Oil Question

I was looking at this a few days ago, and found that some of the oil companies - Q8 in this particular instance - produce marine engine lubrication oil to the API CD standard. Anyone know if that's any good, and possibly more suitable than road vehicle oil?

Stuff like this: http://pds.q8research.com/pdfsheet.php?id=1056 (there are many other choices, a lot of them seem to be API CD)
 
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Be guided by the engine /gearbox manufacturer and choose oil by the API or MIL spec from any manufacturer then you shouldn't have any problems

However be careful with ATF as the latest Dexron spec may be unsuitable. The older Dexron II or Dexron III may be more suitable.
 
I was looking at this a few days ago, and found that some of the oil companies - Q8 in this particular instance - produce marine engine lubrication oil to the API CD standard. Anyone know if that's any good, and possibly more suitable than road vehicle oil?

Stuff like this: http://pds.q8research.com/pdfsheet.php?id=1056 (there are many other choices, a lot of them seem to be API CD)

Nothing wrong with Q8, they produce quality products. Suggest you read the oil for your engine page on my website, then select an API CD oil with the lowest TBN you can. I would select a multigrade rather than a monograde, 15w/40 probably best for UK climate, no lower anywhere.
 
the CD specification is quite low. Go for the highest spec you can, as the higher the spec the better the pH control, specially as diesels produce more acid radicals than petrol engines, and this causes more wear and tear and means that you have to change the oil more frequently. Second consideration is the viscosity range, covering max and min at different temperatures. Dont be fooled by so called diesel oils. The same spec oil may last longer in a petrol engine than a diesel, because petrol engine produce less pollutants, so that the same oil may have a K specification for petrol engines and a H for diesel, but it is the same oil! Also bear in mind that marine diesel run at more even temperatures and at more constant speed as compared to automotive engines, which means that they produce less pollutants between oil changes
 
I have read somewhere that the CD rating is now obsolete and that CF-4 can be used as a replacement. I've not been able to find CD rated oils anywhere.

Please note I am not an expert! /forums/images/graemlins/shocked.gif

Silly me. I should have looked at your link first.

CF -4 is the replacement for CD which is now almost unobtainable. Make sure it is mineral oil and not semi synthetic.
 
the CD specification is quite low. Go for the highest spec you can, as the higher the spec the better the pH control, specially as diesels produce more acid radicals than petrol engines, and this causes more wear and tear and means that you have to change the oil more frequently.

Sorry to disagree. There are two principal sources of acidity in engine oils - sulphur in the fuel, and to a lesser extent in the oil, and high temperatures. Now that sulphur levels in EU fuels are down to low ppm figures the TBN of most oils has been reduced accordingly.
Very few yacht engines will ever see the prolonged high temperatures that modern oils are designed to cope with, such as all-day motorway travel or extended truck use (when I was marginally involved in oil development we used to monitor trucks that travelled almost non-stop Holland to Italy and back, 24 hours per day).
Raw water cooled engines are never going to come anywhere near these temperatures and the vast majority of indirectly cooled ones are mostly used to drive the boat out of the marina and back in, and not used in between. It takes about an hour to get any small engine up to its constant running temperature.
High TBN oils will never achieve neutrality in these engines. Wear can result from continued running with basic oils, as the unused additive can form hard compounds on the piston, leading to excessive bore wear. Yanmar continued to recommend API CD for years after it was obsolete, for good reason. The low TBN of this oil was comfortably capable of coping with the small levels of sulphur in it, whereas modern oils have a far higher sulphur content (as ZDTP) to help them cope with the demands of high-lift cams and followers.
Over and above that, there is plenty of evidence on the Internet that using modern lubricants with large additive packages causes a myriad of problems in older engines. You can read more on my website.
 
Thanks for the replies all. I checked with the Lombardini dealer and enhanced mineral 15W/40 is the right stuff (no semi or fully synthetics though). Sump capacity is about 1.5L.

Just in case anyone else googles this in a few years time!
 
Thanks for the replies all. I checked with the Lombardini dealer and enhanced mineral 15W/40 is the right stuff (no semi or fully synthetics though). Sump capacity is about 1.5L.

Just in case anyone else googles this in a few years time!

That tells you very little. Just the viscosity. Just take a look at vyv cox reply and take note.

Volvo recommends an oil which is totally unsuitable to their older engines.
 
It would be appreciated if Vyv or anyone else post a link to a multigrade CD source that is still available in the UK? We should have a permanent thread for updating this info.
 

No, that one is CF. API CF/CF-4 is readilly available at good prices and is what I have been using. The "Exol Victory" seems to be the only API CD multigrade that I could find available in UK, has anyone tried it (they do a 20-50 also)? The ones in Vyvs article do not seem to be available anywhere. Which is why I was asking for links specifically for API CD.

Exol oils:
http://www.exol-lubricants.com/automotive/products/?CID=13
 
No, that one is CF. API CF/CF-4 is readilly available at good prices and is what I have been using. The "Exol Victory" seems to be the only API CD multigrade that I could find available in UK, has anyone tried it (they do a 20-50 also)? The ones in Vyvs article do not seem to be available anywhere. Which is why I was asking for links specifically for API CD.

Exol oils:
http://www.exol-lubricants.com/automotive/products/?CID=13

Your right: it is only CF and not CF-4 so suitable only for Petrol I think.....
 
The ones in Vyvs article do not seem to be available anywhere. Which is why I was asking for links specifically for API CD.

It's a while since I checked the links I gave in the article, which is a few years old now. I will try to update but I don't hold out much hope. Morris Oils make API CC, widely used by canal boats but they didn't seem interested in producing a CD. I'll try them again.
 
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