Komatsu wa320-3mc transmission issues

[FSFarm]

Hello, I have a komatsu wa320-3mc that appears to slip out of gear, it will drive on flat ground fine but it will not go up a incline or with the bucket producing any sort of friction also there is a cavitation noise that comes from the pump at any rpm above idle, what should I do for diagnosing the problem? Thanks

 

[Simon C]

Have the hydraulic filters, and suction screens been cleaned or changed? Is the hydraulic tank full of oil. Is the pilot filter clean.?
How many hours on the unit.
Has the pilot pressure been checked.
Does the engine drop in RPM when going up an incline?
Need to start somewhere.
Simon C

 

[FSFarm]

We have changed two filters, a spin on filter up underneath the machine and a cartridge filter in the top of the tank. Its full of oil. Our next step was to locate and clean the suction screen. There is no change in the engine. Also part of the time its like the brake locks up. It acts the same through all gears. Reverse is better than forward. Do you know if there is multiple suction lines like for forward and reverse?
Thanks

 

[Simon C]

Not sure where the pilot filter is. Operators manual would tell where it is. Get that changed and hook a T-Tap in between the filter and the output line from filter to check pressure at idle and full rpm and oil at probably 120F or something like that.
Need to trouble shoot before buying repair parts. If you changed filters did you cut open the filters to check what was in the paper pleats.
Is there any active codes?
Simon C

 

[FSFarm]

I cut open the cartridge filter but not the spin on, the cartridge filter looked like a typical used filter with no excessive debris. The only warning light that goes off constantly is the coolent light, and sometimes the press brake alarm comes up right after you start it. What is/how does the pilot filter and lines work? I've worked on tractors and skid steers quite a bit, but we just got this machine so I'm trying to get it figured out? Thanks

 

[Simon C]

Your machine should have atleast one transmission filter unless it has a different set up. Do you know what year it is and how many hours?

Pilot pressure controls the main cotrol valve spools. You will need to get a manual on that thing as troubleshooting otherwise is way too costly. Maybe some independant mechanic with gauges can do some fast checks for you. Not sure if your unit has an interactive display that tells the pressures in the service display mode.
Komatsu fittings are a different thread for installing T-Taps, just so you know. They may have some quick check connectors, not sure what style.
Simon C

 

[FSFarm]

Its a 1998 with somewhere around 10k hours. Some places I look say it has a gear drive transmission and other places say it's a hydrostatic transmission, our local komatsu dealer couldn't even tell us which one it was. I think getting a good manual will be key, but we where going to try to find and clean the suction screen first.

 

[Simon C]

Suction screen first, and find out from dealer which is the Pilot filter as you can tee the line to check pressure. Those are simple tests needed to give some direction. 10000 hours could be a pump starting to go, but need to test first and check hydraulic schematic for other possible pressure losses.
Simon C

 

[FSFarm]

Sounds good, thank you for your help.