Opinions please on this brake mod for YM2310 tractor?

   / Opinions please on this brake mod for YM2310 tractor? #1  

etpm

Veteran Member
Joined
Jun 30, 2021
Messages
1,544
Location
Whidbey Island, WA
Tractor
yanmar ym2310
Hi Folks,
The brakes in my YM2310 keep sticking. The left side especially. So today I decided to tackle the problem. When I bought the tractor it came with 4 new shoes in a box which means the tractor is getting new brake shoes at least. A big part of the problem is the actuating shaft rusting in the cast iron plate. After hours of work today I got the rusted shaft out. The shaft has an undercut area that is obviously a grease reservoir. The problem though is that this reservoir can only be filled by taking the brakes apart. A thankless task for an old guy with bad arthritis in both wrists and back.
So I'm thinking about adding a zerk so I can grease the shaft. But I don't want any grease to get into the area where all the braking is done. I do want the brakes to work after all. To keep the grease from getting inside the brake housing I'm thinking about filing a small groove in either the shaft or the bore. This groove would only lead to the outside. It would be pretty easy to file a small groove in the shaft from the undercut to the outside. When greasing all I would need to do is watch for grease coming out of the area where the actuating shaft exits the brake plate. The shaft is a very close fit in the bore so I think even a small groove will allow grease to flow out rather than in. Keeping the grease reservoir full of grease will keep any water from getting past the reservoir and into the brake housing.
Opinions? I have a box full of zerks and several round and triangular files just waiting to be used. Lotsa grease too.
Thanks,
Eric
 
   / Opinions please on this brake mod for YM2310 tractor? #2  
Hi Folks,
The brakes in my YM2310 keep sticking. The left side especially. So today I decided to tackle the problem. When I bought the tractor it came with 4 new shoes in a box which means the tractor is getting new brake shoes at least. A big part of the problem is the actuating shaft rusting in the cast iron plate. After hours of work today I got the rusted shaft out. The shaft has an undercut area that is obviously a grease reservoir. The problem though is that this reservoir can only be filled by taking the brakes apart. A thankless task for an old guy with bad arthritis in both wrists and back.
So I'm thinking about adding a zerk so I can grease the shaft. But I don't want any grease to get into the area where all the braking is done. I do want the brakes to work after all. To keep the grease from getting inside the brake housing I'm thinking about filing a small groove in either the shaft or the bore. This groove would only lead to the outside. It would be pretty easy to file a small groove in the shaft from the undercut to the outside. When greasing all I would need to do is watch for grease coming out of the area where the actuating shaft exits the brake plate. The shaft is a very close fit in the bore so I think even a small groove will allow grease to flow out rather than in. Keeping the grease reservoir full of grease will keep any water from getting past the reservoir and into the brake housing.
Opinions? I have a box full of zerks and several round and triangular files just waiting to be used. Lotsa grease too.
Thanks,
Eric
I've had to free up similar stuck brakes on three Yanmars, where I suspect the cover has never been off since they were new 40+ years ago. Whatever Yanmar did, it lasted a long time before sticking.

I think if you simply clean everything thoroughly, rub a thin coat of grease on the shaft, and replace the o-rings at both ends of the shaft, then it would be more than a decade before one sticks.

Seems to me it's impossible, or at least pointless, to try to improve on Yanmar's designs or maintenance procedures.
 
   / Opinions please on this brake mod for YM2310 tractor? #3  
Yanmar brakes have had a long history of rusting. It's an oddity in something that was designed to be used in a wet environment and is so well designed otherwise.

BTW, that brake cover sure can be difficult to remove if it has gotten rusty. A real wrestling job. Take the rear wheel off to get room to work. And congratulations on getting yours apart. I know instances where people have had to cut the cover up to get the cover and shoes to let go of a rusty brake drum - which is bolted to the transmission shaft.

But In fact, several areas on on the older Yanmars were known to have moisture problems: The fuel cap, the steering wheel-to-steering box water water path, the steering column drain, the shifter levers on top of the tunnel, and of course the brakes. These were all areas that Yanmar knew about and mentioned in their updated shop notes. Also the key switch. All can be improved with simple modifications.

