What four stroke oil?

[Stik-ugly]

My 99 40 hp four stroke Merc [yamaha power head] is due for a service and I usually carry out the service myself. The previous service was carried out by local marine mech but they have stopped operating due to a fire. Initially they used Yamalube and so did I and then they changed to Hitec Oils in a 10 w 30 grade.No one in the local area sells Yamalube and I'm unsure who deals with HItech so what is another good brand of 4 stroke marine oil? I really don't like changing brands to much but it looks as if I will have to.Any opinions on Quicksilver oil and what grade? and also opinions on multigrades or just stick with say straight 30 grade oils?

[Stik-ugly]

I also forgot to add any advantage using synthetic to mineral base oils in this age of motor?

[Noelm]

I would use whatever grade the manufacturer recommends, and as a general rule, use the manufacturers own oil, even though it may just be something else in their bottle.

[Spaniard_King]

Any 10W-30 SG or SJ rated engine oil would be fine you could even go 10W-40 in that engine and it will be fine.

[Roo]

I use the same oil I use for my diesel landcruiser. Last change was Caltex Delo 400. Next change will be gulf western TD XDO 15w/40 Ci4. The detergents in diesel oils help keep an older motor clean. I have an '03 Yamaha 40. The gulf Western is easier to get and last month supercrap auto had 20L drums for under $70. Cruiser uses 11.5 of that so always have a bit spare for the Yamaha.

Oh and most diesel oils are suitable for mixed fleet.ie petrol motors too.


Sent from my iPad using Tapatalk

[gazza2006au]

i done a full rebuild on a 98 model 25hp mercury 4 stroke and used Castrol worked great https://www.whitworths.com.au/main_itemdetail.asp?cat=135&item=55022&intAbsolutePage=1

u can get it from super cheap auto