235 C surging when traveling forward loading up turning

My 235 started surging on travel mostly forward and when I go to turn will almost stall it out .if I back off the travel pedal and do a partial foot application it's ok or if I stop and get back on it it will be fine for a few mins. I am going to start with changing all the filters today especially the pilot filter. Any other ideas or suggestions wanted. Thanks guys. This was a fully serviced machine I bought last year and has worked flawlessly till yesterday .

It is something like 27 years since I played around with a very recalcitrant 225, something tells me that it sounds like a signal pressure issue, the pumps are getting a signal to go to full swash when other valves aren't fully open to take the flow, maybe a sticking valve, broken spring or some grub in the system. Sounds like you will need someone who really understands those old systems, the latest machines all the fitters work on have computer diagnostics, so they may not be much use to you.

Wombat

I changed the pilot filter it was pretty cruddy no metal just dirty this seems to have remedied the problem I have ordered a hydraulic pressure test kit and will do some pressure checks and more diagnostics could wear in the travel pedal valve body this thing has had the power turned up on the travel it doesn't slow down much

Thanks wombat for the reply.


[quote="Wombat"]It is something like 27 years
since I played around with a very recalcitrant 225, something tells me that it sounds like a signal pressure issue, the pumps are getting a signal to go to full swash when other valves aren't fully open to take the flow, maybe a sticking valve, broken spring or some grub in the system. Sounds like you will need someone who really understands those old systems, the latest machines all the fitters work on have computer diagnostics, so they may not be much use to you.

Wombat[/quote]