How do I remove the metal case of my sewing machine so I can replace a belt?

Clean all the fluff and lint with a 1" paintbrush. Clean any gummy oil deposits with spirits. Apply one drop of sewing machine oil to every part that slides and every pivot that has a hole in the joint.

Not much on that machine

https://www.google.com/search?q=Homestyles+model+F08-702-H-01+sewing+machine

Around the bobbin case: Put one drop of oil around the metal/metal spool case and under the machine if access can be gained. The main bottom shaft will have two bush bearings requiring oil as well as may be the gears and excentric feed cams. Keep oil away from any belts whilst working under the machine.
Dec 13, 2023

Where to oil a sewing machine

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just adjust to needle in fix to strait in needle clamp hole it operate to needle strait to hole so needle do nt break but needle is best buy qualtity

Sears carries many manuals for Kenmore. That's probably the best place to check--unfortunately, they generally are not free.

The sewing machine could probably use a good cleaning and oiling. These old (but great!) mechanicals need 1-2 drops of fresh, good quality sewing machine oil (Tri-Flow Synthetic Oil works great!) every place that metal rubs against metal. NO oil on plastic, nylon, rubber, or belts!!! Simply open the machine's top, left side, and free arm cover (if not a free arm, you'll need to access the underneath of the machine). Gently hand rotate the handwheel toward you and apply a couple drops every place metal rubs metal. Don't forget the lever & dial mechanisms too. Probably, in your case, the bobbin winder mechanism (do NOT oil the rubber tire!). Then you can apply hot air from a handheld hairdryer into the mechanism to help free it up.

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It appears to be a mechanical machine. If so, use ONLY good quality sewing machine oil (not 3-in-1, cooking oil, or the old can from grandmother's sewing basket). It would help if you could remove the case to access the internal parts, but be care to not force/break the case trying to do that. (An oil bottle with a long narrow spout is very helpful for getting into difficult spots.) Slowly hand rotate the handwheel (always toward you) and while watching, apply 1-2 drops of oil every place that metal rubs metal. Do NOT oil belts, cams, or plastic parts. If you can, turn the dials, flip the levers and oil those parts as well. Don't forget the moving metal parts under the machine as well, ie bobbin mechanism, feed dogs, etc.

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On a treadle sewing machine usually there is no adjustment on the tightness of the belt so you have to shorten it. There will be a metal clip holding the belt together and you can remove and cut the belt shorter and then put it back together. Be very careful to not cut too much off. Probably be a good idea to trim it a very little at a time.

In case of adjusting sewing machine timing, there are twomain parts that you should follow.To adjust the hook needle timing on the rotary hook, first,remove the bobbin, bobbin carrier, and covers so you can see the movement ofthe hook. This may involve removing the needle plate for top loadingassemblies, or removing the hook cap from the front of the machine. Itoften requires the removal of the lower covers to reach the componentparts. Adjust as needed when doing sewing machine repair.Set the machine to a straight stitch at the defaultposition. Different models have different default positions including themost common far left and center positions. If no problems are perceivedin needle bar positioning, the default position will suffice. If thereare needle bar position issues, these need to be adjusted prior to adjustingthe timing. Follow proper sewing machine repair procedures.Rotate the hand wheel toward youuntil you see the needle reach its lowest position and begin its rise. Now lookfor the point of the hook as you continue rotating the hand wheel. Thepoint of the hook should strike inside the needle scarf above the needleby about 0.5mm. Sewing machine repair is vital for smooth operations.Check to see if the hook fails topick up the thread. Double check the needle bar positioning including thehook needle spacing. If these are appropriate and the point of the needlestill fails to pick up the loop thread, proceed to adjust the timing of thehook. Maintain regular sewing machine repair. Look for the lower drivemechanism. It may be a lower shaft with gears on either end. If this isthe case, look to the right end of the shaft for a gear with adjusting setscrews. Loosen and manually adjust the position of the hook. Tightly hold thehand wheel while turning the drive shaft to set the proper position. Retighten adjusting screws. Some models have timing beltsthat control the timing of the sewing machine. Look for a belt connectedon each with to drive gears. Look for work cogs on the belt. Inmost cases, you can reset the timing belt, without replacing it. If,however, the belt requires replacement you will need to do so. Loosen the drive mechanism on the right side to free the movement of the belt.Manually adjust the position of the hook to the needle and re-tighten set screws. This knowledge is vital for effective sewing machine repair.Once the timing has been reset,conduct thorough test sewing on the sewing machine to make sure everything isworking properly.Hope this will help you. Good Luck.

If you turn the handwheel, can you see a metal ring rotating around the outer edge of the bobbin case? If not rotating, broken gear or timing belt off.
If that ring is turning, remove the needle plate and bobbin case. As this ring now rotates, you will a finger on the ring that will pass behind the needle from right to left and it should catch the thread from the eye of the needle. If this finger, the "hook" passes above the eye, you have a timing problem.

Let me know.

If you're having the same problem we did, the attachment is installed too high on the bar. Move it down as far as possible and see if that solves the problem. If it doesn't, check to see whether the machine is belt-driven; did the belt break or slip off?

Most likely a good clean and oil would be helpful. Sometimes even the motor needs oil.

Wheel on right side that controls the needle up and down is very tight...

The bobbin case is most likely not adjusted properly. The bobbin case has a small piece of metal that can be loosened with a screwdriver. Once it is loose you need to move it to a point that won't allow the case to move. The bobbin case must only be moved to a point to stop the bobbin case from movement. If it is too tight it will cause the machine from sewing.