Changing hydraulic oil

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Paul Scherek
Member
Posts: 136
Hi all,
Can any one tell me please what is involved in changing the hydraulic oil in an XT, and what a current suitable type is? I can't find a drain plug, and am also uncertain as to whether any bleeding of the system will be required afterwards.
The manuals are very quiet on this topic....
Thanks, Paul
October 27, 2011 at 6:19 PM Flag Quote & Reply

Peter 334
Member
Posts: 118
Paul the book i have says transmax m it is easy to get super cheap has it need to change filter to , i relocated ours to futher under the body near the gear box longer hoses were needed, a sight glass fitted to see how much is in there ,i just filled the tank started the motor for a few seconds then toped it up untill it was right takes a couple of times it wont hurt the pump as the oil gets there pretty quick . cheers peter
October 27, 2011 at 7:49 PM Flag Quote & Reply

Dandj
Member
Posts: 367
Paul, there's no drain plug for the hydraulic oil.
To drain the oil, remove the filter element on the bottom of the reservoir (on the LHS rear of the engine). It holds about 4 litres of fluid.
What was the reason you want to change the oil, just maintenance or is there something wrong?
Before draining the oil, check for any leaks or wear on the hoses. I found one of ours had been chafing against a water pipe from the oil cooler so I took the opportunity of replacing and re-routing it slightly.
Renew the filter (Donaldson Part Number: P550162 or RYCO, Z79A) and top up with Automatic Transmission fluid (Transmax M (appears to be obsolete), Dextron 3 or equivlalent).

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David and Janet Ribbans, Oka 148

October 27, 2011 at 10:49 PM Flag Quote & Reply

Paul Scherek
Member
Posts: 136
Thanks Peter and David,
That all sounds easy. Nothing wrong David, just routine maintenance after sitting for 12 months while I build a camper body. Now I know why I couldn't find the drain plug - bet I can make an awful mess taking the filter off!
Cheers, Paul
October 28, 2011 at 8:15 AM Flag Quote & Reply

Dandj
Member
Posts: 367
Paul, one idea I read about recently is to puncture the filter with a screw driver and allow the fluid to run out slowly into a collector, instead of all down your arm.
Works for oil filters too.
This is the pipe that was chafing.



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David and Janet Ribbans, Oka 148

October 28, 2011 at 8:41 AM Flag Quote & Reply

Paul Scherek
Member
Posts: 136
Great suggestion, thanks David. I have used chopped-off 2 litre soft drink bottles to collect the spill from oil filters, but that's not so good for 4 litres of hydraulic fluid!!
Cheers.
October 28, 2011 at 9:54 AM Flag Quote & Reply

Peter 334
Member
Posts: 118
Dandj the oil for the hyd system Transmax m is made by Castrol and is still available to get, as i have brought some from Super cheep just 3 weeks ago, it is in the auto transmission area in a 1 ltr bottle ,cheers peter
October 28, 2011 at 7:34 PM Flag Quote & Reply

Dandj
Member
Posts: 367
Peter, yes, Transmax M is certainly still available but I suspect it's being superceeded. In the Castrol Aussie literature, they say it's an original Dextron 11 fluid designed to meet GM 1975 specs and they recommend Dextron 111 or Transmax Z for "severe duty" as an alternative.
From this Castrol Spec Sheet.
"CASTROL TRANSMAX M is suitable for a wide range of automatic transmission applications.... For severe duty applications CASTROL TO DEXRON® III or TRANSMAX Z (synthetic automatic transmission fluid) are recommended."
So either would be suitable.
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David and Janet Ribbans, Oka 148

October 29, 2011 at 8:44 AM Flag Quote & Reply

Paul Scherek
Member
Posts: 136
Well I managed to drain only two litres out of my hydraulics, tasefully redecorating my white shirt in a shade of pink on the way....
I could only find Penrite Dexron 3 locally, so it seems I now have a blend of 50% Penrite and 50% of whatever was in it before. Is this likely to be a problem?
It's a messy business changing oils and fliters, or am I just clumsy?
Cheers,
Paul
October 29, 2011 at 9:11 AM Flag Quote & Reply

Dandj
Member
Posts: 367
Paul, yes it's a messy business, always, gravity being what it is. The other 2 litres will be still around the system somewhere and won't drain out easily.
No, I doubt a mix of fluids will cause any harm. If the previous fluid was red it was probably the right stuff anyway. (Note Transmax Z is green). Unlike an automatic transmission, the Oka brakes and steering fluid doesn't get anything like the usage, but it is critical, so ensure you have no leaks afterwards. You should be OK because the filter and reservoir hoses are in the low pressure part of the system.
And no, normally there's no bleeding necessary unless you've replaced any steering box or brake servo components. The hydraulic pump will expel any air in the system as it returns excess fluid to the reservoir. I replaced a steering box seal without the need to bleed the system.
Test the brakes and steering before venturing too far and then check the fluid level again.
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David and Janet Ribbans, Oka 148

October 29, 2011 at 12:18 PM Flag Quote & Reply

Paul Scherek
Member
Posts: 136
Thanks David, glad I am not the only one who finds it a messy business! Brakes and steering feel fine, but I will give them a good workout and check the fluid before hitting the road. Cheers, Paul
October 29, 2011 at 6:34 PM