M9000 front loader, manual transmission, started leaking hydraulic fluid from vent tube on top of transmission. I was moving hay bales, front and on 3 point when I noticed the severe leak. The fluid seems thinned out. I shut down and let machine cool off. I checked hydraulic level on level surface, engine off and cold. The dipstick indicated very full even after all the leakage. Started up machine and operated front loader and 3 point and fluid started coming from vent. I am going to drain hydraulic fluid level to proper level and see if that is problem. What other things might cause this? The machine has seen a lot of hours. There was no leaking like this until the other day and the hydraulics function as expected. Thank you in advance for any insight.
Hydraulic fluid out of transmission vent
- Thread starter bsamot69
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85Hokie
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As the fluid gets hot it will expand and become less viscous - BUT if it is overfilled, it will spew out when it gets hot and the pressure increases inside the case.
I would do as you mentioned - if the fluid is old, change all of it. If fairly new, drain a little off and continue to see if it becomes no longer "very full" - to me "very full would be inches UP the dipstick.
report back what you find
I would do as you mentioned - if the fluid is old, change all of it. If fairly new, drain a little off and continue to see if it becomes no longer "very full" - to me "very full would be inches UP the dipstick.
report back what you find
North Idaho Wolfman
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Sounds like you have water in the fluid!
Drain all the fluid, make sure you drain all the drain plugs (most models have 4 to 5 drain plugs), and replace the filters too!
Drain all the fluid, make sure you drain all the drain plugs (most models have 4 to 5 drain plugs), and replace the filters too!
If it is water, you will want to find out how the water is getting in. If it is an open station, check the boot around the shift lever for tears.
.....check the boot around the shift lever for tears.
I've never heard of a shifter boot crying!
I've never heard of a shifter boot crying!
Actually Wolfman, M9's (open station or cab) only have ONE gearbox drain plug..... It's located behind the frontmost plug (which is the bellhousing drain plug), centered in the gearcase. When you pull that plug, be prepared for a fluid gusher as all 14.5 gallons comes out of the drain plug. Myself, I use an aluminum truck fuel tank cut in thirds with one third (with the end) as the drain pan.
Pretty hard to get water in the gearbox if it's a cab or open station model because there are only a couple places it can get in.
The main gearshift boot, the filler plug between the lift arms or the large hard rubber plug that sits in front of the fill plug. That rubber plug needs to have a coat of 3 Bond applied to it and set into the opening in the gearcase and allowed to cure to seal it. It's a rather large opening and if the plug is missing, that is the most likely place for water to get in.
The shift boot is the second place and it can be torn but not readily visible. You need to carefully inspect the pleats to make sure they are not split. I had to replace mine on my open station M9 as it was basically shot.
Cab models shift with a linkage arrangement and the shift tower is under the cab floor and not readily accessible to rain water, wash water or you either.
Actually, the gearcase is vented to the atmosphere with a breather hose halfway up the topside of the gearcase so, unless the hose is blocked with something, it's highly unlikely you could build pressure in the gearbox at all. Both the vent hoses on my M's have some sort of metal wool in them to keep crud out.
I think NIW is correct, the fluid is contaminated with water. Easy to tell, just look at it on the dipstick. If it's milky, it's got water in it.
Pretty large vertical space between the 'full' mark on the dipstick (full is just below the pto stub) and coming out the breather which is on top of the transmission case, I'd say at least 4", maybe 6" Would be a couple gallons overfilled to get that high.
rbargeron
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Wonder if fuel is getting into it somehow, diluting the oil and eventually overflowing? Not quite sure where a gasket failure could do that on your model. Is your machine ever fueled by someone who could mistake the trans filler plug for a place to put fuel in? I know, pretty crazy. But its possible.
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My report on m 9000 vent leak. Drained old fluid, installed 2 new filters and refilled with new fluid to proper level. Started tractor, backed up, operated 3 point and front loader. Fluid coming out of vent immediately. Tractor running less than 5 minutes. Where do I go from here?
I guess there are air-bubbles in the oil.
