The reason why is due to thread expansion and contraction as those 4 studs/nuts threads expand and contract constantly during their heat and cool down cycles, thread locker will interfere with getting proper torque for holding down the cylinder and head properly and will result in air/fuel top and bottom gasket leakage resulting in lean running condition and eventually burn out your motor or cause it to not start, etc, etc, etc,
This adjustment must be done ONLY WHEN TOTALLY COLD, NEVER WHEN HOT OR WARM !!! or you will strip out the threads.
Those top nuts must be torqued down in an X pattern and hopefully your using a quarter inch drive torque wrench measuring in inch pounds to 144 inch pounds which is also 12 foot pounds if using a foot pound torque wrench...the 1/4 inch drive torque wrench can be found at Harbour Freight for about 20 bucks.
You will also need the proper size 1/4 drive socket to fit those nuts as well.
Amazing deals on this 1/4In Dr Click Type Torque Wrench at Harbor Freight. Quality tools & low prices.
www.harborfreight.com