Engine Oil
- Thread starter Sailfree
- Start date
dom
Well-Known Member
sailorman
Well-Known Member
I bet that fully synthetic
Heckler
Well-Known Member
PuffTheMagicDragon
Well-Known Member
I have been trying to understand all that was written in this thread. Unfortunately it seems that my age is preventing me from reaching a clear conclusion. 
The engine on my boat is a Volvo MD2b that dates back to 1973. It is certainly not 'high performance' nor would I say that it classifies as 'heavy duty' since it is only pushing a 32 foot sailing boat. My questions are: "What oil should I be looking for to use in this engine? Failing this, what are possible substitutes? What is to be avoided?"
If someone would kindly provide a simple answer that is clear enough for me to understand it would please me no end.
Thank you in anticipation.
The engine on my boat is a Volvo MD2b that dates back to 1973. It is certainly not 'high performance' nor would I say that it classifies as 'heavy duty' since it is only pushing a 32 foot sailing boat. My questions are: "What oil should I be looking for to use in this engine? Failing this, what are possible substitutes? What is to be avoided?"
If someone would kindly provide a simple answer that is clear enough for me to understand it would please me no end.
Thank you in anticipation.
Tranona
Well-Known Member
I have been trying to understand all that was written in this thread. Unfortunately it seems that my age is preventing me from reaching a clear conclusion.
The engine on my boat is a Volvo MD2b that dates back to 1973. It is certainly not 'high performance' nor would I say that it classifies as 'heavy duty' since it is only pushing a 32 foot sailing boat. My questions are: "What oil should I be looking for to use in this engine? Failing this, what are possible substitutes? What is to be avoided?"
If someone would kindly provide a simple answer that is clear enough for me to understand it would please me no end.
Thank you in anticipation.
The simple answer seems to be clear. Use a mineral CF spec oil, either 10 40W or 15 40W. This is the closest to the original recommendation. Easily available in UK, and no doubt in Malta. Often labeled for use in older diesel cars. You will find the specification on the back of the container. A good indicator is price, it is usually far cheaper than the modern synthetic oils used in high performance diesels.
Sans Bateau
Well-Known Member
Ideally a mineral oil with a API CD spec. Although in the UK this will be hard to find. You can as in previous posts find it in France. Failing that a mineral oil with a spec of API CF should be easy to find. Avoid synthetic or semi synthetic whatever the man in the shop says.
PuffTheMagicDragon
Well-Known Member
CF it shall be then.
I still have some 15W40 CD containers and was wondering what to get when they finish because I was under the impression that CD is obsolete.
Thank you for clear answers!
I still have some 15W40 CD containers and was wondering what to get when they finish because I was under the impression that CD is obsolete.
Thank you for clear answers!
VicS
Well-Known Member
Vyv Cox has explained why oils with a higher/ more recent API service classification may be unsuitable for older yacht engines but what is the objection to synthetic or semi-synthetic oils ?
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Sans Bateau
Well-Known Member
Vics, I cant answer that technically, other than they are 'too good' for older engines, hopefully Vyv may shed some light on it. What Ì can say though, many years ago I was buying oIl and filters for a VP 2002 from a local marine engineer, I picked up a pack of synthetic oil of the correct grade although in ignorance most likely the wrong API. He steered me to a mineral CD oil. He told me he sees many engines loved to death where owners used the best oil although the wrong oil. Glazzed bores was the biggest problem I recall.
single
Well-Known Member
So after reading all this, i'm assuming this stuff isn't doing my engine any good? (Thornycroft T95)
View attachment 50233
View attachment 50233
Sans Bateau
Well-Known Member
Thats probably a good choice. Its mineral and API CF.
VicS
Well-Known Member
It meets API CF spec.
Provided its the correct viscosity there is nothing to suggest its doing any harm! Its even a mineral oil if that is relevant!
vyv_cox
Well-Known Member
Only for the reasons I give on my website. Synthetic base oils are expensive and thus the lubricants blended from them tend to be highly additive and because they are intended for extreme duties they often have high TBN. Almost every 'classic' car user forum warns against using them in old engines, based on adverse experience.
