Unfortunately this rifle is not worth repairing. In Excellent condition it is worth $18. It has an FPS of 250 FPS. That's slower than a Daisy Red Ryder. I really suggest you purchase a new air rifle. These air guns were not designed to be repaired.
Marksman is owned by Beeman. If you want to try I suggest you call Marksman at 800-822-8005
Any rifle with a version two or version three gearbox. That includes the AR-15 series of guns (M4s, M16s, and anything of the like) or MP5s. These gearbox versions are the easiest to fix and upgrade.
It depends on the model and what is wrong with it.
Do not attempt to "fix" ammunition. Dispose of it properly. Ask your local police for help.
It all depends on what is wrong with it.
Take it to a gunmsith.
See the link below.
You need the services of a good gunsmith
I would have it looked at by a compitent gunsmith.
Leave this to a gunsmith
I hate to answer a question with a question but, can you be more specific?
You take it to a qualified gunsmith.
You mean Air rifle? See the link below