From working on the USA Yanmars, I know generally what most of the manual brake systems look like. The O ring and cavity idea Yanmar used to keep water from migrating past the shaft will actually work half way well if yours is one that was originally assembled properly with a compatible grease. Too many of them were not pre=greased at all, and others used a grease that destroyed the O ring. That system only works if it doesn't start to rust.

So one solution is just to go with the original if you can. The O rings you find are probably going to be aftermarket and that is OK, but check the material type to to make sure the O ring material is compatible with the grease you use. A good water-resistant grease should stay there a long while.

If you also want to improve the system we can do several things along with your idea for a zerk.
Look and measure to see if there is gap on the shaft where it protrudes to the inside of the brake cover, with enough room - a quarter inch or so - you can add a floating seal - called a "backup O ring seal" on the inside before you assemble the shaft. A backup O ring seal looks like a washer but is made of Buna N rubber. Available in almost every size from McMaster Carr for not much money. Inexpensive. (from McMaster Carr in pkg of 100 or simply make them yourself from a sheet of Buna N).

Sometimes I would mill enough off the inside of the shaft protrusion in the brake cover to fit such a seal. Sometimes the cover already had enough space to stack up stacked several backup shaft seals. Filling any space - or making space - to put back up seals in there allowed their own elasticity to seal against water or grease intrusion along the shaft.

If you can do that to keep the grease out of the workings, no reason in the world why it wouldn't be even farther improved by some judicious filing on the shaft to make the groove you describe and adding a greasable zerk.

There are a few other things, too. The brake cover was originally fastened to the transmission casting with six studs and nuts plus an amazing thin paper gasket, but Yanmar abandoned the gasket in a shop note update in favor of silicone seal. Apply silicone with your finger and let it skin over - about 30 minutes - before assembling. Permatex "Form a Gasket" or any of the exhaust RTVs will work. Any extra bead that extrudes inside won't matter.

And finally, Yanmar's venting for the brake plate was inadequate for high humidity. They didn't ever figure that one out - or else ignored it.
What happened was the high heat from braking in wet air followed by cooling would cause condensation inside the brake housing ....but the brake cavity was so well sealed that the condensation had not enough ventilation to dry out. On my own Yanmar I tapped a convenient place on the brake shoe backing plate and then screwed in in a brass plumbing fitting with a couple of inches of copper tubing pointing down..... Giving the condensation a path to exit. Two such vents would have been better - top and bottom both.

There, with those changes the brakes should last much longer. Yanmar offered rivited friction pads for the shoes. I prefer their molded type shoes with the interlock molded as part of the friction surface. Some of the brake drums came pre-rust pitted. If you have that, lathe it smooth or replace the brake drum.

BTW, Yanmar's factory fix for the "water in the steering box" problem was to send dealers a box of thick mylar Yanmar DECALs with instructions to glue them onto the center of the steering wheel to keep water from accumulating in the depression there. So if you see an old Yanmar with a decal right where you would expect a horn to be, that is why.

For the problem of rainwater leaking past the fuelcap/fuel gauge they provided a $20 fuel cap rebuild kit along with a warning to assemble the sealing O ring carefully and without any grease.....

For the rainwater seeping past the rubber boots on the shifting tunnel - a problem with all tractors that still exists today - get in the habit of tarping the tractor when it is left sitting outside.

The drain hole at the bottom of the steering wheel column accumulates dirt - Yanmar knew that - and pointed out in a shop bulletin that the drain hole can be cleaned out with a wire....

Very simple fixes.
Luck,
rScotty
 
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   / Opinions please on this brake mod for YM2310 tractor? #4  
@rScotty That is an amazing list of fixes and improvement ideas! Thanks for sharing it.

All the best,

Peter
 
   / Opinions please on this brake mod for YM2310 tractor?
  • Thread Starter
#5  
I've had to free up similar stuck brakes on three Yanmars, where I suspect the cover has never been off since they were new 40+ years ago. Whatever Yanmar did, it lasted a long time before sticking.

