
"blue"(medium hardness) and "green"(light hold) are available for the consumer market that aren't as strong as some of the industrial products. But the products for industrial applications are made where the aim is to build products that will stay together thru the warrenty period and servic life. These Industrial products are sold by numerical
specification. Those who work on these items are not really considered.
Locktite produces a product called "Chisel Paint Strip" that will clean this material the factory uses
off the fasteners. (use in a well ventelated area with eye protection) Once cleaned the "red"
Locktite can be used on the fasteners (again coating only the first 4 threads of the end of the
fastener). This will coat the other threads as the fastener is installed. A thread cutting tap the
same size as the bolt hole could be used to "chase" the threads to remove residue from previous installations and then cleaned with carb cleaner aerosol with the thin tube that often comes
taped to the side of such cans.
Inserting an old screw driver or allen wrench into the fastening and hitting it with a hammer
won't release the Loctite as it is designed to insulate against vibration and impact. The
heat will cause the Locktite to soften enough to get it out. If the aluminum is heated and then
the fastener the removal may be successful. This is where a MicroFlame Mini-Torch that uses butane and can reach 2500 degrees temp focusing a very small area will be helpful. (I've seen the butane refill cans at WalMart made by Ronson in both the hardware and tobacco departments and the refillable mini pencil torches are available at Harbor Freight often for less than a $1.50 when on sale)
The numbers I've posted are from "Locktite Industrial Division" products and won't be available at a local hardware stores or WalMart. The green, blue, & red consumer products will be found at public
This information came from Loctite Industral's tech services. The grades specified would apply to
string trimmers and small motors such as these HT's from China.