Yanmar 3GM30 gear oil

[JerryHawkins]

There is a plate on the gearbox which says "20/30 HD". What does this mean? My local chandler says I should just use ordinary car engine oil, is he right? I could just buy the official Yanmar oil, but its bound to be several times the price!

Similar question regarding oil for the engine itself - what should I use. I've currently got Castrol GTX Magnatec (Diesel) oil. Is this OK?

Thanks,

Jerry

 

[steve_cronin]

All I can relate is my own experience.

When we had a Yanmar in our last boat I bought the official Yanmar workshop manual.

This specified engine oil for the standard gearbox as per your chandler's advice. I used Magnatec Diesel in that engine for seven seasons and when the boat was sold the surveyor was impressed with the engine's condition. I have a great respect for Wakefield's oils and have used them exclusively (except when unavoidable) in all the engines I have ever owned.

Incidentally, I discovered by checking the cross referencing in the back of both the Purolator and Fram oil filter catalogues that my engine (a 2GM20FW) shared the oil filter of the Mazda 323 which is available at a fraction of the cost of a genuine Yanmar filter (which I would assume they outsource anyway) from car accessory shops. If it's still in warranty though I wouldn't invite a claim rejection just because the filter isn't painted grey!

Steve Cronin

 

[JerryHawkins]

Thanks Steve.

No warranty worries - the engine is 12 years old with just over 1000 hours (250 of which I've put on). If engine oils is OK, then could I use the same Magnatec Diesel oil I use in the engine?

Cheers,

Jerry

 

[steve_cronin]

I did

Steve Cronin

but ring Peter (I think there are three of them) at Power Marine Bursledon (023) 8040 3918 if in doubt

 

[kgi]

Steve any other part numbers you located for the 2GM would be much appreciated......cheers.....keith

 

[steve_cronin]

Re: Other parts

Well I wasn't sure how this would be received but:-

I once fitted a Jabsco "equivalent" impellor but when I decided to replace it two years later I had the very devil of a job to get it off the shaft whereas the before & after slid on and off easily. Could have been a burr but none was evident.

Steve Cronin

 

[JerryHawkins]

Thanks Steve. NM.

NM

 

[snowleopard]

take care...

don't have the specs for conventional gearbox but for the saildrive it differs from engine to engine (1GM uses 30 grade, 2&3GM use 90 grade) so don't guess. the 20/30 on your gearbox probably means it's the type used on the 2 & 3 cyl models. I have 3GM30 and use EP90 hypoid gear oil from car garages.

 

[Guest]

I use the Z510 and A770 13mm x 750mm drive belts from Fenner power transmissions on my 2gm - branches in most large cities.

Dont use the belts from car spares places, they are mostly 12mm, sit at the bottom of the V and have a life measured in hours. Take along your Yanmar belts to get them to match.

As far as gearbox oil is concerned, I would advise caution. On the 2 GM (I dont know whether the 3GM is similar) the clutch is a cone affair, and as it wears over the years you can have slippage probs with too good an oil. Best use Yanmars product - after all, the 2GM box holds very little oil anyway.