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Oil and filters now or when I return to the boat


Theo

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I would suggest that if you regularly change both oil and filters (so that they are always in good condition) it will not significantly matter.

 

However, having said that the best advice is to change them before.

 

I'm leaving mine until new year when I'm back onboard.

 

Rog

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Before low sulphur diesel became mandatory I would say change it now so you get rid of the sulphuric acid that got into the oil from piston blow by.

 

These days I am with Dogless because of the very much reduced sulphur in the fuel and thus sulphuric acid in the oil. As most of us still use per low sulphur grades or lube oil there should b plenty of anti-corrosion additive available to negate any acid that is produced.

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Before low sulphur diesel became mandatory I would say change it now so you get rid of the sulphuric acid that got into the oil from piston blow by.

 

These days I am with Dogless because of the very much reduced sulphur in the fuel and thus sulphuric acid in the oil. As most of us still use per low sulphur grades or lube oil there should b plenty of anti-corrosion additive available to negate any acid that is produced.

Tony, you don't know how proud I am with your endorsement :)

 

Hope you don't mind if I tell a few friends........well everybody actually.

 

I am not a hands on, practical type, so your words cheered me no end.

 

Rog

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Before low sulphur diesel became mandatory I would say change it now so you get rid of the sulphuric acid that got into the oil from piston blow by.

 

These days I am with Dogless because of the very much reduced sulphur in the fuel and thus sulphuric acid in the oil. As most of us still use per low sulphur grades or lube oil there should b plenty of anti-corrosion additive available to negate any acid that is produced.

 

Interesting, I had never really thought about the connection between fuel sulphur content and acidic oil. What about nitric acids from the NOx, can we assume these are much lower than the Sulphuric acid? Any thoughts?

 

................Dave

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Interesting, I had never really thought about the connection between fuel sulphur content and acidic oil. What about nitric acids from the NOx, can we assume these are much lower than the Sulphuric acid? Any thoughts?

 

................Dave

 

No, it was always sulphuric acid that was talked of so like you I never considered the NOx. However the acid load in old oil must be considerably lower now.

 

I would love an oil expert to come and give us some reliable data on acids in oil and the nitric acid in particular.

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No, it was always sulphuric acid that was talked of so like you I never considered the NOx. However the acid load in old oil must be considerably lower now.

 

I would love an oil expert to come and give us some reliable data on acids in oil and the nitric acid in particular.

 

I have just done a quick bit of www research. The www is a great source of knowledge but also a great source of repeated mis information so care is needed.

Sulphuric acid from fuel dilution/blowby is mentioned quite a bit, but on balance it looks like oxidation of the oil itself, especially at high temperatures, causes it to form caboxylic acid directly from its own molecules.

So looks like its back to changing the oil at the end of the season?

 

................Dave

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I was always in the change the oil at end of season camp, to reduce corrosion from acidic elements left in an unused engine. It was pointed out though that changing at beginning of season takes with it all the condensation that has acrrued over the winter, such that running engine doesn't suffer with emulsification from such.

 

In the event and with a 450 hour oil change period, I just change when necessary now.

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I go for a 200 hour interval. "Officially" its 250 but it always needs doing when I am not in the mood so I go for 200 hours and it usually gets done at about 220. We do about 1200 hours each year so the oil changes are every other month so no worries about end of season vs start of season for me.

 

..............Dave

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I have just done a quick bit of www research. The www is a great source of knowledge but also a great source of repeated mis information so care is needed.

Sulphuric acid from fuel dilution/blowby is mentioned quite a bit, but on balance it looks like oxidation of the oil itself, especially at high temperatures, causes it to form caboxylic acid directly from its own molecules.

So looks like its back to changing the oil at the end of the season?

 

................Dave

 

That's interesting but it suggests that with very low running hours it may be fine to leave the oil.

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That's interesting but it suggests that with very low running hours it may be fine to leave the oil.

 

The graph in this link does suggest that acidity actually falls during the oils lifetime and then only increases right at the end when the "anti-acid" additive is used up.

 

http://www.kewengineering.co.uk/Auto_oils/oil_degradation.htm

 

Not sure I am 100% convinced by some of the things in this website though.

 

..............Dave

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I am not sure I am convinced either - especially in view of the disclaimer right at the top of the text on their home page.

 

That graph suggests new oil is acidic in nature and I find it difficult to believe that. If it was it must be due to other additives for other duties and thats eems plain daft to use an additive that will be rendered less effective by interaction with another.

 

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Interesting - I have just purchased a new diesel powered car, was about to take up the 5 year service plan - when the 'salesperson' said 'don't bother and annual service is not needed have it serviced every 2 years........'. Save yourself £800. - assuming a reasonable annual mileage. (Recommended oil Shell Helix)

 

Bearing in mind the service intervals on some 'Beamers', worked out and advised by 'on board' computers this advice seems reasonable.

