Engine Oil as Hydraulic Fluid??

[Dimonsof]

We used 15W40 on both our Liebherr Shovels in Namibia (R984C and R9250C) and had no issues. Actually, local Liebherr dealer recommended to do so as well.

Dima

 

[Nige]

Hi Nige,

I work for a mining company and have few Hitachi excavators like EX 3600, EX 5500-5, EX 5500-6 and Hitachi recommends zinc free hydraulic oil.

I have been using zinc free hydraulic oil since day dot but still see zinc levels in used hydraulic oil upto 30-50 ppm and all excavators are going through varnishing issues in pumps and valves which result in jerky hydraulic operations.

I have checked with some other mining companies here in Australia and they also experience zinc levels in used zinc free hydraulic oil from these excavators. and they are seeing levels of zinc more than 100 ppm.

Please note that the hydraulic filters used here are not usually fleet guard filters which are known for having leaching zinc in the oil at operating temperatures for hitachi hydraulics. Hydac filters are predominantly used in these applications.

Can you please shed some light on where that zinc in oil would be coming from?

Thanks

Zee

Sorry for not replying sooner Zee. This thread must have fallen through the cracks while I was out of the country due to a family bereavement in March.

My thoughts on this are that you have to follow the process by analyzing the bulk supply tanks followed by the field service truck as a first step. However IMO it's unlikely that one or other is the source as the oil has to be hotter than ambient temperature for leaching to take place at anything approaching significant levels. It's a well to tick the box though.

If the filters being used are anything other than Hitachi OEM then send them to a lab that has the capability to test them for leaching for at least 1 week (preferably more) at normal machine operating temperatures, say 85 DegC minimum. The lab will probably ask for both new and used filters for their tests. We used https://www.oillab.com/ and I can thoroughly recommend them. However I'm sure you can find somewhere in Oz with similar capabilities.

If the filters come back negative then the only other thing is if you are not using Hitachi OEM hoses then there may be some zinc content in the hose fittings used to make them. Again your lab could subject a few samples of hose fitting to an extended leach test with hot oil.

 

[Karl Robbers]

I am aware of the horrible things that can happen to wet brakes when the wrong oils are used, but one example puzzles me.
I once worked for Barminco, an underground contractor, running Cat AD55 and 55B trucks alongside the same trucks run by the client. Barminco switched to engine oil in the hydraulics, which of course meant the brakes as well, while the client continued using hydraulic oil. Same environment, same loadings and nothing seemed to go wrong. The two Atlas Copco MT 6020's that the client introduced used a totally different suite of oils as I recall. Horses for courses I guess - the MT6020 was like a model T ford compared to the Rolls Royce Cat AD55B.

 

[apetad]

Well, My main inside man at Bobcat tells me that the new and "improved" motor oils have had important ingredients removed to comply with the new federal emissions requirements regarding low-ash and so on, MAKING IT NO LONGER SUITABLE for use in hydrostatic systems in Bobcats of any age. Now they use a high grade hydrostatic hydraulic fluid similar to Case Hy-Tran Ultra, or our Chevron 1000 THF. New Saying: "If it ain't broke the Feds will figure out a way to break it" NOW Bio-Diesel 5% Minimum is causing a major pain with tier-4 aftertreatment too!!!

 

[attaboy]

Well, My main inside man at Bobcat tells me that the new and "improved" motor oils have had important ingredients removed to comply with the new federal emissions requirements regarding low-ash and so on, MAKING IT NO LONGER SUITABLE for use in hydrostatic systems in Bobcats of any age. Now they use a high grade hydrostatic hydraulic fluid similar to Case Hy-Tran Ultra, or our Chevron 1000 THF. New Saying: "If it ain't broke the Feds will figure out a way to break it" NOW Bio-Diesel 5% Minimum is causing a major pain with tier-4 aftertreatment too!!!

Well my response here may be off-topic, as I am Not a commercial operator just a homeowner/homesteader with privately used diesel tractors, going back to a 1950 Austin Western Super 88H. So you guys now gotta use 5% bio-diesel? That sucks .. like the red dye in off-road being water soluble.

My comments on Tier 4. Now for me, not being in a commercial enterprise and out in the woods as it were, how is it that in order to meet Tier 4 criteria in tractor-trucks and diesel powered tractors .. require the use of an after-treatment fluid, while the latest locomotives have gone from 16 cylinders down to twelve cylinders while still putting out 4,500 horsepower, without the use of any after-treatment fluid? Perhaps this is a matter of scale? The older I get, the lesser I knew

And as in my original post here in this thread, my sweet little Komatsu D-21 P5 specifically calls for motor oil to be used in ALL systems, Even in the final drives.

 

[Willie B]

Dresser TD7G is one example of the manual calling for engine oil in the transmission including hydraulic pumps, and gears, and steering clutches & brakes. Then they go one saying it must meet TO1 specs, and be #10. I've never seen an oil meeting all those specs. I'm going with Hy-Tran.

 

[Nige]

Dresser TD7G is one example of the manual calling for engine oil in the transmission including hydraulic pumps, and gears, and steering clutches & brakes. Then they go one saying it must meet TO1 specs, and be #10. I've never seen an oil meeting all those specs. I'm going with Hy-Tran.

You might be better using an SAE10W TO-4

 

[M Leach]

When in doubt go with the oem recommendation.

 

[fast_st]

Well, My main inside man at Bobcat tells me that the new and "improved" motor oils have had important ingredients removed to comply with the new federal emissions requirements regarding low-ash and so on, MAKING IT NO LONGER SUITABLE for use in hydrostatic systems in Bobcats of any age. Now they use a high grade hydrostatic hydraulic fluid similar to Case Hy-Tran Ultra, or our Chevron 1000 THF. New Saying: "If it ain't broke the Feds will figure out a way to break it" NOW Bio-Diesel 5% Minimum is causing a major pain with tier-4 aftertreatment too!!!

Easy way to find the 'improved' motor oils, look at the round stamp and see if it says 'energy conserving' that's the evil stuff, makes motorcycle clutches slip like crazy and causes lots of other equipment issues, loss of brakes, clutches. Although an oil change seems to fix it in short order.

 

[Norbert77]

Just bought a 86 - ish John deere 693B excavator yesterday. Long weekend here, want to get some work done. Being a maintenance man, I want to change out everything including the hydraulics fluid. I read that the deere 690 chewed up pumps on hydraulic fluid and then engine oil fixed that. I don't know what is in it, it smells a little like both engine oil and hydraulic fluid. What should go in it?