This article is designed as a guide to provide some basic assistance when you need to fill or replace your machine gearbox oil. We are using the G1021Z as an example, but this applies to many of our Grizzly planers. Your manual demonstrates the main way to drain and fill the oil in the gearbox. We want to stress this procedure does work very well. However, we often have customers question if there is an easier way to perform this task. We have provided the instructional below because it requires less specialized equipment to get the oil properly changed. In the manual, it calls for a very long tube and funnel or requires the use of a pump to get the oil up under the head casting and fill the gearbox normally. This method is an alternate and sometimes easier way to fill the oil for your machine.
Items you will need to get started:
1 quart 80-90 weight gear oil
A catch pan for the old oil
A small tipped funnel
Gloves & Safety Glasses
Old Rags (preferably ones you have used or do not care to use in the shop)
Hand tools (wrenches, hex key, &/or allen wrenches)
- Disconnect the machine from power. We recommend putting your gloves during this step if desired. We also recommend safety glasses.
- Use the catch, collection pan, or bucket to hold the drained oil from the gearbox – set it under the gearbox.
- Remove the drain plug with the correct wrench from the bottom back corner of the gearbox.
- Remove the fill plug with the correct wrench from right under the main head casting on the front side of the gearbox. This will allow the oil to drain a little faster.
- Remove the dust hood and the top cover of the planer.
- Locate the four normal size cap screws that hold the gearbox to the main head casting.
Remove one of the gearbox cap screws and fill the gearbox from the cap screw that was removed using a funnel just until the oils starts coming out of the drain plug.
Wait for the oil to completely stop coming out of the drain plug – while waiting you can clean the plugs and apply new Teflon tape.
Re-insert the drain plug that has Teflon tape on it to seal the gearbox again – do not install the fill plug yet.
Using a small tipped funnel from the top of the machine where we removed the gearbox back left cap screw, start slowly adding the 80 – 90 weight gear oil in through that hole. Add a little bit at a time until you see the first sign of oil at the fill plug coming out.
Stop the pouring of the oil.
Wipe off any spilled oil on top of machine. Re-install the cap screw holding the gearbox to the main casting.
Reinstall the cover and the dust hood.
Wipe down the side of the gearbox around the fill plug hole.
Make sure the fill plug is cleaned and Teflon has been wrapped on it.
Install the fill plug.