L3650 trans fluid

[aemsee]

Bought this 3650 recently. Have been accumulating fluids and filters. Could not see through sight glass, so ordered one of those as well. Thought the glass was clouded over.
Nope. That wasn't it. The fluid is milky..and WAY over full. Hopefully changing out filters and fluid will remedy the intermittently reluctant glide shift shuttle valve.
I would like to flush it out, but not at the price of the UDT fluid. Thoughts on refilling it with cheaper fluid just to flush it, before filling with the UDT? I do not see any sparklies in it.

 

[Joisey]

Could be short operating times in cold/cool weather making moisture accumulate and never get hot enough to evaporate the water.

 

[Russell King]

If I am not mistaken that is still “mostly“ a gear driven tractor. If you wanted to flush it you could use some cheaper fluid like Traveler UTTF which is equivalent to UDT (but not UDT2 or SUDT2).

But if you just replace the fluid then the new fluid will dilute any contaminated fluid and using the tractor harder will evaporate off the water. If using SUDT2 then that will hold the water in suspension well.

I assume you are at least covering the tractor if you leave it outside for storage. If not, that could be where the water is coming from split leaking seals on top of the trans case.

 

[North Idaho Wolfman]

So I take it you have a GST.
Elaborate more on the reluctant shifting.
FYI: I can tell you just about every square inch of the inside of the transmision and GST control on thhat unit. I had to go through mine quite a few times when i got it to get it fixed up properly.

 

[aemsee]

So I take it you have a GST.
Elaborate more on the reluctant shifting.
FYI: I can tell you just about every square inch of the inside of the transmision and GST control on thhat unit. I had to go through mine quite a few times when i got it to get it fixed up properly.

sometimes shifting between forward and reverse I need to move the lever a couple of times before it starts to move. That is really the only thing I have noticed

 

[aemsee]

If I am not mistaken that is still “mostly“ a gear driven tractor. If you wanted to flush it you could use some cheaper fluid like Traveler UTTF which is equivalent to UDT (but not UDT2 or SUDT2).

But if you just replace the fluid then the new fluid will dilute any contaminated fluid and using the tractor harder will evaporate off the water. If using SUDT2 then that will hold the water in suspension well.

I assume you are at least covering the tractor if you leave it outside for storage. If not, that could be where the water is coming from split leaking seals on top of the trans case.

I have only had it a few weeks, but pretty sure it had been stored outside before I bought it. It will eventually have a home in my barn

 

[North Idaho Wolfman]

Does it hesitate when you shift gears.

 

[aemsee]

Does it hesitate when you shift gears.

at times it does hesitate

 

[North Idaho Wolfman]

A little is normal on gear change as it's not a perfect system.
but on shuttle it should be within a second or so to engage.

You next step would be to check input pressure.

Do you have the WSM (aka Service Manual)?

 

[aemsee]

A little is normal on gear change as it's not a perfect system.
but on shuttle it should be within a second or so to engage.

You next step would be to check input pressure.

Do you have the WSM (aka Service Manual)?

Yup. Have shop manual, owners manual for tractor, owners manual for engine and just got the parts manual. I am a bit OCD. I'll do the fluid/ filter change next couple of days. See how it reacts with fresh juice. TY

 

[North Idaho Wolfman]

The parts manual is Ok for pictures but a lot of the part numbers have changed.
For current part numbers use this:

Kubota Tractor Corporation - Illustrated Parts List

- K-PAD - Parts Lists - Illustrated Parts Lists - diagrams

apps.kubotausa.com

 

[oregontrail]

Interesting yours was "WAY over-full." I just added fluid to my L3450 GST and the little gauge window showed no change, so I kept on adding. I realized too late that the yellow part was probably milky fluid sitting on top of darker fluid. I'm new to this tractor so I don't know what to expect. I plan to flush and change the hydraulic fluid but I'm waiting until I have attached a new loader to it and run it a bit, in case the loader hoses have contaminants in them. Is there any problem with running it over-full for a while?

BTW, the glass looks dirty but it's on the inside.

 

[North Idaho Wolfman]

Interesting yours was "WAY over-full." I just added fluid to my L3450 GST and the little gauge window showed no change, so I kept on adding. I realized too late that the yellow part was probably milky fluid sitting on top of darker fluid. I'm new to this tractor so I don't know what to expect. I plan to flush and change the hydraulic fluid but I'm waiting until I have attached a new loader to it and run it a bit, in case the loader hoses have contaminants in them. Is there any problem with running it over-full for a while?

BTW, the glass looks dirty but it's on the inside.

Being a GST don't run it too long with contaminated fuild in it or you will be in for an expensive repair.
Water or air entrained fluid fill damage the clutch seals.

 

[oregontrail]

Thanks for the warning, @North Idaho Wolfman. Given that it's hard to see the fluid level in the little round window, I'm not confident about the fluid level. When I remove the cap on the transmission (between the operator's feet) and look in, I see metal that's wet with oil but not covered with fluid; in other words, the gears seem to be sitting in a shallow bath. Is that what it's supposed to look like? If I understand right, the entire hydraulic system has just one continuous reservoir with two filling points (the other being behind the seat), but I would imagine that the 3-point hitch and FEL would both require a source of fluid that has some reasonable volume.

 

[Russell King]

A lot of people recommend using a dye in the fluid to be able to see it. You may also want to change the sight glass just so it is as clear as possible (but the dye will probably make it easy to see anyway).

If you have a John Deere dealer around they probably have red dye on the shelf like this

John Deere Hydraulic Oil Dye - MT3668

www.greenpartstore.com

There are other brands and colors but none are orange (as far as I know).

 

[oregontrail]

Oh what a great idea, thanks @Russell King. I'm ordering it.

 

[North Idaho Wolfman]

Thanks for the warning, @North Idaho Wolfman. Given that it's hard to see the fluid level in the little round window, I'm not confident about the fluid level. When I remove the cap on the transmission (between the operator's feet) and look in, I see metal that's wet with oil but not covered with fluid; in other words, the gears seem to be sitting in a shallow bath. Is that what it's supposed to look like? If I understand right, the entire hydraulic system has just one continuous reservoir with two filling points (the other being behind the seat), but I would imagine that the 3-point hitch and FEL would both require a source of fluid that has some reasonable volume.

Yes that's normal not to see the fluid looking in the fill port.
You would be surprised how little of fluid is taken by those 2 systems, they just move fluid from one side to the other.
The front and rear fill points both go to the same location.

Get a new sight glass they are cheap and easy to install.
Also if your still having issues adding dye to the fluid makes it much easier to see.

Sight glass:

 

[oregontrail]

Thanks for the advice! Looks like you can just pry out the old one and push in the new (I had assumed that the sight glass was a permanent, immovable part of the case).