If there is a smal leak on the suction side of the oilpump(s), you get bubbles or foam in the oil. This increases the oil volume very quick up to 115% or more. The bubbles sometimes stay in the oil fore one day or longer.
If the suction side is restricted a little bit can also create bubbles because of a kind of vacuum.
Maybe you operate the tractor again until oil comes out of the vent and the drain some oil through an remotevalve outlet. Check for bubbles.
If there is a smal leak on the suction side of the oilpump(s), you get bubbles or foam in the oil. This increases the oil volume very quick up to 115% or more. The bubbles sometimes stay in the oil fore one day or longer.
If the suction side is restricted a little bit can also create bubbles because of a kind of vacuum.
Maybe you operate the tractor again until oil comes out of the vent and the drain some oil through an remotevalve outlet. Check for bubbles.
rbargeron
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Is that where its coming out? Try connecting a longer hose to it so the oil flows into a jug or something where you can inspect it for air bubbles. Also, see what kind of pressure is pushing it out. can you stop it with a finger? Maybe try running with the rear fill plug removed - does oil still come out the hose, or fill port?
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Sounds to me that possibly the hydraulic pump is sucking air and foaming the oil in the gearcase to the point of overflowing. M9's have a 2 section pump with a manifold on the bottom that feeds them with gearcase oil but the return to the gearcase (on an M9) with a loader is through a return to sump (gearcase) hose that enters through the PTO housing on the backend of the tractor Wondering (outloud) if the manifold or the connecting hose is leaking air and foaming the fluid as that is the only place where air can get into the system.. Per chance is the FEL jerky in movement or the hydrostat steering? You obviously have an entrained air issue but there isn't that many places for air to get into the fluid.
You are using Kubota fluid I presume?
You are using Kubota fluid I presume?
There was a video on YouTube of a guy who had a m of some size with fluid leaking like you describe.... I can’t find it at the moment....
I occasionally have oil blow out the vent on my m7060, not sure why, I take it as free (well, expensive) undercoating. Usually happens using an implement or when on Unlevel ground. (Only an inch or 2 out seems to make it difficult to get a good read on the puny dipstick, then a 1/2 gallon overfills it.....)
Watching with curiosity, hope it’s nothing serious
I occasionally have oil blow out the vent on my m7060, not sure why, I take it as free (well, expensive) undercoating. Usually happens using an implement or when on Unlevel ground. (Only an inch or 2 out seems to make it difficult to get a good read on the puny dipstick, then a 1/2 gallon overfills it.....)
Watching with curiosity, hope it’s nothing serious
The m9000 hydraulic fluid vent leak. The fluid is definitely full of bubbles, near foaming. I started tractor, operated front loader and 3 point. They work normal. Backed up and pulled forward, fluid started coming out vent. Definitely lots of tiny bubbles. All the things you have mentioned, suction side of pump etc, these are internal or external? Am I looking at some kind of teardown or is this verifiable and repairable without extensive disassembly? I'm ready for either.
If it just started after an oil/filter change, my bet would be leaking at one or both filters. Maybe old gasket stuck or new gasket wrinkled. I have heard of cracking the filter adapter if the filter is overtorqued.
North Idaho Wolfman
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The fix should be external, normally a hose.
There are 10 different variants to the M9000, a serial number or an exact model and I can give you some direction on what hoses and where to check.
There are 10 different variants to the M9000, a serial number or an exact model and I can give you some direction on what hoses and where to check.
On the M9's the suction and delivery are all external. I bet you have a loose hose fitting. Not uncommon for a tractor of that vintage.
I have 2 of the variants HDCC3 and the HDC and both of mine share the same exact suction and delivery hose / manifold arrangement. He has the FEL (like I do on both) and the fluid return line taps into the backside of the rear pto cover on both of them and I suspect his does as well. Looking at the WSM they all appear to be similar. The pump manifold (it's a 2 stage pump) is connected to the gearbox with a hose. I'm wondering if that hose is cracked or the clamps have come loose. I would think it would be on the suction side of the pump, not the delivery side and it's all external.
A model number would certainly be helpful at this point.