Medium
1-2 hours
Gear Assembly 125433-9
OEM part for: Makita
Part Number: 125433-9
$92.56
In Stock
Ships within 1 business day 
Compatibility
This part will fit the following 4 machines
Makita
BDF451 Drill / Driver View Diagrams & Manuals
BDF451Z Cordless 1/2" Driver-Drill View Diagrams & Manuals
BDF451 (Type 2) Drill View Diagrams & Manuals
BDF451Z (Type 2) Drill View Diagrams & Manuals
This item works with the following types of products:
- Drill Parts
- Cordless Drill Parts
This part replaces obsolete part #: 125318-9
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Customer Repair Instructions ?
All our customer repair instructions are solicited directly from other customers just like you who have purchased and replaced this exact part.
Motor turned but shaft did not and had no torque. Essentially as if the clutch setting was at 1
Stan - January 15, 2018
Tool Type
Cordless Drill
Difficulty
Medium
Time
1-2 hours
Tools Used
Screwdriver, breaker bar
Parts Used
Removed chuck ( this was easier the second time around since it was recommended on this site that the culprit was originally the chuck... it wasn't}
Remove the 4 front bolts of the gear box.
Remove 2 screws from the rear motor brush housing
Remove all eight screws holding the handle housing together (8?)
Carefully lift the gear box up from the remaining housing and forward. This is can be sticky and a few light hammer taps can help. Be careful with the speed switch and keep both leaf springs on the sides. there are 2 cowl springs underneath the switch and one is attached to the gear box slide arm. Try not to disturb the motor armature anymore than necessary. The housing compartment has no tolerances on the fit.
Remove gear box forward and reverse installation paying careful attention to the speed button. Install gear box but do not screw on until handle housing is attached. Things will only go back together if the motor, brush housing and gear box are in their proper position and lined up properly in their handle compartments.
Attach side handle screws and chuck.
Remove the 4 front bolts of the gear box.
Remove 2 screws from the rear motor brush housing
Remove all eight screws holding the handle housing together (8?)
Carefully lift the gear box up from the remaining housing and forward. This is can be sticky and a few light hammer taps can help. Be careful with the speed switch and keep both leaf springs on the sides. there are 2 cowl springs underneath the switch and one is attached to the gear box slide arm. Try not to disturb the motor armature anymore than necessary. The housing compartment has no tolerances on the fit.
Remove gear box forward and reverse installation paying careful attention to the speed button. Install gear box but do not screw on until handle housing is attached. Things will only go back together if the motor, brush housing and gear box are in their proper position and lined up properly in their handle compartments.
Attach side handle screws and chuck.
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Our customer service team are at the ready daily to answer your part and product questions. We have a dedicated staff with decades of collective experience in helping customers just like you purchase parts to repair their products.
All our part reviews are solicited directly from other customers who have purchased this exact part. While we moderate these reviews for profanity, offensive language or personally identifiable information, these reviews are posted exactly as submitted and no alterations are made by our team.
All our customer repair instructions are solicited directly from other customers just like you who have purchased and replaced this exact part. While we moderate these reviews for profanity, offensive language or personally identifiable information, these reviews are posted exactly as submitted and no alterations are made by our team.
Based on data from past customer purchasing behaviors, these parts are most commonly purchased together along with the part you are viewing. These parts may be necessary or helpful to replace to complete your current repair.
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