720 axle seal leaking

[Danolw55 0]

I replaced what I thought was original axle seals with replacements from auto parts store. I believe hydraulic fluid is leaking out of axle seal below the bottom of the actual axle level when it is filled properly. Is there a special seal that needs to be used? The axle seems to be in good shape.

[Guest]

Can't help you unless you tell us the make & model of the tractor.

[JP 0]

Hi Dan, Welcome!! Did you replace the oring too? Did you take the brakes off to get to the seals? JP

[Guest]

I crossed the Victor number, 64050, over to a National number, 471733, and installed those. No leaks.

[D-17_Dave 12]

I just replaced those on my 620 and noticed the ones in it were a national # replacement from sometime in it's history w/ a single lip and the Simplicity orriginal replacements had a double seal lip on the axle. It appeared the the replacements were the right size but not correct for the application. To me this is very important. Also as JP mentioned, are the O-rings good? They need to be new and well lubed when they go back in so as to not get pinched and torn. Mike, I got interupted when I was wrighting this and I guese I should have read it after posting it.B) I guese I type like Ithink sometimes...Confused.

[Guest]

I don't understand the following statement: "Also just as im. are the O-ring seals as JP mentioned"

[JimS 1]

Dan, Sounds like you have a leak between the bearing support casting that holds the shaft seal and the transmission housing. An O-ring (Simp pt. no, 170839) is used to seal between these parts and it fits in a groove on the outside of the bearing cone. It may be missing or damaged, or the metal surfaces that the O-ring seals against may be damaged. That is why you have a leak even with the oil level being below the shaft. Looks like another tear down!!!