Mustang 2040 Hydraulic Fluid Level

[crmotoxr]

1997 Mustang 2040: In a very short period of use my hydraulic reservoir fluid level goes way up. After about 5-10 minutes using the machine the level will go from normal cold level, to over half up the fill tube/dip stick. The fill tube and dip stick are about two feet in length. The oil does not feel hot at all. The machine seems to operate ok during this period. Any idea? Thanks.

 

[Tazza]

Sounds like it is cavetating. Have you replaced your hydraulic filter(s)? and are there any oil leaks that may be drawing in air?

 

[crmotoxr]

Sounds like it is cavetating. Have you replaced your hydraulic filter(s)? and are there any oil leaks that may be drawing in air?

I have replace the oil (ISO 46AW) and the filters several times. I also noticed the lift cylinders where leaking around the dust seal. Air entering the system is my thought too. Those cylinders are now rebuilt and I will test them this weekend. The only other thought right now is the suction line from the tank to the gear pump and or the pump it self.

 

[crmotoxr]

I have replace the oil (ISO 46AW) and the filters several times. I also noticed the lift cylinders where leaking around the dust seal. Air entering the system is my thought too. Those cylinders are now rebuilt and I will test them this weekend. The only other thought right now is the suction line from the tank to the gear pump and or the pump it self.

Saturday: Got the cylinders rebuilt and installed. Cycled them several times all the way up and down to bleed any air. Replaced filters again. All seems to operate good. Sunday: In 5-10 minutes, running 1/2 to full throttle, the fluid level went up about 3/8" to 1/2" from normal cold level. However, before running the machine I noticed the hydraulic fluid level was solid on the dip stick. After running the machine 5-10 min I noticed the fluid had some very, very small looking bubbles. Fluid temp gauge hardly registered anything. I do know it is normal for the hydraulic tank to have pressure in it. Any other ideas would be of great help. THanks.

 

[Tazza]

Saturday: Got the cylinders rebuilt and installed. Cycled them several times all the way up and down to bleed any air. Replaced filters again. All seems to operate good. Sunday: In 5-10 minutes, running 1/2 to full throttle, the fluid level went up about 3/8" to 1/2" from normal cold level. However, before running the machine I noticed the hydraulic fluid level was solid on the dip stick. After running the machine 5-10 min I noticed the fluid had some very, very small looking bubbles. Fluid temp gauge hardly registered anything. I do know it is normal for the hydraulic tank to have pressure in it. Any other ideas would be of great help. THanks.

The oil tank should be vented...
Give it a few days of operation, see if the bubbles disappear. If you drag in air with replacing cylinder seals, it will take time to get it all out.

 

[Des]

The oil tank should be vented...
Give it a few days of operation, see if the bubbles disappear. If you drag in air with replacing cylinder seals, it will take time to get it all out.

Tazza the mustangs run a pressurised hyd tank.I would be checking the hose clamps on the suction hose that runs from hyd tank to the gear pump.

 

[Tazza]

Tazza the mustangs run a pressurised hyd tank.I would be checking the hose clamps on the suction hose that runs from hyd tank to the gear pump.

Thanks for that Des, i never knew that. See if i remember that for next time

 

[crmotoxr]

Thanks for that Des, i never knew that. See if i remember that for next time

Thanks for all the advise! Replacing the suction line and clamps is going to be my next step.