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Finish Nailer Repair - Replacing the Driver Guide (Ridgid Part # 79004001022)
Article Breakdown
Finish Nailer Repair - Replacing the Driver Guide (Ridgid Part # 79004001022)
Tools & Materials
Grinder gears grinding? It's time to face the fix. Whether you are a master mechanic or a garage-based grinder, eReplacementParts.com provides the parts, procedures and facts you need to fearlessly fix what fails you.
The drive gear (also known as the pinion gear) attaches to the end of the armature. It transfers the direction of rotation from the armature to the spindle (and the grinding wheel). As with any gear, the drive gear will deteriorate over time. With hard use of the grinder, the gear can wear out much faster. Replacing the drive gear is easy to do.
This article provides step-by-step instructions for removing and installing the drive gear on a Makita grinder.
Let's get started. REMOVING THE DRIVE GEAR [top] 1. Remove the side handle.
Unscrew and remove the side handle from the grinder.
2. Remove the guard.
Loosen the lock-screw on the guard assembly.
Rotate the guard assembly to disengage it from the housing.
Remove the guard from the grinder.
3. Remove the gear housing.
Remove the (4) screws from the gear housing.
Separate the gear housing from the motor housing.
4. Remove the rear cover.
Remove the (1) screw from the rear cover.
Slide the rear cover away from the motor housing.
5. Disengage the motor brushes.
Use a pick to (gently) lift the brush spring from the back of the carbon motor brush.
Reposition the brush spring alongside the motor brush (against the brush holder).
Pull (gently) on the wire lead to disengage the motor brush from the armature.
Repeat this step to disengage the second motor brush.
6. Remove the armature assembly.
Slide the armature assembly (which is attached to the gear housing cover) out of the motor housing.
7. Remove the drive gear.
Grasp the armature to prevent it from rotating.
Use a wrench to remove the drive gear retaining nut.
Remove the drive gear from the armature spindle.
INSTALLING THE NEW DRIVE GEAR [top] 8. Install the drive gear.
Install the new drive gear onto the armature spindle.
Secure the new drive gear with the nut.
REASSEMBLING THE UNIT [top] 9. Reinstall the armature assembly into the motor housing.
Slide the armature assembly into the motor housing.
Align the gear housing cover with the motor housing.
10. Reinstall the gear housing.
Install the gear housing onto the grinder (aligning the mounting holes with the gear housing cover and the motor housing).
Secure the gear housing to the grinder with the (4) screws.
11. Re-engage the motor brushes.
Use a pick to (gently) lift the brush spring away from the brush holder.
Position the brush spring against the motor brush.
Repeat this step to engage the second motor brush.
12. Reinstall the rear cover.
Visually inspect the wires for potential pinch-points and adjust/tuck the wires as necessary.
Slide the rear cover onto the motor housing.
Secure the rear cover with the screw.
13. Reinstall the guard.
Install the guard assembly onto the grinder.
Rotate the guard assembly to engage the mounting plate.
Secure the guard with the (1) screw.
14. Reinstall the side handle.
Install the side handle onto the grinder.
Tighten the side handle until secure.
You can't place a value on a job well done, unless you did it yourself. (Which you did.) Now you can place that value back into your own pocket. (Or into your business.) Not only did you refine your grinder at a fraction of the cost of replacement; you have expanded your skills far beyond the daily grind.