tc45 hyd leak

steve stiller · May 18, 2010

bought tractor in jan and first time i mowed pulled back in garage and found puddle of hydro oil on floor next morning. looks to be coming out on top of tranny under your feet and running down sides of tranny behind bell housing. I tighten all the hydro lines and even drilled with hole saw down through center/between feet to get to a banjo bolt in center and it was tight. any suggestions without ripping off whole body. thanks steve

jinman · May 19, 2010

Steve, sorry about the leak, but I think you may be chasing a ghost. What I mean by that is that your symptoms are identical to what I noticed when my power steering reservoir was leaking. The engine fan causes the oil to blow backwards and it shows up on the bell housing behind the engine and can be seen also behind the fuel filter and engine oil filter area. On your tractor, the transmission is way back under the seat, and a leak would show up on the bottom of the tractor but not anywhere on the engine bell housing. On the left side of the engine, you have the HST filter assy and plumbing up to the HST cooler, but any leaks in that area should be easy to find by cleaning the tractor and then watching for oil to appear.

Of course, I could certainly be wrong, but from your description, it sounds to me like something other than your transmission, probably the power steering reservoir hoses from a hose clamp. Good luck, and let us know what you find.

steve stiller · May 19, 2010

i'll check tomorrow, wouldn't be the first ghost i have chased!

steve stiller · May 20, 2010

well its not the power steering, **** hyd fluid down to add. its right under where your left foot would be and behind the bellhousing. Its tuff to look at but if you look under front of rear fender it looks as its leaking around a tube/fitting.

jinman · May 21, 2010

Well RATS! I was hoping it would be an easy one. I've attached a photo of the HST hydraulic flow diagram. The fitting you are talking about is the flow from the HST cooler as it enters the HST transmission.

In this illustration, the large yellow line at the top is the suction feed to the HST charge pump (a small pump on the front of the transmission that supplies pressurized fluid to the transmission). The charge pump output (pink line) goes to the HST cooler. From the cooler (blue line) the fluid goes to the HST filter and then into the top of the HST. It actually flows through a seal in the mounting flange of the HST. Finally, after being used by the HST, fluid flows out the top yellow line and returns to the reservoir.

I'm not sure whether your leaking line is the top (blue) line or the return (yellow), but the blue line can be running at 200 psi or greater as input pressure to the HST. The yellow line should be very low pressure.

steve stiller · May 21, 2010

looks to be #9 in photo and i don't need to tell you it looks to be a pita to get to. looks as you have to remove body to get to it. used it tonight with checking fluid and its dumping bad on the belly mower. don't see it spraying, but it is leaking down the side.

Carykong · May 21, 2010

Steve, How many hrs on your tractor?

jinman · May 22, 2010

steve stiller said:
looks to be #9 in photo and i don't need to tell you it looks to be a pita to get to.

You are right Steve, it is a bit of a pita, but it can be made simpler by removing your rubber operator station mat and opening the access panel right under the hump. I'm including a picture that shows the panel removed on my tractor. I'm also including a picture that shows the area where you are working.

There's also a panel below the seat that allows access. I had to lift my platform to work on my HST pedals when they broke and that's when I took these photos.

To get the rubber mat off, I had to cut a small slot in it so it would come out from around the joystick hydraulic lines. It's a small cut and is hidden by the joystick cowling, so it won't even show. Once you get the mat off, you will have access to the fitting. That's also the location of the pressure test points for the HST transmission. Those have been reported to be a problem and leak sometimes. You might get lucky and find it is one of them instead of the banjo fitting.

NWOH_Grizz · May 23, 2010

My T2310 (TC40) had a hydraulic leak when it was delivered in January, and it came from a line on the left side of the transmission. It was directly right of the brake pedal shaft, its the junction of a horizontal metal line that turns up to vertical, and another metal horizontal line that turns down to vertical, and they are joined by a short piece of rubber hose with a hose clamp on either end. Both hose clamps were finger loose. Tightened them up, leak gone. Just another place to look.