I think if you simply clean everything thoroughly, rub a thin coat of grease on the shaft, and replace the o-rings at both ends of the shaft, then it would be more than a decade before one sticks.

Seems to me it's impossible, or at least pointless, to try to improve on Yanmar's designs or maintenance procedures.

Yanmar brakes have had a long history of rusting. It's an oddity in something that was designed to be used in a wet environment and is so well designed otherwise.

BTW, that brake cover sure can be difficult to remove if it has gotten rusty. A real wrestling job. Take the rear wheel off to get room to work. And congratulations on getting yours apart. I know instances where people have had to cut the cover up to get the cover and shoes to let go of a rusty brake drum - which is bolted to the transmission shaft.

But In fact, several areas on on the older Yanmars were known to have moisture problems: The fuel cap, the steering wheel-to-steering box water water path, the steering column drain, the shifter levers on top of the tunnel, and of course the brakes. These were all areas that Yanmar knew about and mentioned in their updated shop notes. Also the key switch. All can be improved with simple modifications.

From working on the USA Yanmars, I know generally what most of the manual brake systems look like. The O ring and cavity idea Yanmar used to keep water from migrating past the shaft will actually work half way well if yours is one that was originally assembled properly with a compatible grease. Too many of them were not pre=greased at all, and others used a grease that destroyed the O ring. That system only works if it doesn't start to rust.

So one solution is just to go with the original if you can. The O rings you find are probably going to be aftermarket and that is OK, but check the material type to to make sure the O ring material is compatible with the grease you use. A good water-resistant grease should stay there a long while.

If you also want to improve the system we can do several things along with your idea for a zerk.
Look and measure to see if there is gap on the shaft where it protrudes to the inside of the brake cover, with enough room - a quarter inch or so - you can add a floating seal - called a "backup O ring seal" on the inside before you assemble the shaft. A backup O ring seal looks like a washer but is made of Buna N rubber. Available in almost every size from McMaster Carr for not much money. Inexpensive. (from McMaster Carr in pkg of 100 or simply make them yourself from a sheet of Buna N).

Sometimes I would mill enough off the inside of the shaft protrusion in the brake cover to fit such a seal. Sometimes the cover already had enough space to stack up stacked several backup shaft seals. Filling any space - or making space - to put back up seals in there allowed their own elasticity to seal against water or grease intrusion along the shaft.

If you can do that to keep the grease out of the workings, no reason in the world why it wouldn't be even farther improved by some judicious filing on the shaft to make the groove you describe and adding a greasable zerk.

There are a few other things, too. The brake cover was originally fastened to the transmission casting with six studs and nuts plus an amazing thin paper gasket, but Yanmar abandoned the gasket in a shop note update in favor of silicone seal. Apply silicone with your finger and let it skin over - about 30 minutes - before assembling. Permatex "Form a Gasket" or any of the exhaust RTVs will work. Any extra bead that extrudes inside won't matter.

And finally, Yanmar's venting for the brake plate was inadequate for high humidity. They didn't ever figure that one out - or else ignored it.
What happened was the high heat from braking in wet air followed by cooling would cause condensation inside the brake housing ....but the brake cavity was so well sealed that the condensation had not enough ventilation to dry out. On my own Yanmar I tapped a convenient place on the brake shoe backing plate and then screwed in in a brass plumbing fitting with a couple of inches of copper tubing pointing down..... Giving the condensation a path to exit. Two such vents would have been better - top and bottom both.

There, with those changes the brakes should last much longer. Yanmar offered rivited friction pads for the shoes. I prefer their molded type shoes with the interlock molded as part of the friction surface. Some of the brake drums came pre-rust pitted. If you have that, lathe it smooth or replace the brake drum.

BTW, Yanmar's factory fix for the "water in the steering box" problem was to send dealers a box of thick mylar Yanmar DECALs with instructions to glue them onto the center of the steering wheel to keep water from accumulating in the depression there. So if you see an old Yanmar with a decal right where you would expect a horn to be, that is why.

For the problem of rainwater leaking past the fuelcap/fuel gauge they provided a $20 fuel cap rebuild kit along with a warning to assemble the sealing O ring carefully and without any grease.....

