Does a corded ryobi hammer drill have a fuse?

SOURCE: hammer drills and rotary hammers comparison

Basically yes. Lower power units are usually titled as "hammer drills." Higher power units, usually labeled "rotary hammers," tend to be larger and provide bigger impact forces. But there are a few differences that are worth knowing: The rotary hammer usually have a chisel only feature, for light chiseling and masonry removal. Rotary hammers also have specially designed chucks that only accept bits specifically designed to fit their chuck. The special chuck on a rotary hammer helps hold the drill bit and prevents it from slipping during use.

SOURCE: Bosch 11247 Hammer drill works

Usually replacing the o-rings on the piston, striker and Impact bolt will solve any hammering issues. That is considering there is no damage to the mechanical parts in the hammer mechanism.

SOURCE: I have an AEG hammer drill that no longer hammers.

service manuals AEG SB2E-1001

SOURCE: my hammer drill won't hammer.

when was the last time serviced?? If not recently then you would need to replace the o rings and look for other sticking/worn parts. Give me the exact model number and I will try and find you a breakdown and a rebuild kit. They are not that bad if you are handy with tools and take your time. Let me know

SOURCE: hammer action power there but weak

Bosch makes a special grease that is actually a mulit-viscosity oil thats a gel at room temp. At high temp it becomes liquid oil that lubes the gearcase and when the tool has cooled off it reverts back to a gel for containment purposes. If you use any other type of grease on these tools it will appear as if it is losing power, when it is actually being "bogged" down by conventional grease. The proper grease is Bosch part# 1 615 430 001-000. Retail price should be around $20 for a 225ml tube.