x590 Hydro screwed the pooch

[Stupid]

Oil blowing out the transaxle case on the passenger side. To the AD next week I never abused the tranny. Never pulled accessories with the machine. This unit has a filler/ expansion tank. I noticed that some oil is carried out of the tank in vapor as the internal volume expands. This creates a film on the top of the tank that eventually builds up and solidifies around the perimeter of the cap where it meets the top of the tank (I cut in dusty conditions). Well the build up was going up the cap about an eight of an inch and was like concrete. I think the unit couldn't vent and over-pressure blew out something on the case side.....we shall see. To this end I suggest cleaning the area on top of the expansion tank regularly. Now for a question. Should the cap be screwed down tightly or screwed down and left loose. I see no other way to vent if not left loose. As we know there is a foam filter in the tank neck under the cap.

 

[WDF1988]

Go ahead and screw the cap down tight. It vents via the notch in the top of the cap and down the side of the threaded neck. (See red circles in pic) Some vapor and dust sticking to it would be considered normal. If yours is abnormal, please reply with some pictures. The tanks are known to leak where they meet the metal transmission housing. Usually with a new o-ring and some finesse, you can get it to stop. A few, I've had to replace the tank. The pic is from a new X590 on our showroom floor. Good luck!

 

[Stupid]

Great reply, thanks. I'll inspect mine and take a pic if different.

 

[Stupid]

No valve in this cap. The roof is completely smooth on the inside. No oil from the expansion tank connection to the trans body that I can see. It all appears to be on the side by these two lines. I cleaned off and let it sit, shatted up again with oily dirt on the entire lower half of the trans. Is this the wrong cap?

 

[WDF1988]

That is some major leakage. Your cap appears to be an earlier style, but I dont think it's causing the issue. My advice is to power wash off the transmission really good and then put the tractor up on jackstands and let it run and look for the leak. Make sure your oil level isn't low. I'm guessing you have either the input shaft seal leaking on the top or something. The areas it can leak from are the input shaft seal on top under the fan, on the side where those two hydraulic lines connect, axle seals, and of course the plastic tank we discussed previously. The oil looks too high to be leaking where the bottom cover bolts to the main housing. Also check the black filter cap on the front of the transmission. With the amount of oil on that transmission, it shouldn't be hard to pin point the leak after you give it a good bath.

 

[Stupid]

^Thank You