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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
Gears grinding on your nerves? 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 spindle gear attaches to the spindle on your grinder. It mates to the drive gear on the end of the armature. Its job is to transfer the direction of rotation from the armature to the spindle.
Like any gear, the spindle gear will eventually wear out. Symptoms of a worn-out spindle gear include lack of rotation at the spindle, loss of performance, or unusual "grinding" noises coming from the gear housing. With hard use of the grinder, the spindle gear will wear out much more quickly.
This article provides step-by-step instructions for removing and installing the spindle gear on a Makita grinder.
Let's get started. REMOVING THE SPINDLE 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 bearing box from the gear housing.
Remove the (4) screws from the bearing box.
Separate the bearing box from the gear housing.
5. Remove the upper spindle bearing.
Position the bearing separator around the rear bearing.
Tighten the bearing separator bolts.
Place the bearing separator (and spindle assembly) on the vise. The jaws of the vise should be opened wide enough to accommodate the spindle assembly (without touching it).
Use a punch and a hammer to tap the end of the spindle shaft until the bearing breaks free from the spindle.
Remove the upper spindle bearing from the assembly.
6. Remove the spindle gear.
Use retaining-ring pliers to remove the retaining ring from the spindle shaft.
Remove the wave washer from the spindle shaft.
Slide the spindle gear away from the spindle shaft.
Remove the spindle key from the spindle shaft. (The key is very small, and may fall out of the spindle shaft on its own when the gear is removed.)
INSTALLING THE NEW SPINDLE GEAR [top] 7. Install the spindle gear.
Install the spindle key into the spindle shaft. (The rounded portion should face the spindle).
Partially install the new spindle gear onto the shaft.
Align the keyway (on the spindle gear) with the key (on the shaft) and slide the gear the rest of the way onto the shaft.
Install the wave washer onto the spindle shaft.
Secure the spindle gear with the retaining-ring.
REASSEMBLING THE UNIT [top] 8. Reinstall the upper spindle bearing.
Slide the upper spindle bearing onto the spindle shaft.
Locate a socket that has the same diameter as the inner race of the bearing.
Position the socket squarely against the bearing.
Tap the socket with a hammer to press the bearing on the spindle shaft.
Continue tapping the socket until the bearing is fully seated on the spindle.
9. Reinstall the bearing box onto the gear housing.
Install the bearing box onto the new gear housing.
Secure the bearing box with the (4) screws.
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. 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.
12. 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.