For the rainwater seeping past the rubber boots on the shifting tunnel - a problem with all tractors that still exists today - get in the habit of tarping the tractor when it is left sitting outside.

The drain hole at the bottom of the steering wheel column accumulates dirt - Yanmar knew that - and pointed out in a shop bulletin that the drain hole can be cleaned out with a wire....

Very simple fixes.
Luck,
rScotty
Thanks for the great reply. Your post and the post preceeding mention o-rings. I saw no o-rings nor were there any grooves for an o-ring. I'll look again to see. The lack of o-rings and the machined in undercut in the shaft which is obviously for holding grease is what made me think of adding the zerk. If I do find an o-ring then I will evaluate adding a zerk.
Thanks,
Eric
 
   / Opinions please on this brake mod for YM2310 tractor? #6  
Thanks for the great reply. Your post and the post preceeding mention o-rings. I saw no o-rings nor were there any grooves for an o-ring. I'll look again to see. The lack of o-rings and the machined in undercut in the shaft which is obviously for holding grease is what made me think of adding the zerk. If I do find an o-ring then I will evaluate adding a zerk.
Thanks,
Eric
I've seen several variations on that brake backing plate. It's been years, but some did exactly the same job and were probably interchangeable. All OEM. One type was cast aluminum in two versions - one with ribs and one without. The other was pressed steel for the main plate with functional pieces welded on - including the shaft support - which was clearly made by welding a bushing to the brake backing plate.
As you say, evaluate by function. You stand as good a chance of improving it as they did.

Those running changes tell me that Yanmar was aware of and trying to fix the problem. If you look at their parts books they have a philosophy of making changes by serial number during a model run. Interestingly, so does JD. And Yanmar was very open about deliberately trying to emulate some of JD manufacturing and sales methods back when they first came to the USA.

BTW, the member "California" is well known on this forum for his long time with Yanmars and his clever use of innovative repairs. Just so you know.... "Pointless" indeed..... :--)
rScotty
 
   / Opinions please on this brake mod for YM2310 tractor? #7  
Well there you have it, the difference between the comments of an owner-maintainer of an orphan model (that was designed to be owner-maintained). Versus the real tractor mechanic and pro machinist / engineer with decades of broad experience on these. With access to the factory bulletins, even.

rScotty you need to answer more of the technical questions, because you have the breadth of experience we individual owners will never accumulate, because anything breaking on a Yanmar is rare! Anyhow, your in-depth posts are greatly appreciated.
 
   / Opinions please on this brake mod for YM2310 tractor?
  • Thread Starter
#8  
Well there you have it, the difference between the comments of an owner-maintainer of an orphan model (that was designed to be owner-maintained). Versus the real tractor mechanic and pro machinist / engineer with decades of broad experience on these. With access to the factory bulletins, even.

rScotty you need to answer more of the technical questions, because you have the breadth of experience we individual owners will never accumulate, because anything breaking on a Yanmar is rare! Anyhow, your in-depth posts are greatly appreciated.
Greetings California,
BTW, I was born and raised in the Bay area. I left when I was 21. I could hardly wait to get out of the pit. That's besides the point though. That's because the point is that the shaft I was considering filing a groove in does indeed have an o-ring groove. I did not see it or the o-ring until I wire brushed the corrosion away. So, since there is an o-ring I went to the local o-ring purveyor and bought me a couple. So that I will have one when I do the brake on the right side of the tractor. I am still considering adding a vent to the brakes. But maybe, living in the PNW about 30 miles north of Seattle, grease and the new o-ring might just be enough. It's not like I will be using my tractor like the picture I saw of a Yanmar tractor similar to my 2310 being driven through a rice paddy in water so deep that the guy driving the tractor had his feet submerged. Just another day at work driving the tractor half submerged. The guy looked bored too. Driving in water that deep must be a common experience for rice growers.
Eric
 
   / Opinions please on this brake mod for YM2310 tractor? #10  
I believe it's more condensation than just rain water. Mine stayed inside and would end up with moisture in the brake housing,
I always used anti seize on the shaft
 
 
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