This is a serious safety issue. A stuck-open lower guard prevents it from covering the blade when you're not cutting, which is very dangerous. It's likely due to debris or damage.
First, disconnect the battery. Do not try to run the saw.
- Manually raise the lower guard using the retracting handle. Look inside for sawdust, wood pitch, or gum buildup around the hub.
- Clean it thoroughly. You may need to remove the blade to get proper access. Clean with a gum and pitch remover, hot water, or kerosene. Never use gasoline.
- After cleaning, release the handle and watch the guard closure. It should snap shut instantly and freely.
- Check that the retracting handle does not touch the tool housing.
If it's still sluggish or bent, the guard and spring are not operating properly. They must be serviced by a qualified repair person before any use. Do not clamp or tie the guard open.
Remember, before setting the saw down after a cut, always wait for the guard to close and the blade to stop completely.