OH-HM 42 oil?
- Thread starter geoweaser
- Start date
RjCorazza
Elite Member
I went partially down the rabbit hole, and it seems that HM is an ISO performance specification (ISO 11158 HM). The 42 is an ISO viscosity rating. I could not find any reference to OH.
I think you would want to call a Zetor dealer, or perhaps a Zetor owner here will be able to offer more specific advice.
I think you would want to call a Zetor dealer, or perhaps a Zetor owner here will be able to offer more specific advice.
Thanks for looking into it.
I just found this description on a different page in the manual, which I'd overlooked: OH-MH 42 "meets the requirements for high-pressure hydraulic oil identified abroad as HM 32". Does that open up any possiblities for readily available hydraulic oil?
I just found this description on a different page in the manual, which I'd overlooked: OH-MH 42 "meets the requirements for high-pressure hydraulic oil identified abroad as HM 32". Does that open up any possiblities for readily available hydraulic oil?
RjCorazza
Elite Member
I am assuming the 32 and 46 are ISO viscosity grades. If that's the case it would seem that your manual is saying a slightly thinner hydraulic oil of 32 is also acceptable.
If your power steering is separate from the transmission / hydraulic sump, I would start checking various hydraulic oils available in your area that meet the ISO specification ISO11158 for HM hydraulic oil.
A similar model Zetor manual has the same OH-HM 32 listed, but also adds "This oil corresponds to high pressure hydraulic oils according to ISO 6743, ISO -L- HM 32".
If your power steering is separate from the transmission / hydraulic sump, I would start checking various hydraulic oils available in your area that meet the ISO specification ISO11158 for HM hydraulic oil.
A similar model Zetor manual has the same OH-HM 32 listed, but also adds "This oil corresponds to high pressure hydraulic oils according to ISO 6743, ISO -L- HM 32".
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