Fully synthetic engine oil

Marlene

Well-Known Member
Joined
2 Jul 2015
Messages
141
Visit site
My little boat has two 30 year old ford Sabre engines.
Both running well and I obviously would like to
keep them running for many more years. Should I
Change to a fully synthetic oil ?
Is fully synthetic oil suitable for these old turbo diesels?
Will it increase the longevity of the engines?
I would rather keep these old girls going rather
Than go to a computer controlled engine where you need
A highly paid computer scientist to come in to change a jubilee clip.
Your opinions please.
 
Agree , try speaking to the tech department at Morris Oils. They make lubes for everything and are super knowledgable and very helpful.
 
Marlene A highly paid computer scientist to come in to change a jubilee clip. Your opinions please.[/QUOTE said:
Love that Sentence Marlene!
Do not use a Fully Synthetic oil in the Sabres
How do I know?
Bloody old Mate and watched the wheel get invented, nuisance though, the guy who invented the bloody axle was late and his mate had forgotten to invent grease!
So, before any of our more intelligent Forumites chip in and tell me to wallow in my own Lubricant
I have used a semi synthetic 15 W 40 in the Sabre Turbos for years
Cheap as Chips (cook well too) from a Motor Factor near you
Buy a 25 litre tub
One 'Caveat' you don't/ didn't say what size Sabre Turbo's you have?
Not that it might make a deal of difference
If I don't reply until the next day by the way, It means I am well oiled!
:D
 
I was told by our Mobil 1 rep that the general rule is to only use synthetic from new and not to switch to synthetic on an engine that has run for years on mineral. The reason was that synthetic has more cleaning effect and will wash away the carbon deposits that are present in various parts of the engine especially behind the lips on seals and the engine will most probably start to leak. Don't know how true this is but sounds pretty logical and I have heard this several times in the motor and boat trade. So my Mercuiser V8 gets fed mineral, whereas both my Saab turbos and Jaguar get synthetic as thats all they have ever tasted since new.
 
Last edited:
If you do the enginge will get "wet" on the outside with oil seeping out here and there. It might also not run as smooth as mechanical tolerances etc match the characteristics of the oil specified for the engine (I have been told).

I tried for a few years albeit with a pair of KAD 43 and they became very oily on the outside, it did however stop completely when changing to mineral and after the 2nd oilchanges.
 
You won't be short of opinions on this subject!
In my view it doesn't matter whether you do or don't use fully synth oil. I used fully synth Mobil 1 10-60 with zx1 additive in my Ford Sabres (300hp each) and they ran faultlessly up to and beyond 12000 hours - yes, 12000 hours. No - they didn't start leaking oil and yes, they were lovely and smooth and sounded beautiful. That was my experience, so that's all it proves.
 
You won't be short of opinions on this subject!

One needs to understand the reasons why .
Basically fully synthetic have added esters that attack certain types of old oil seals ,found in older diesel engines leading to leaks that's the science .

Problem is applying that nugget of info to any meaningful effect .
First what's and old engine 'the suggestion is over 30 yrs ,but its pretty ballpark and age alone not necessary an indicator if it's gots the ester softening seals .
Newer engines have none ester dissolving seals ---from when ? --
To complicate matters synthetics are thinner and have a more detergent effect cleaning up finer possiblly sludges up channels --- it's suggested in some camps therefore in a older engine ( I,am not defining what's older -you do dicide )
A change to synthetics actually may do it good from a flush ,internal clean point of view -prolonging the life via better lubrication to bearings etc ,
That's assuming it's esters have not softened the seals ,if it's got older type seals in the first place , it may not !

Hence the guy above hand clapping with 12000 hrs on Sabres -+ synthetic oil --- what year are they --so we can ponder if they fit the deffinition of "old "

Frequency of change of both oil and filter are another important variable to toss into the
" make by engines last longer " mix
 
Last edited:
One needs to understand the reasons why .
Basically fully synthetic have added esters that attack certain types of old oil seals ,found in older diesel engines leading to leaks that's the science .

Problem is applying that nugget of info to any meaningful effect .
First what's and old engine 'the suggestion is over 30 yrs ,but its pretty ballpark and age alone not necessary an indicator if it's gots the ester softening seals .
Newer engines have none ester dissolving seals ---from when ? --
To complicate matters synthetics are thinner and have a more detergent effect cleaning up finer possiblly sludges up channels --- it's suggested in some camps therefore in a older engine ( I,am not defining what's older -you do dicide )
A change to synthetics actually may do it good from a flush ,internal clean point of view -prolonging the life via better lubrication to bearings etc ,
That's assuming it's esters have not softened the seals ,if it's got older type seals in the first place , it may not !

Hence the guy above hand clapping with 12000 hrs on Sabres -+ synthetic oil --- what year are they --so we can ponder if they fit the deffinition of "old "

Frequency of change of both oil and filter are another important variable to toss into the
" make by engines last longer " mix

Not hand clapping - I'm not in any pulpit on this whatsoever - just reporting my experience. My engines were built in 1982.
 
Hi
Have just gone back to SAE 30 oil as my Sabres were smoking badly , the change is dramatic!
Was advised to do this by an engineer who had been servicing engines for many years
 
Top