Hydro Gasket
 

I am having a problem with the cork gasket that fits between the hydro pump and the rear end. The tractor is a 149. I have split the tractor five times trying to stop the Hytran leak.

My latest attempt included the addition of Ultra black gasket sealer applied to the cork. It leaks worse.

Has anyone had this problem? A leaking hydro gasket, despite every effort to fix it?

A few notes:
-It is definitely the gasket leaking. I can see the fluid trail.
-I am using brand new OEM gaskets purchased from Partstree
-I replaced this same gasket on my other 149, and it does not leak at all

I have replaced about 5 of these and NEVER had a problem.

I use or place a small film of gasket sealer on the opposite side of the "sticky backing" and whala......it's fixed.

I would suggest that looking at the "mating surfaces" to see if there is any gouges where the cork gasket mounts.

There are no obvious cracks or gouges on either mating surface. I have cleaned and prepared both mating surfaces with rubbing alcohol. I attach the sticky side of the gasket to the pump, then carefully slide it into place before bolting it back into position.

Like I said before, my other tractor does not leak at all after I replaced the gasket. This one is giving me fits.

I am thinking about putting two gaskets on it, back to back. Has anyone tried this?

I am also thinking about replacing the entire rear end. I don't know...

I know you said your sure it's the cork gasket but take a second look at the trunion shaft seals. Had one leaking on my 2182 and it looked like it was the cork gasket. Make sure every thing is spotless when you put it back together. Some pics of the pump and adapter that the pump bolts up to may show a problem.

Like Sam said, I would also look at the Input Shaft Seal and the Relief Valves. Where ever the leak is, is seems it is dripping down into the cork gasket area.

I actually replaced every seal on the pump last year. I am 100% sure the seals are good.

When the tractor was assembled, I stuffed some paper towel where the pump and the rear end meet. I let it sit. I did not start or run the machine. I checked it after two days, and the paper was soaked with hytran.

I took it apart again yesterday. Did the gasket replacement with ultra black. I decided to let it setup overnight. I checked it this AM. There was a puddle of Hytran on the floor. Upon inspection, the hytran in running from where the gasket meets the rear end.

When you take it apart are the gaskets torn? Do they look like they are compressing as the should? I'm just wondering if maybe Cub has a bad batch of gaskets, maybe they are too thin. It sounds like your doing it the way it should be done.

The gasket was torn this last time because it was stuck with the Ultra Black. Before that, no. The last gasket I removed was in good shape.

Here are some photos of the mating surfaces:

I don't see anything that should be preventing you from getting a good seal. That little nick is not the problem. I'd go get a small chunk of modeling clay, make a small ball about the size of a marble, put it on the tranny housing, then put the pump on and snug up the bolts. Then remove the pump and see what the compressed thickness of the clay is and compare it to the cork gasket. The gasket should be thicker.

Something you could try is Prusian Blue, I think Form A Gasket makes it. If the mating surfaces touch together with out a gasket, put a light coating on one surface and look to see if the surface you didn't coat is coated all around with no gaps. If any part of the surface doesn't have the Blue on it you may have found a problem of the surfaces not being flat.