Makita 18 volt hammer drill is slipping and is not closing Plastic cover has no traction . Teeth are stuck in open... does anyone suggest a fix please ?

i would suggest that you just buy another new unit, fixing it would be a pain in the ___.

The large black part of the chuck should turn left and right to extend (close) and retract (open) the three chuck teeth that hold the bit in place. Turn the chuck to open it far enough to get your bit fully in the chuck then turn it closed to hold the bit in. When the teeth make contact turn the chuck a bit further to get it tight enough that the bit won't slip. When you get used to it, sometimes it's easier to hold the chuck lightly and turn it by lightly squeezing the trigger to turn the chuck with the drill motor.

on the BHP451 there are 2 screws on the back cover that need to be removed and then you can access the brushes and on the BTD 140 the same is true. The part number I see is 194427-5. If I have helped in answering your question would you please vote accordingly and thank you.

Bjarne, odds are the variable speed function of the trigger is failing. There are Makita repair centers that perform repair, and sell parts if you want to take it on as a DIY project. Before proceeding, I would make sure the warranty has expired. If it is still in warranty a Makita repair center should repair it for no charge.

Just buy a new Makita 18volt.

NO!

you would need to replace the switch, but before doing that check the brush length for excessive wear. you can go to Makitatools.com for a breakdown for this model.

its prob stuck between gears one and two try a little wd40 on the gear selector switch

open the chuck all the way, insde there may be a screw in the bottom it's lefthand thread turn it clockwise to remove, the chuck is also threaded, right hand thread. close the jaws on the short end of an allen wrench and strike the long end with a hammer to break it free

Buy a hitachi li-ion 18 volt ds18dl.
All parts are repairable & replacebable should they breakdown. Ie gearbox.
Gearbox parts are not available on makita , only whole gearboix which can be expensive.
Cheers
Laurie