In rotating equipment that doesn't have to contend with combustion products in the oil, e.g. aircraft and industrial gas turbines, multi-stage pumps and compressors, synthetics perform brilliantly and have solved major reliability problems in many examples I am aware of. The lubricant reservoir on most aircraft engines with outputs in mega-watts is remarkably small, only 10 or 15 litres. These oils are usually just the base oil with almost nothing else. Synthetic motor lubricants may comprise 30% additives.
RichardS
N/A
I'm certainly not recommending that anyone does what I do ..... but I've always taken a rather cavalier attitude to manufacturers recommendations for oil changes for engines, gearboxes and diffs and have preferred to look at oil discolouration, smell the oil for burned carbon and feel between my fingers to see whether its viscosity and smoothness seems right before deciding whether it is time for an oil change.
I first used fully synthetic oil back in the 70s when it became available although in those days it would have been something like £100 a gallon based on current prices. The first time I stripped an engine which had been run on fully synthetic oil I was amazed how little discoloration on the metallic surfaces had occured. Since then I have only ever used fully synthetic oil in cars, motorbikes and even lawnmowers. The longest I can remember extending the maufacturers oil change recommendation was by a factor of almost 3x before I decided that the oil was approaching the end of its useful life.
My boat engines are Yanmar YMs so a reasonably recent design. I am running them on semi-synthetic because I decided that fully synthetic is too low a viscosity and, being in the Med, the engines are never run cold. I can get semi-synthetic at 15w-40 which meets the Yanmar viscosity recommendation. The oil is still in excellent condition after 2 seasons so I have not changed it yet but might do so this year.
As, I say, I don't recommend anyone follows my advice but, after over 45 years of working on engines, the only main/big/small end bearings I have ever had to replace were on engines running on mineral oil.
Richard
lw395
Well-Known Member
If you look on certain motorbike sites, a lot of very high mileage riders on quite varied machines will agree with you.
And others won't...
Some people seem almost as enthusiastic about their chosen oil regime as about their chosen marque of motorbike.
Some of them get very technical, with oil analysis for wear particles etc etc.
Worth a google perhaps..
Sailfree
Well-Known Member
Always felt it's more important to change oil frequently.
When I bought in 1965 a Honda 305cc super sports I changed the oil every 500 mls or so - yes I find that unbelievable now but a friend had a 250 cc super sport that he neglected and thrashed. The 250 beat mine on acceleration until I stopped changing the oil as I was getting rid of it and I thrashed it more. Then mine started to out accelerate the 250 as it should. I felt engine was still tight due to frequent oil changes.
Don't so much want the Honda bike back just the youth and looks I had then! Sad!
When I bought in 1965 a Honda 305cc super sports I changed the oil every 500 mls or so - yes I find that unbelievable now but a friend had a 250 cc super sport that he neglected and thrashed. The 250 beat mine on acceleration until I stopped changing the oil as I was getting rid of it and I thrashed it more. Then mine started to out accelerate the 250 as it should. I felt engine was still tight due to frequent oil changes.
Don't so much want the Honda bike back just the youth and looks I had then! Sad!
single
Well-Known Member
A mechanic in the boatyard suggested using this oil http://www.ebay.co.uk/itm/301499343543
So is this ideal for a Thornycroft T95?
So is this ideal for a Thornycroft T95?
sailorman
Well-Known Member
Performance standards
Suitable for use where the following performance is required:
• ACEA A2/B2/E2
• CCMC D4/PD2/G4
• API CD/CE/
CF-4/SJ/SH/SG
Looks like it as would 15>40 from a supermarket, i would suggest 30 grade too light / thin for an old engine
RichardS
N/A
10W-30 is quite thin for old design engines. What is the recommended viscosity for your engine? If the recommended is oil is 20W-50 or 15W-40 I would be a little concerned that the linked oil is too thin unless you are running in a very cold climate where a thin oil might be preferable.
Richard
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