Car getting hotter than usual
 

so not too long ago, i opened the cap to my radiator because my car would get hotter than usual, and when i took off the cap, it had was stuffed with some sort of sludge build up.i did a regular water flush and it ran good for a few months. The problem returned and theres some sort of sludge build up again under the cap. Also, the other day, after i parked, the water inside the container for the coolant was bubbling or boiling.I bought some flush for the radiator and block and a new bottle of coolant, does anyone know if this will solve my problem?

You maybe are experiencing a problem with air getting into the system.

I would do a complete flush, run with water, flush, run with water, flush, cycle that for a few times, then Fill with a 50/50 mix and fully bleed your system.

how do i bleed the system?

After you fill up the system, on the thermostat housing is a bleeder valve, you start the car, unscrew that valve with a towel around it and wait for a steady stream of fluid to come out.

Close. Shut off the car go for a drive. Shut it down, Start it up after a little bit and repeat once to make sure.