Front axle pressurized?

[SPYDERLK]

If you open the cap when the fluid is hot ( air escapes ) and then
replace it again , the air pressure will not be above atmospheric
again . Don't open when cold or it sucks in air again

The seal of many lip type seals is energized by positive pressure. Negative pressure, suction, slips by easier. This is apt to re-equalize the cold pressure causing the hot pressure to again be positive.
larry

 

[Jerry/MT]

Checked the fluid level a couple days ago on my TC34DA and when I unscrewed the dipstick there was a definite sound of pressure being released. This is the first time I can remember this sound when the dipstick has been removed. The fluid level was up to the full mark but not beyond it, tractor parked in shed so not in direct sunlight. Tractor had not been used for over a week so I am at a loss for an explanation. Anyone else ever notice this on their 4WD New Hollands?

I can't believe there isn't a vent for the front axle to keep that from happening. Look in your owners manual or call your dealer's service department and find out where it's at so you can unclog it. Otherwise you're going to have some blown seals and oil leaks. I hope RickB weighs in on this as I believe he works on these machines for a dealership.

 

[Egon]

The seal of many lip type seals is energized by positive pressure

So, as the pressure builds the seal gets better?:thumbsup:

 

[RickB]

So, as the pressure builds the seal gets better?:thumbsup:

If the lip is oriented towards the pressure, it surely does. To a point, of course.

 

[RickB]

I can't believe there isn't a vent for the front axle to keep that from happening. Look in your owners manual or call your dealer's service department and find out where it's at so you can unclog it. Otherwise you're going to have some blown seals and oil leaks. I hope RickB weighs in on this as I believe he works on these machines for a dealership.

Ford and New Holland compact tractor MFD axles have never been vented from the factory. That's going back nearly 30 years. New Holland has authorized axle venting in some cases when seal failure and demanding customers have made it the easy way out. There has not been a campaign, program, or design change moving from non-vented to vented axles on an across-the-board basis. Other CUT manufacturers front axles are generally not vented, with some exceptions. Axle and swivel seals are designed to withstand normal pressure buildup due to atmospheric and operational conditions, given a supply of clean (no water) lubricating fluids within. Small amounts of water trapped in an axle will raise havoc with case pressures as the water evaporates and condenses. Overfilling axle housings also creates high pressures due to lesser air volume. Front axle oils are generally neglected even more than antifreeze. Change your front axxle oil as recommended.

 

[mjonesnh]

Front axle oils are generally neglected even more than antifreeze. Change your front axxle oil as recommended.



Front axle oil was changed in March. Less than 50 hours put on tractor since all fluids were changed. I have talked to some other owners of New Hollands in the area and they said they experienced this with their tractors occasionally. Have decided this is probably a normal occurrence and a non issue.

 

[Schwermetall]

Hmm, just checked the fluid in my 15 hour old JD and it definitely released pressure too.

 

[arrabil]

My solution.

 

[Jerry/MT]

Ford and New Holland compact tractor MFD axles have never been vented from the factory. That's going back nearly 30 years. New Holland has authorized axle venting in some cases when seal failure and demanding customers have made it the easy way out. There has not been a campaign, program, or design change moving from non-vented to vented axles on an across-the-board basis. Other CUT manufacturers front axles are generally not vented, with some exceptions. Axle and swivel seals are designed to withstand normal pressure buildup due to atmospheric and operational conditions, given a supply of clean (no water) lubricating fluids within. Small amounts of water trapped in an axle will raise havoc with case pressures as the water evaporates and condenses. Overfilling axle housings also creates high pressures due to lesser air volume. Front axle oils are generally neglected even more than antifreeze. Change your front axxle oil as recommended.

Rick is that only the subcompacts or are the bigger(TN, TL TD, etc) NH's also unvented?

 

[RickB]

Rick is that only the subcompacts or are the bigger(TN, TL TD, etc) NH's also unvented?

Carrera built and designed axles used in NH, CNH, and other makes are generally unvented. CNH's own axles (TN,TL,TD) are unvented. ZF axles found in older Fords and Deeres typically are vented. Dana Spicer axles used in CIH Magnums and NH Genesis I believe are unvented.