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Hi, My Makita demolition hammer will turn on and the motor will run, but no hammering. I have changed the brushes and it’s still the same outcome. I was thinking of buying a new one, but I thought I’d try my hand at repairing it. I hope you guys can help me out thanks.

According to the Makita Hammer Drill HM0870CQ instruction manual (available online in pdf), when the brushes are changed, the grease should also be changed. This seems to be a common feature with demolition hammers. Also, if the tool was stored in a cold area, it may have to be run for five or more minutes to warm up the grease enough for the tool to hammer. If the tool ran , there was probably nothing wrong with the brushes; the grease was either cold or depleted. Do an internet search of . This will probably tell you all you need to know.

Hi @jaimodoode , I’ve never worked on an impact drill but here’s the technical information manual for the drill which shows how to disassemble and assemble it. You may want to check the operation of the impact bolt as this is what creates the hammer action. Here’s a link that in general explains how the impact system works. Hopefully between the two of them you will be able to figure it out