Biodegradeable Gear Oil

[natenkiki2004]

This might not be the best place/forum to post this but there's always nice people around and I've seen oils mentioned here before.

I have an old Montgomery Wards (Gilson) front-tine rototiller. I have about $120 into it (bought it for $40, the rest went into gaskets and parts) and I really enjoy it for the money. It's front-tine but it gets the ground perfectly tilled for planting and has cast-iron gear housing and many cast-iron parts as well as an old flathead Briggs. Anyway, when I got it, the gearbox leaked fluid, dripped quite a bit overnight. I was lucky enough to find someone online after researching that actually had an original seal kit for the whole gearbox. I cleaned out the whole gearbox and installed the new seals. Last summer it worked perfectly and was bone dry.

This year, I've started to pull it out for spring cleaning and noticed that one side of the gearbox looks "wet". No puddles but just a bit of seepage. It's very thick 90w-150 gear oil I believe. It's not leaking like it did before but this is concerning to me. I don't want the oil leaking or saturating some dirt in the garden. A little bit can contaminate a lot of dirt. So I'm wondering about some kind of veggie oil. I know typical vegetable oil is way too thin for that application but it's just an example. Does anyone know of a bio-based oil that biodegrades for gear boxes? I wouldn't mind if some of that leaked into the garden.

Realistically, the rototiller is only for personal use, i.e. a small garden so only a couple of hours a year at most. It's old and I'll be looking for a replacement/upgrade but I would like to get my money out of this machine. I'll use it this year after cleaning the gearbox the best I can but next year... I'm not sure. Any thoughts/ideas?

 

[reynoldston]

Fill it with Lubriplate 105 thick enough not to leak and thin enough to lube the gears. It comes in a tube sold in most auto parts stores.

 

[natenkiki2004]

Hmmm, that gets me thinking. I have an almost new tube of general purpose lithium grease, like the kind you use for bearings and whatnot. What if I cleaned the gearbox and smeared that on all the surfaces and put a blob in there, packing it in?

Really, I only need a solution that will "work", it doesn't have to be 100% proper, just good enough for a few hours of use every year for a couple of years. I would be happy with that

 

[KennyV]

General purpose lithium grease has No extreme pressure additives, don't use it for what you have in mind...
You need a grease with Molly.
Doesn't matter how long you are using it, without a high pressure add your gears & bearings can be damaged.

Lubriplate is a great grease... but I'd use their #3000 for a gear box...:smile:KennyV

 

[natenkiki2004]

Molybdenum? I went back to the Lubriplate site and they actually have lube for worm gears, which is kind of what this gearbox is.

Lubriplate

It's actually close to the weight the manual specifies, SAE 140.

 

[reynoldston]

Hmmm, that gets me thinking. I have an almost new tube of general purpose lithium grease, like the kind you use for bearings and whatnot. What if I cleaned the gearbox and smeared that on all the surfaces and put a blob in there, packing it in?

Really, I only need a solution that will "work", it doesn't have to be 100% proper, just good enough for a few hours of use every year for a couple of years. I would be happy with that

Not general purpose lithium grease but Lubirplate 105 its used in boat outboard motor gear cases. You want the grease to flow but not leak out the seals. Called Lubirplate 105 which can be found in auto parts stores also used for assembling engines, axles and transmissions.

 

[natenkiki2004]

Not general purpose lithium grease but Lubirplate 105 its used in boat outboard motor gear cases. You want the grease to flow but not leak out the seals. Called Lubirplate 105 which can be found in auto parts stores also used for assembling engines, axles and transmissions.

But, is it really good for heavy pressure, heat and wear? After reading, it seems like people use it for outboard gear cases because of it's water resistance. Other than that, people seem to use it for pistol slide rails and racing engine assembly. From what I understand, it's more for temporary assembly so engine parts don't get damaged waiting for fresh motor oil to lube & cool parts. I don't see much mention of it for use in gearboxes. I won't need something that is water-resistant.

 

[reynoldston]

But, is it really good for heavy pressure, heat and wear? After reading, it seems like people use it for outboard gear cases because of it's water resistance. Other than that, people seem to use it for pistol slide rails and racing engine assembly. From what I understand, it's more for temporary assembly so engine parts don't get damaged waiting for fresh motor oil to lube & cool parts. I don't see much mention of it for use in gearboxes. I won't need something that is water-resistant.

sounds good to me, just telling you what I would use and yes outboard motor gears have very high pressure, You said you had seal problems so maybe a heavy gear oil? It just seems to me you would want a grease that would flow which you would want on gears. I also know that John Deere makes a grease that flows but don't know the name of it? Or how about putting some grease fittings into the houseings and give it some pumps of grease before each use?? Anything to get some lube onto them gears.

 

[natenkiki2004]

I fully appreciate your input I'm sorry if the last post sounded argumentative or snippy, I didn't mean it.

Right now, I have 85w-140 Valvoline gear oil in there and it only seeped, it didn't leak. But, it will only get worse. So I'm either thinking a thick grease that won't leak or a veggie-oil that I just top-off. Grease would probably be better and cheaper in the long run.

I know inside the gearbox there's a worm gear with a brass one of these that's run off of the worm drive:
Amazon.com: Murray 51405MA Worm Gear: Patio, Lawn & Garden
Then, for the tine shaft, it runs on 2 tapered bearings. That's it, pretty simple system.

Seems like Lubriplate 105 is good, all the posts mentioning it on outboard forums also talk about gear oil leaking. Looks like manufacturers used Lubriplate 105 for direct drive and then gear oil for shifting gearboxes. Does it have molybdenum? I looked for the data sheet but couldn't find a working link.

*EDIT*
Oh, and would I pack a glob in or just coat the gear and pack the bearings leaving mostly air in the gearbox?

 

[reynoldston]

Can't be that big or expenstive of a job to install new seals or are the shafts shot?