Hydraulic Lift Bleeding down

mikemaddux · Sep 29, 2014

With a Bush Hog attached, It lifts fine when cold-warm but once hot it doesn't lift much at all (about 6". It will quickly drop when either the clutch is depressed or when I kill it (cold or warm).

I'm ordering the gasket set to take a look but was wondering if ya'll had any idea on which part(s) are most likely needed to correct the problem.

The tractor is at our place in East Texas about 2.5 hours away from me so I have to work on it on the weekends I can get away from the house.

I changed the fluid last weekend but it made no difference.

Bruce(VA) · Sep 29, 2014

" I'm ordering the gasket set to take a look but was wondering if ya'll had any idea on which part(s) are most likely needed to correct the problem."

Nope.

Not until you do some more checking.

See tip # 16 at the link.

Post back w/ what you find.
75 Tips

old · Sep 29, 2014

I will almost bet if you pulled the inspection plate off the one with the dip stick and had a look see you would see oil dripping form the lift cylinder. If that is so you need to replace the piston and seals with the improved NAA style of piston and ring set up and bet that would fix it

souNdguy · Sep 29, 2014

Dropping when clutched usually means big leak, 'usually' that leak is piston to cyl as old said. But as Bruce said, its not good to order parts before finding out what's broke!

howdy1960 · Sep 30, 2014

Like old and bruce said don't order parts till you know what needs fixing and like SG said 'usually' it's the piston leaking. Another problem area is the relief valve. However mine was not the piston nor the relief valve but rather a blown gasket on the pump which involves dropping the pump. One thing I did was to upgrade to newer style NAA piston and ring and also replaced relief valve since I was in there any ways. I spent under $100 to repair/upgrade. Is also a great time to really clean the sump of any junk.

showcrop · Sep 30, 2014

At the price of gas to drive 2.5 hours, I would say that it is a good plan to buy all possible parts. you can always return the unused ones if they hurt the budget.

Ken in MI · Oct 2, 2014

All good information here. If it were me, and I
had a 5 hour round trip to work on it I would
order the cylinder, NAA Piston, O ring and back up
washer, and a pressure relief. You already have
the gaskets. Even if it is the cylinder or piston,
i would change the pressure relief while you have
the oil drained and the top off. You will have
about $160 dollars into the fix. What will 2 trips
to the tractor cost? You should also get the cam
follower pin in case.

Tall T · Oct 2, 2014

Ken,

Would all of the parts you suggested he pick up be applicable and advisable for me when I decapitate my NAA hydraulics?

Thanks,
Terry

Ken in MI · Oct 3, 2014

Honestly know notta about a NAA. I do know the NAA
piston works with the 8N. I just finished that
rebuild on mine a couple weeks ago. It was leaking
down fast. Now it holds a disc at least
overnight... I looked through the inspection hole
and saw oil coming from above, but ordered and
changed the pressure relief "while I was in
there".

mikemaddux · Oct 3, 2014

(quoted from post at 15:16:06 10/02/14) All good information here. If it were me, and I
had a 5 hour round trip to work on it I would
order the cylinder, NAA Piston, O ring and back up
washer, and a pressure relief. You already have
the gaskets. Even if it is the cylinder or piston,
i would change the pressure relief while you have
the oil drained and the top off. You will have
about $160 dollars into the fix. What will 2 trips
to the tractor cost? You should also get the cam
follower pin in case.

That is exactly what I have done. The parts will be here next week. I figured that I'd go ahead and replace them while I was in there....they haven't been exposed to human eyes in over 30 years....besides, I know Bruce expects me to do the opposite of what he advises and I wouldn't want to disappoint him

Hydraulic Lift Bleeding down

mikemaddux

Member

Bruce(VA)

Member

old

Well-known Member

souNdguy

Well-known Member

howdy1960

Well-known Member

showcrop

Well-known Member

Ken in MI

Member

Tall T

Well-known Member

Ken in MI

Member

mikemaddux

Member

Similar threads