Homelite trimmer, gas, string - y is the string wrapping itself around the head of the trimmer?

It is a dinosaur is trimmer history.

https://www.google.com/search?q=Homelite+ST80+string+trimmer

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Pull the head off by turning the inner hub counter clockwise while holding the outer head still. Once the inner head pops out, turn it over and look for the string rotation arrow. If you can't find the string winding directional arrow, start the trimmer and determine shaft rotation direction (generally counter clockwise) and wind the string in the same direction as the head rotates when installed.
Pull about 5 arm lengths of string out of a string spool and cut it off. Place the inner trimmer head on an object that will hold it while you pull the string to even lengths through the winding hole (the support brackets of a pickup truck tail gate work well for holding the inner head while doing this).
Begin wrapping the string double wraps in the proper direction, laying them evenly and closely to the previous wrap, working it back and forth as the string begins to build up. Avoid crossing the string over itself more than necessary, the string can weld itself together if the strands cross to awkwardly. Once the string is wound, hold the head with one hand and slide the string through the outer head holes, avoid letting the string come unwrapped.
Carefully place the inner head down into the outer header. Avoid letting the string get caught between the inner and outer head. Once the heads are together lock the inner head onto the outer head by turning it and locking the round knobs into the outer head slots.
You can trim the string or let the trimmer guard do it. If the string doesn't feed it is either wound the wrong way, tangled between the inner/outer head or welded to itself.

Hello Joseph,
This can be a little tricky, but it can be done. First check for obstructions around spindle where string comes out. Check for twine, grass, trimmer line or debris wrapped around bottom end keeping it from turning. If there is nothing there check to see if you can gently turn it by hand, to see if its seized. You may have to disassemble the bottom end of unit from the engine. If you disassemble bottom end you will be able to tell if the problem is in the bottom end or not. Some models have whats called a drive connector which is a metal piece that connects the pto shaft from engine to the shaft that goes to spindle end. Drive connector is number 31 in this diagram. If you post actual model and serial number from tag of unit I can post accurate pics to help. Let me know if you have more questions, good luck!

I’m happy to assist further over the phone at https://www.6ya.com/expert/layne_0fccff498c319c32

i would remove the trimmer head then cut the string off

The string head on these units is very poorly designed. There is hardly anything in the head to retain the line. I suggest removing the stock string head and going to Home Depot and getting a replacement Universal type head or one for the Ryobi or Homelite They are basically interchangeable. Check the length available on the shaft end (threaded part) after removing the head.Use a large wrench or pliars to hold the dust cap when you unscrew the head. If you feel the driveshaft turning, don't continue turning head or you will break the flex driveshaft.

would suggest that the cable that runs the head is broken or there is too much material wrapped around the head... remove the engine off the trimmer and check the cable that runs to the head....

If it only runs with choke on, then mixture is too lean or idle set to low.
Adjust mixture initially at 1.5 turns, then move in or out as needed for highest idle when warm.
Make sure no leaks or clogged filter when adjusting.

Hard to say with string feed, but are you sure you are not putting the spool in backwards?

You can wrap a rag around the threaded end of the string head shaft after removing the bump knob to hold in place while turning the upper part of the string head counterclockwise to remove. Then you can do the same to remove the metal shaft adapter nut above that, exposing the flex shaft in its entirety.

sounds like you wound the string in the wrong direction, or reassembled head wrong

undo the 2 screws on top of the carb. The bulb is part of a 2 piece cap undo that and it fall out.