ym1602 brakes service and repair

[grumbolt]

ive checked the forums and havent found a diagram or anything regarding my tractors brakes setup..

everything i find shows a dry brake that you can access the shoes by removing the cover forward of the rear axles..
my tractor looks to have a wet brake system. the brake actuator goes into the rear axle housing with a boot, which is what leads me to believe it is a wet brake system.

that being said, my brakes tend to stick if i use them.. very aggressively stick, like i have to move the tractor forwards and backwards to break them loose to be able to move it.

if driving forward and you use the brakes, the left wheel will lock and slide even on pavement until you stop and rock back and forth a few times to free it up.

i cant find any diagrams that match my tractor setup. do any of you have any documentation or tips about how to resolve this it would be greatly appreciated.

currently i wont let anyone else in the family drive it because i want it to perform and act correct.

thanks in advance for the help!

 

[careyo63]

I've seen this before. BRB-1602 -1602,F16 Brake Rod Boot. Only two models use it is what I'm showing. Pretty much the same Braking Sys. as the 1601. Only 2 unusual no doubt. F16 manual etc. may have more info.?

 

[winston1]

I think you have a 1602 and yes it does have wet brakes. You can look thru this 1802 manual to see what yours looks like.

https://www.tractorforum.com/threads/yanmar-ym1802-ym2002-parts-manual-npc-1390.51715/

 

[careyo63]

Fredricks 1800,1802-4WD. 3Cyl. 20HP. the Prod. Yr. is different. YM1800-88 and up, YM1802-82,83. The Ym1802 might be the same?

 

[grumbolt]

awesome info, thanks guys!

 

[grumbolt]

i was incorrect before stating it went into the axle housing, it does indeed go to a housing just forward of the axle.. according to the diagrams it seems to be disk brakes. i wont know for sure what is wrong with it until i tear into it, but i suspect the fact the transmission had lots of water (several gallons) in it when i got it and no telling how long it had been there, the brake assembly probably needs to be completely disassembled, cleaned, lubricated, and properly reassembled and adjusted. anything short of that will most likely give unsatisfactory results... i am including a pic of what my housing looks like..

 

[grumbolt]

i guess the question is, what should i pay particular attention to when i disassemble this? lol
and its probably a stretch that any of you would have the service manual section dealing with servicing the brakes.

 

[bmaverick]

i guess the question is, what should i pay particular attention to when i disassemble this? lol
and its probably a stretch that any of you would have the service manual section dealing with servicing the brakes.

You can check out the YM 3-digit domestic service manuals on that site or the YTOG.

 

[grumbolt]

You can check out the YM 3-digit domestic service manuals on that site or the YTOG.

i started looking to see if any of them had the wet brake setup, no luck so far lol

i was trying to find out which domestic it most closely resembled be it john deere or yanmar etc..

i know i am overthinking it, i will end up just opening it up and playing it by ear.. good news is i can make my own gaskets. seems a shame to waste the hydraulic fluid i just put in there a month ago though lol.. i may drain it out and if it looks pristine filter it and reuse it, if not, just call it a trans case flush.. luckily for me i live near a rural king and they carry fluid pretty inexpensively compared to everywhere else..

 

[bmaverick]

i started looking to see if any of them had the wet brake setup, no luck so far lol

i was trying to find out which domestic it most closely resembled be it john deere or yanmar etc..

i know i am overthinking it, i will end up just opening it up and playing it by ear.. good news is i can make my own gaskets. seems a shame to waste the hydraulic fluid i just put in there a month ago though lol.. i may drain it out and if it looks pristine filter it and reuse it, if not, just call it a trans case flush.. luckily for me i live near a rural king and they carry fluid pretty inexpensively compared to everywhere else..

Meets J20C, then it's a good fluid. If it states 'compatible with', set the jug aside and move on.

Since 2020, I've not seen a good price on any of the fluids in a long time.

@rScotty might know what models have wet brakes. I've not updated the master database on this detail.

In the Gray Market models, the YMxx20 have wet brakes. Though, no service manuals for the grays.

 

[grumbolt]

Meets J20C, then it's a good fluid. If it states 'compatible with', set the jug aside and move on.

Since 2020, I've not seen a good price on any of the fluids in a long time.

@rScotty might know what models have wet brakes. I've not updated the master database on this detail.

In the Gray Market models, the YMxx20 have wet brakes. Though, no service manuals for the grays.

View attachment 4641060

View attachment 4641061

good to know about the "meets" vs "compatable with" difference..

rural kings version meets the requirements, and is around 45$ per 5 gallon bucket... https://www.ruralking.com/cam2-promax-tractor-hydraulic-j20-c-oil-5-gallon-565298

 

[winston1]

Taking pictures as you go can help. Here are a picture or two of a 1720 brakes. The o2 and 20 series have wet brakes.

 

[grumbolt]

Taking pictures as you go can help. Here are a picture or two of a 1720 brakes. The o2 and 20 series have wet brakes.

thanks very much for the pics, it removes lots of the mystery lol... i found this video over on youtube that explains the operation of the mechanical disk brakes.

looking at those pics, i suspect that the water in my hydraulic fluid may have caused corrosion at the pivot points that prevent them from releasing as they should..

 

[bmaverick]

good to know about the "meets" vs "compatable with" difference..

rural kings version meets the requirements, and is around 45$ per 5 gallon bucket... https://www.ruralking.com/cam2-promax-tractor-hydraulic-j20-c-oil-5-gallon-565298

When I lived down south in TN, the first time I had changed the fluid was the Rural King brand meeting J20C. Living up north, the nearest RK is 2hrs away.

The TN Rural King took over an old K-Mart at the west end of Clarksville. Great location and even a huge K-Mart building. The store is so big, they expanded it! I surely miss the place. RK is far better than the Blains Farm & Fleet up here and a huge leap over the TSC store offerings.

 

[rScotty]

@rScotty might know what models have wet brakes. I've not updated the master database on this detail.

In the Gray Market models, the YMxx20 have wet brakes. Though, no service manuals for the grays.

As far as I know, none of the vintage USA domestic Yanmars had wet brakes. Everything from about 1970 to 1990 - from the smallest tractor on up to the YM336D - they all had the infamous drum & friction shoe style dry brakes.

I don't know about the later imported Yanmars sold as JDs or Cub Cadets. Does anyone know if they had wet brakes?

Those pictures just posted of the wet brakes disassembled sure look like a better brake design, and look to be designed with serviceability in mind, too. I like 'em.

I agree with grumbolt, might as well get into them and see if cleaning things up will give a serviceable brake. New parts may not be necessary. Might take the back wheel off to give yourself some working room..... I'll be interested to hear what it looks like in there.

That gasket looks to be a tough one to make. I think instead of making a paper gasket I'd clean both surfaces, lightly grease or oil one side of the housing , and paint on a smooth thin layer of silicon gasket maker on the matching cover side. Then just let it sit an hour or so unti the silicon skins over and starts to cure - this is so the silicone doesn't ooze out. I test it with a finger....
Once it skins over, Immediately assemble and just lightly & evenly tighten the mounting bolts ....give it 24 hours and then tighten it on down.

I sure wish the dry brakes on my old JD tractor were as nice as those wet brakes..and as easy to work on.
Good Luck,
rScotty