Had the trans and pump drive oil and filter changed. machine will move forward and reverse with plenty of power but then just stops. change engine speed move control lever forward and reverse can hear pump noise change but no go. Turn machine off, restart and away we go again. It is like and outboard engine cavitation where you have to let the prop stop before getting traction again. Any ideas?
Sounds to be sucking air.
Could I ask why..? Was this in an attempt to fix the problem or did the problem start after the oil was changed..? Your OP isn't totally clear. Also what oil are you using..? These particular machines are very sensitive to the correct oil.
Prob existed before change. Oil and filter changed because machine had been unused for a couple of years. Cat agent Westrac changed the oil with cat 30weight, said 10w was too light for our warmer climate.
I would stand corrected but I thought that the oil recommendation for that model was critical and the only thing that could be used was 10W hydraulic whatever the ambient temperature - no ifs buts or maybes. Send a PM to Cmark of this parish. He's an expert on those machines and from his location on the Gold Coast can probably give you sound advice specific to your climate.
Yep, agree with Nige. 10W is specified for -20 to +50°C.
All that said, if you can hear the pumps loading up then your problem may not be related to the oil viscosity. It sounds more like the brakes are coming on which would be an unusual fault in these machines. You may be into some moderate troubleshooting here. If Westrac came out and changed the oil and the problem persisted, what do they have to say about it? What is the exact serial number? Is there a brake release pump in the cab and if you open the left door can you see a U shaped tube on a manifold?
21z05651
OK Westrac came out again to fix an oil leak (had to lift the cab), asked the service mechanic about the oil weight in the trans, said 30w should be OK and that the machine should always be operated at full throttle. Took the machine for a spin and yes at full throttle will move ok. Problem now is that often the right hand track holds and the machine turns in circles press the LH pedal and the machine locks up and stops, reverse the machine and can move forward again and operate as normal, then above problem re-occurs. I have adjusted the RH pedal linkage to back it right off and make sure it is not a sticking linkage problem but no change. Thinking that I will change the trans oil to 10w hydraulic (another $350 for oil) and see if that fixes it.
Haven't got access to sis at the mo (on holiday) but is 21z the older model with the separate pump drive gearbox? Agree the hydraulic oil should be 10w, but surely the gearbox will be 30w tdto?
Yes has separate pump drive which has 30w tdto. The hydrostatic drive is the problem. 30w has been put in it, the drive has started to play up, not sure if putting 30w rather than the 10w may be the cause
Now you've clarified things, 100% on 30w being too heavy in the hystat circuit. When you change it, I suggest you cut your return filters open for a crap check, and clean your suction strainer at the same time. Bit concerned about this track-locking issue, though. Have you had a look in your final drive for debris, stray teeth, etc? Don't want to be the prophet of doom, but that doesn't sound like a hystat issue to me.
Seconded that........ pull the mag plugs on the final drives and see what's on them. Take photos and post them back here if you want an opinion.
Ok changed hydo drive oil to 10w, no change, pulled final drive magnetic plugs no metal. Only get movement at full revs, RH track still sticking and have to bang it loose by jabbing the left hand pedal. Got Westrac out they messed around for a few hours fault finding but still no joy, coming back today to lift the cab and take the hydro cover off. Fingers crossed something can be found without too much more expense.
Well after 2 visits, tilting the cab, taking the hydrostatic drive cover off and checking linkages and checking pressures and god knows at what cost Westrac has diagnosed the problem as the right hand travel motor return pressure being too high preventing the right track from fully operating. Now for the quote for a recon!!!!
Are you sure they didn't say high case drain pressure? High return pressure sounds like an unusual diagnosis.
Yes it is case drain pressure, should be no more than 2lb but mine is 25lb at idle and goes up to 60lb under revs. There are no reman travel motors available at the moment and a new unit is $20K, so the options are to rebuild my motor and have fingers crossed that there is not too much wrong with it or find a used one.
The travel motor on my machine is part# 6E 3516 does anyone know if the earlier model 963 travel motor part # 9T1463 is interchangeable?
When you get it apart, you'll need to carefully assess how it's failed and decide whether any debris has gone back up the drive loop. If it has, there's a good chance the pump is damaged as well. If you're lucky, it will just be a broken universal joint.
Yes, it will fit. You may have to swap the drive hoses as well.
If it was me id drain the HPCU again and strin the oil and swap filters to make sure you have no fringment in there. Unless you can account for all the broke pieces