Kubota B3030 Hydaulics non functional when cold

[flowerfarmer]

My mechanic changed the Hydro fluid. I put the tractor away and everything was working fine. Next time I started it up, FEL and 3ph wouldn't budge. I figured air in the system so I worked the steering for a few minutes and everything worked though more slowly than usual. After everything was thoroughly warmed up, all seemed normal. Then while using the loader, I heard a loud, high pitched squeel. I shut the machine down and checked everything out. The fluid level was high so I drained some out (about 1/2 to 1 pint), started her up, the squeel is gone and all is well until the next time I started it. Again, the hydraulics are dead until I work the steering and then slow 'til everything is warm. My mechanic hasn't a clue. There is a slight ringing sound (cavitation?) when the fel and 3ph are idle, it goes away while the system is worked. Thanks in advance for any of your ideas!

[Gordon Gould]

Just so we get the complete story to think about what did your mechanic use for hydraulic oil ?
How cold is it in Idaho now ?

[Ductape]

Just so we get the complete story to think about what did your mechanic use for hydraulic oil ?
How cold is it in Idaho now ?

My thoughts also. Did he use SUDT when he changed the hydraulic oil..... or oil off the shelf @ WalMart ?

[flowerfarmer]

Thanks for helping me tackle this problem. First thing I asked him was what kind of fluid he used. He told me he used AW32. I told him the machine requires multi-grade. Then he told me that it is a multi-grade fluid. He came out to look at the machine, felt the fluid and pronounced it not so viscous that it would cause this issue. Morning temperatures have been in the high 20s to low 30s F. Is he taking advantage of my ignorance?

[Gordon Gould]

The AW32 is most likely your problem. Your mechanic should have used the Kubota specified oil or it' s industrial equivalent. I would use general purpose AW32 in a wood splitter or log loader not a modern tractor. Especially one with an HST transmission, which I believe you have, and wet brakes and/or clutches. These components all require the specialized oils they were designed to use.

[moship]

I'm no oil expert, but agree with the above comment to change the fluid. I couldn't find anywhere that recommended this fluid for tractor use. In fact TractorSupply states the following about their Travelers AW32 fluid:
•This product is not recommended for transmission, differentials, wet brakes or final drive drive gears
•Perfect for log splitters, hydraulic lifts, etc.

[whitetiger]

Try to tighten your rubber suction hose clamps and filter on the right hand side . A crack or split hose is a fairly common problem with this series.
Find out the brand of oil he put in your tractor and see if it is a compatible fluid to Kubotas.

[Ductape]

I also say the oil is the problem. Drain and replace with Kubota SUDT.

[Jerry/MT]

Thanks for helping me tackle this problem. First thing I asked him was what kind of fluid he used. He told me he used AW32. I told him the machine requires multi-grade. Then he told me that it is a multi-grade fluid. He came out to look at the machine, felt the fluid and pronounced it not so viscous that it would cause this issue. Morning temperatures have been in the high 20s to low 30s F. Is he taking advantage of my ignorance?

Read your owners manaul about the fluid. AW32 is hydraulic fluid and I can almost bet that your tractor is spec'd for a transhydraulic oil that meets some Kubota spec.

AW32 is for hydraulic systems that do not have a rear axle running in the hydraulic reservior.

If I were you I'd find another mechanic or learn to change the fluids and filters yourself (these machines are not an F-22!) because this guy apparently knows nothing about tractors!

[flowerfarmer]

Thanks for all of your help. First thing I'll do is change the fluid and filters. What is the difference between UDT and SUDT?