 

Yet we seem to stick with very short service intervals on boats....... do modern oils need that much changing?.

 

I must confess mine engine uses an Sae30 oil which gets changed as recommended...........

 

But I often wonder if you only do a low number of hours on a boat engine, is an oil change needed?.......... bearing in mind getting every last drop of oil out of a sump is difficult.

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I can see now reason why it would be worse to do it now, but also expect it will be totally fine either way.

 

My 16yo bmw is serviced when it asks for it, which works out to be about annually on about 10k a year. I have second hand experience of terminal engine failure due to sludging of oil with a new engine where oil changes where carried out amd thw required (extended) intervals, using with spec oil (if not of 'recommended' brand) which does not inspire confidence.

 

 

Daniel

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Interesting - I have just purchased a new diesel powered car, was about to take up the 5 year service plan - when the 'salesperson' said 'don't bother and annual service is not needed have it serviced every 2 years........'. Save yourself £800. - assuming a reasonable annual mileage. (Recommended oil Shell Helix)

 

Bearing in mind the service intervals on some 'Beamers', worked out and advised by 'on board' computers this advice seems reasonable.

 

Yet we seem to stick with very short service intervals on boats....... do modern oils need that much changing?

In response to your first 3 points (above):

 

I'd advise you to do your own maths on the BMW Service Inclusive Pack as it's usually quite a significant saving over pay as you go. Frankly, many BMW sales persons don't know their product as well as you'd hope. My latest 5 series surprised me with headlights which steer the full beam around other traffic - when I pointed this out to the experienced salesman you'd have thought I'd said it can hover.

 

BMW insist on fully synthetic BMW approved long-life oil to achieve their indicated or 2 year (whichever is first) change interval. I was surprised to discover on their website the other day that Beta Marine now seem happy for their engines to use semi-synthetic, but many Narrowboat engine suppliers insist on mineral oil only. Not sure any say anything other than don't use fully synthetic.

 

As above, most narrowboats don't use 'modern' oils - see plenty of debate on here about API-CC oils and whether the later spec oils are suitable.

 

 

 

 

Edited to add that I appear to have jumped to the conclusion that your new car is a BMW because you go on to mention them. Disregard para 1 if it's not!

Edited by Sea Dog
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In response to your first 3 points (above):

 

I'd advise you to do your own maths on the BMW Service Inclusive Pack as it's usually quite a significant saving over pay as you go. Frankly, many BMW sales persons don't know their product as well as you'd hope. My latest 5 series surprised me with headlights which steer the full beam around other traffic - when I pointed this out to the experienced salesman you'd have thought I'd said it can hover.

 

BMW insist on fully synthetic BMW approved long-life oil to achieve their indicated or 2 year (whichever is first) change interval. I was surprised to discover on their website the other day that Beta Marine now seem happy for their engines to use semi-synthetic, but many Narrowboat engine suppliers insist on mineral oil only. Not sure any say anything other than don't use fully synthetic.

 

As above, most narrowboats don't use 'modern' oils - see plenty of debate on here about API-CC oils and whether the later spec oils are suitable.

 

 

 

 

Edited to add that I appear to have jumped to the conclusion that your new car is a BMW because you go on to mention them. Disregard para 1 if it's not!

 

Fair enough - for BMW's - I can only quote what friends who own them say - I purchased a Hyundai (to replace another) and the annual service is geared to 2 year intervals with optional basic inspections on a annual basis, this car has lights which steers round corners as well.

 

I agree about comments on synthetic oils for Nb. engines - but do we change the oil too often?......... I have watched and taken part in the debate about modern oils and engines / older engines (I have a Gardner) so Sae 30 is the only oil to use, but for modern diesel engines - if a car can do 20,000 miles without an oil change why do boat engines need it changing so frequently?.

 

L.

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Fair enough - for BMW's - I can only quote what friends who own them say - I purchased a Hyundai (to replace another) and the annual service is geared to 2 year intervals with optional basic inspections on a annual basis, this car has lights which steers round corners as well.

 

I agree about comments on synthetic oils for Nb. engines - but do we change the oil too often?......... I have watched and taken part in the debate about modern oils and engines / older engines (I have a Gardner) so Sae 30 is the only oil to use, but for modern diesel engines - if a car can do 20,000 miles without an oil change why do boat engines need it changing so frequently?.

 

L.

 

Not an expert, but I suspect:....

Boat engines are generally expected to do at least 10,000 hours without any trouble, that's equivalent to 400,000 miles at 40mph in a car and most car engines never need to last that long. Also the automotive marketing men push the engineers to accept a long service interval because modern motorists dislike services. Long life is more important than infrequent servicing for boat and industrial engine.

I expect a boat engine would probably do ok on long service intervals, do you want to risk it?

The extensive light load running is also not ideal for diesel engines, though in their original industrial applications the service intervals are generally similar.

 

................Dave

 

................Dave

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