Yanmar 2GM20F gearbox oil

H

hunter323

Well-Known Member
Joined
16 May 2010
Messages
131
Visit site
Oil again - the kanzai KM2P gearbox plate says use SAE30 HD oil - One yanmar site says use same as engine ie 15 -40 multigrade another yanmar site says use SAE30. Whats best and what does HD mean. The whole thing seems strange when Kanzai is a subsidiary of Yanmar apparently!
 
Last edited:
Oil [again!].

hunter323 said:
Oil again - the kanzai KM2P gearbox plate says use SAE30 HD oil - One yanmar site says use same as engine ie 15 -40 multigrade another yanmar site says use SAE30. Whats best and what does HD mean. The whole thing seems strange when Kanzai is a subsidiary of Yanmar apparently!
Click to expand...

The inconsistency is strange but may be indicative of the fact that either will do. I can't believe that the gearbox will notice the difference. HD indicates that the oil contains some anti-scuffing additive although probably not a lot. You need to watch out for the fiercer a/s additives e.g in GL5 gear oil as they are chemically active and can attack brass/bronze components in older gearboxes that weren't specified to cope with them.
 
SAE 30 HD.

Thats interesting. A bit of Googling and I find Comma HD 30 a monograde SAE 30 diesel engine oil to API CC.

Could be what a lot of owners of older engines have been looking for.
 
Yanmar KM2P gearboxes

hunter323 said:
Oil again - the kanzai KM2P gearbox plate says use SAE30 HD oil - One yanmar site says use same as engine ie 15 -40 multigrade another yanmar site says use SAE30. Whats best and what does HD mean. The whole thing seems strange when Kanzai is a subsidiary of Yanmar apparently!
Click to expand...

If you follow the operators manual and use Marine gear oils or any specialist gear oil you may suffer clutch failure. This is confirmed in a reply to me from Yanmar International. A straight SAE 20 or 30 engine oil seems to be the best solution, this again is their recommendation they stated this oil will provide the best performance and longevity of live. The use of multi grade, can in hot condition lead to a premature breakdown of the oil. This is from info supplied by Yanmar International. It seems the gear box label description could equally apply to engine or gear box oil. Yanmar have agreed their manual is confusing and will do something to alert future customers.

To add to the confusion there is an advert around stating "Yanmar recommend Castrol Marine Gear Oil".

The API oil stds have primarily been formulated to reduce oil emissions through the exhaust that reduce the life of catalytic converters, hardly applicable to boats. This is at the cost of friction reducing additives so the argument goes on!!!!!!!!!!!! This is also from info supplied by Yanmar International. I hope this helps. Seafarian
 
hunter323 said:
Oil again - the kanzai KM2P gearbox plate says use SAE30 HD oil - One yanmar site says use same as engine ie 15 -40 multigrade another yanmar site says use SAE30. Whats best and what does HD mean. The whole thing seems strange when Kanzai is a subsidiary of Yanmar apparently!
Click to expand...

Single grade oil is always better if you can get away with it in marine applications. I certainly would not use 15-40 multigrade in the engine or gearbox. I would however use SAE30 in both.
 
fishermantwo said:
Single grade oil is always better if you can get away with it in marine applications. I certainly would not use 15-40 multigrade in the engine or gearbox. I would however use SAE30 in both.
Click to expand...
Why/Why not? Statements like that require an explanations to support them.
 
VicS said:
Why/Why not? Statements like that require an explanations to support them.
Click to expand...

Older style engines with flat tappets require an oil with a reasonable amount of ZDDP. In a marine environment where the engine temperatures are more stable there is no need for all the additives required to make a multi grade oil. For the last 26 years or so I used 40 grade mono in my Gardner engine and gearbox, old engine old style oil. Kubota auxillary got the same oil and at 16,000 hours runs extremely well. If I was to use a multi grade in an older style marine engine such as my Volvo in my yacht I would use 20-50.

I would be extremely surprised if Yanmar make oil.


Plenty of webpages dedicated to oil. Just avoid modern oils in old engines.
 
So not so much an objection to an oil being a multigrade rather to the lack of the anti wear additive used in older oils.

add that to the high TBN which seems to be what Vyv objects to and old engines seem to be doomed!
 
My Yanmar manual (p21) says:-
Engine lube oil API classification CD, SAE viscosity 15W40
Oil for marine gear SAE viscosity 30

CD classification is sometimes hard to find but the main thing is to use non-synthetic oils with no enhancers/additives
 
ghostlymoron said:
My Yanmar manual (p21) says:-
Engine lube oil API classification CD, SAE viscosity 15W40
Oil for marine gear SAE viscosity 30

CD classification is sometimes hard to find but the main thing is to use non-synthetic oils with no enhancers/additives
Click to expand...
My Yanmar manual (p29) states:-
"Use marine gear oil"
Gear oil is a no no as it will affect the clutch.

SAE30 or SAE30 HD seems to be preferred oil for most conditions.
 
You must log in or register to reply here.

Share this page

Top