Rake John Deere 640 Hay Rake Gear Box Maintenance?

[wjb-49]

Hi everyone!

I have a John Deere 640 Hay Rake that operates fine, but I have a question regarding maintenance.

We have greased all fittings but do not know how to check the gear box lubricant. How do we check if the level is correct and what type of lubricant is used? Also, if we take the access plate off the gear box housing, would the seals have to be replaced?

As always, thanks for your help.

 

[Ridersupfarm]

WJB, has anyone replied to your question. I have the same issue with my 640. There does not appear to be a fill plug for the gear case. It would lead me to believe one has to remove the gear case cover to add grease, in which case how do you know how much to pack it with?

 

[Dederanch]

There is a small plate on the end of the gearbox where some service could be performed but the unit should be taken apart for full service.

I am rebuilding my new 640 purchase and the gearbox failed due to a lack of service.

The unit is packed with a low grade,wax base grease that just collected moisture and all the bearings failed.

 

[Ridersupfarm]

There is a small plate on the end of the gearbox where some service could be performed but the unit should be taken apart for full service.

I am rebuilding my new 640 purchase and the gearbox failed due to a lack of service.

The unit is packed with a low grade,wax base grease that just collected moisture and all the bearings failed.

Thanks. Yes, the gearbox has a service opening that is sealed with what looks like a freeze out plug. I've been reluctant to remove it since I don't know the availability of replacement plugs. I guess I'd better look into it so I don't repeat your unfortunate experience.

Regards,
Don

 

[Ridersupfarm]

The gearbox has a service opening that is sealed with what looks like a freeze out plug. I've been reluctant to remove it since I don't know the availability of replacement plugs. I'm just going to measure it up and find a compatible plug for that opening. Some models actually had a removable and reusable plug. I'm not that lucky. In any case it's a good idea to check the gear case for any water that could have leaked in and to top off the grease.

 

[Dederanch]

On my unit there is a small,round plate that is held on with 4 small bolts.

The plug that you are referring to is an insert plug that is the back side of the axle drive bearing.

I am convinced as I work through my project that the unit is not designed to hold oil or any liquid lube and requires grease and the lubrication is not "flung" as the gears turn and so the dirt or wear is held in the grease.

 

[Ridersupfarm]

On my unit there is a small,round plate that is held on with 4 small bolts.

The plug that you are referring to is an insert plug that is the back side of the axle drive bearing.

I am convinced as I work through my project that the unit is not designed to hold oil or any liquid lube and requires grease and the lubrication is not "flung" as the gears turn and so the dirt or wear is held in the grease.

My gearbox has only the "freeze out" plug. Others have responded that the lube is a heavy grease and not gear oil, probably why these units never seam to leak oil. Thanks for the response.

 

[wjb-49]

Sorry to be so late in thanking all of you for your replies. My rake has a plate held in place by bolts, so it's time to check if the grease is good. Thanks much!

 

[Ridersupfarm]

Update: Last year I had to replace the gear box bearing. Upon removal of the front cover, water dripped from the gearbox. The engage/disengage selector is not sealed well and water must seep down the selector shaft into the gearbox. While apart I drilled and tapped an inspection port in the gearbox and sealed it with a pipe threaded plug and a rubber gasket for future addition of lube.

 

[wjb-49]

Update: Last year I had to replace the gear box bearing. Upon removal of the front cover, water dripped from the gearbox. The engage/disengage selector is not sealed well and water must seep down the selector shaft into the gearbox. While apart I drilled and tapped an inspection port in the gearbox and sealed it with a pipe threaded plug and a rubber gasket for future addition of lube.

Thanks for sharing your experience with another good ol' JD 640 hay rake.