520H trans fluid overflowed

[DrabHorse 2]

I thought this was odd what happened yesterday.

First let me say I changed the oil and filter on the trans at the beginning of this summer and have been mowing with it all year and checking the fluid regularly, it was always good, never had to add any and was always right on the full line.

Well yesterday I stared the 520 just to move it out of the garage and around back and then I left it there all day. I was walking by and noticed oil was dripping off the axle and onto the inside of the tire like they do when the axles seals leak. But the oil was actually coming from up above by the dipstick, I pulled out the dipstick and the tube was full to the top with oil!?

Well later I drove it back into the garage and then today after it had been sitting all night I checked the trans again and the oil was at normal level on the stick. Wonder what happened?

[WH854 45]

I thought this was odd what happened yesterday

Well yesterday I stared the 520 just to move it out of the garage and around back and then I left it there all day.

[DrabHorse 2]

I thought it might have something to do with air, but I didn't think that would be likely to happen after using it all summer, somewhere around 40 hours run time.

[CRE1992 143]

I talked to the tech at my local dealer, and he had asked me if I had experienced the hydraulic oil regurgitation or throw up yet, and I said no.. He said it happens more often than people think, and it has to do with pressure still being in the pump, and when it releases it causes a surge because there is no where for it to go except for out the dipstick, because nothing is utilizing the pressure and relieving it. Such as lifting, or lowering a deck or moving.

Just some thoughts,

Charles

[kpinnc 16,181]

I've noticed a similar thing on my 520-H after it's been pushed. Something about the way the pump acts when the tractor gets rolled from one spot to the other. But, as you said the oil drains back into the sump in an hour or so.

Happens even more often if the tractor was switched off warm and them pushed a few feet shortly afterward.

[HorseFixer 2,013]

I too have that happen but on my 417A It had to be filled very slow for some reason a little at a time. I thought this odd cause my C-120 took the oil just fine. :banghead:

[buckrancher 2,695]

i was told by my local dealer to cycle the lift valve up down after you shut the tractor off this will release any pressure in the system

Brian