1320 hydraulic problems

[outlawed]

just bought a clean little 1320 with loader that has a hydraulic problem that someone might be able to help me with. I know nothing about tractors but I am very mechanically inclined.

the hydraulics start howling and maybe grinding after 10 or 15 minutes of use, I suspect after the fluid gets warm. I hear noise at times from the diverter block and at times a different noise that sounds its coming from the hydro pump. the 3 pt was bleeding down so I checked the lift cyl and found a bad ring/seal so I replaced that , knowing it was not my problem but hoping maybe that the bad seal was robbing the system of the needed pressure. I have checked the manifold diverter valve and pressure relief which appeared ok. fluid and filter are nice and clean. I do notice when you curl the bucket or extend the hydraulics and max them out, the engine bogs as if its going to kill the motor. that does not seem right to me. I do have a pressure gauge I can hook up but I was unsure how to do this and not dead head the pump. the manual says to hook to the diverter block but the loader is tapped into that. the only open plug there is a return port and I didn't figure that would show the psi.

where would you guys start? remove injector pump and check that or does it sound more like a pressure relief problem?

 

[thebean]

Outlawed,

Lets set a couple things straight here.

First, Injector pump usually refers to fuel injection high pressure pump, not hydraulic supply pump. Regardless, don't start by pulling the hydraulic pump. Or the injector pump for that matter :/

Secondly, howling and grinding are different but neither is good in a hydraulic system. It means serious cavitation which will destroy eventually whatever part it is occurring in. This is typically caused by lots of water in the hydraulic fluid, or by air getting sucked in through a leak on the suction side of the pump (large tube coming from filter on rh side of under your feet to the pump on the front side of the engine. Figuring out where that is coming from is important.

Third, whenever a hydraulic ram is run all the way out or all the way in, you are effectively deadheading the hydraulic system. As pressure rises rapidly, a pressure relief valve either in the FEL control spools or the main PRV on the dist block will vent flow past the dead head to avoid damaging the pump by over pressurization. The engine rpm will dip a bit under a deadhead like this but not a lot. should not kill it at an idle. If it does or sounds excessive, your pressure relief on your distribution block is set too high.

No matter what you should stick that pressure gauge in the supply line somewhere and see what your pressures are at deadhead condition. Probably easiest for you, just detach one of the quick disconnects going to the FEL. Then take the fitting off the FEL flex hose side (male) and put it on your pressure gauge. Insert pressure gauge back into quick disconnect and watch pressure as you pressurize that line. It should be about 2400 psi I think.

Is this machine hydrostatic (hst) or manual? If hydrostatic, make sure your whining/howling sound is not related to your trans. As these transmissions wear they tend to blow by once the oil heats up and if you are lugging the hydro they will whine pretty bad. Either way your howling sound is related to viscosity. possibly blow by which would occur more with hotter thinner oil.