I used to buy from Morris Oils. As you say based in Shrewsbury but depots in many places. A 5 gallon drum, two fills for my BMC 2.5 litre engine, was free delivery and very reasonably priced.Morris oils in Shrewsbury near me produce mineral oils of various viscosity suitable for simple marine diesel engines. Available at chandler's around here.
Synthetics are meant for modern high performance diesel engines powering road vehicles. Most boat engines are based on simple industrial engines not of recent vintage.Why not synthetics or semi-synthetics? There is nothing in the Yanmar spec that suggests that. Any good oil will exceed CF, which is somewhat obsolete.
An obvious old school choice would be Rottela T4.
Google API and SAE classifications. For even more confusion (bluring the synthetic-conventional line), read up on base oil groups. Nearly all conventional engine oils are a mix of group II and group III oils, and both of these blur the line between conventional and synthetic in terms of chemistry and performance. https://www.machinerylubrication.com/Read/29113/base-oil-groups
ENGINE OIL
Engine Oil Specifications
Using engine oil that does not meet or
exceed the following guidelines or
specifications may cause seizure of parts,
abnormal wear and shorten engine life.
Service Categories
Use an engine oil that meets or exceeds
the following guidelines and classifications:
• API Service Categories CD, CF, CF-4,
CI and CI-4.
• SAE Viscosity: 10W-30, 15W-40. Engine
oil 10W-30 and 15W-40 can be used
throughout the year.
NOTICE
• Be sure the engine oil, engine oil storage
containers and engine oil filling
equipment are free of sediment or water.
• Change the engine oil after the first 50
hours of operation and then at every 250
hours thereafter.
• Select the oil viscosity based on the
ambient temperature where the engine
is being operated. See the SAE Service
Grade Viscosity Chart (Figure 5).
• Yanmar does not recommend the use of oil additives.
The place to buy oil is not at a garage or a supermarket, but at a motor factors, or preferably at a specialist oil vendor.I'm finding it increasingly difficult to find mineral oil for my Yanmar 4JH4E.
My local garage only stocks synthetic oils or semi synthetic, as does my local super market.
Yanmar say 15W40 API CI-4 CF-4
Yanmar branded oil is now £50+ for 5L
I need 6L for and oil change.
I've found a supply of Comma 15W40 , says "API SL CF CG-4" on the label, is that suitable for my Yanmar?
I've tried googling API SL CF CG-4, but can't find anything that makes sense to me.
Like you went through this back in February for my Yanmar 4JH2-E.
Have a look at Shell Rimula R4 X 15W-40.
I ordered a 20Lt drum from www.opieoils.co.uk back in February which came with free delivery. Cost then was £80.95 with a 10% discount. There are quite a few recommendations for Opie Oils from other "oil" threads on this forum.
This drum should last me 3-4 years and works out somewhat cheaper than the 5 Lt can.
I've used COMMA mineral oil in my Beta 25 for years now - bought from my local car factor.
Synthetics are meant for modern high performance diesel engines powering road vehicles. Most boat engines are based on simple industrial engines not of recent vintage.
Synthetic can itself form nasty ‘varnish’ and sludge if run at low revs or short runs over the life of an engine. I know this is a high performance petrol - but check out this clip (a minute or so from 6:03 in):It does not say that in the manual. It said "meets or exceeds." Does Yanmar say that somewhere?
Is the concern leaks (synthetics can remove old sludge) or something else?
If you get down to it, you won't find a multi-vis without group II base stock as a blending agent, and that actually makes it a semi-synthetic in all practical ways. Just sayin'.
Not sure why people with small yacht engines get obsessed with oil when the demands on it are so modest. The typical yacht engine does 100-150 hours a yea and spends most of the year idle for long periods. My car averages 26 miles an hour, so 150 hours is equivalent to 3900 road miles. My car has a 3 cylinder 1l engine boosted to 128hp, rather more demanding than my 1.2l 3 cylinder Beta which produces a maximum of 29hp, but normally only runs at half that. So the "change every year" which is common is very conservative - and yacht engines, even if neglected rarely wear out.Do you change at recc'd hours or more frequently ?
Of course it meets spec designed for - but its when you want to over-run the hours or usage that its 'quality' then shows its limitations.
Absolutely agree. But, I still wouldn’t use either supermarket/‘bargain’ mineral nor synthetic. The former for the sake of a few quid. The latter because it’s the wrong thing, for ours, according to Beta…Not sure why people with small yacht engines get obsessed with oil when the demands on it are so modest. The typical yacht engine does 100-150 hours a yea and spends most of the year idle for long periods. My car averages 26 miles an hour, so 150 hours is equivalent to 3900 road miles. My car has a 3 cylinder 1l engine boosted to 128hp, rather more demanding than my 1.2l 3 cylinder Beta which produces a maximum of 29hp, but normally only runs at half that. So the "change every year" which is common is very conservative - and yacht engines, even if neglected rarely wear out.
Different if you are operating commercially. When I had my boat on charter it averaged 450-500 hours a year and the oil and filter were typically changed 3 times a year. When I sold it at 3500 hours it was running as well as it did new.
Much more important to look after the cooling system and run the engine hard from time to time than fret about the spec of the oil.
I'm in the 'biz' - but when I buy Lub oil for my Volvo XC70 ... my Renault Master Van ... my Generators ... Lawn Tractors .... boat engines ............. I choose based on 10-40W ... or whatever W rating needed ... and even in my old Perkins 4-107 ... its generally 10-40W Semi Synthetic ... and its been fine for nigh on 20 yrs with me ...