Oil Change - Am I in Trouble?

[upthesolent]

Having just moved up to an inboard (Vetus M2 C5) I am still learning how to look after them. I did do some winterization to the engine (full diesel tank with bug inhibitor, run the engine in fresh water and then an anti-freeze mix) but I did not change the oil not knowing at that time that the pollutants can cause damage to the engine when left for a long period.

The oil was changed in early August and the engine ran for about 20 hours during our August holiday on her. OK, I now realise I've made a big mistake, but can anyone tell me how serious. The boat is out of water at a friendly boatyard so if it came to it, I can still do an oil change as I should have access to a hose so that I can maintain a water intake.

My next planned visit to the boat was not until the end of March which would mean the engine not being turned over for nigh on 7 months. I live on the southern Costa Blanca so I will have to arrange a flight over if this is as serious as I am thinking it might be. The engine is only about 3 years old and had about 75 hours running.

Thanks in anticipation.

 

[mickshep]

No worries there. Not a scientist but can't imagine there being an awfull lot of nasties in the oil after only 20hrs, My Vetus M3.10 was stood for over 7 yrs before I bought the boat, I turned her over for about 5 minutes by hand to get the oil circulating whilst not under load, changed the impeller and she started 1st turn of the key. Regards, Mike.

 

[richardabeattie]

I doubt if one winter is going to reduce your engine to scrap. But if you are that worried could you not get the yard to change the oil again? You also mention using a hose pipe to flush the engine. I am sure you know that the engine must be allowed to suck the water at its own pace rather than having it fed in under any pressure - getting that bit wrong can be very expensive! You winter in Spain and come to the UK for the summer sailing season? Wierd!

 

[upthesolent]

Encouraging so far - thanks gentlemen. I had thought about contacting the yard - they should have enough contacts - and if necessary, getting someone to do it if it worked out cheaper than a flight. Re the hose - I agree. I used a large bucket in August with the inlet hose immersed in it, the other hose merely replenishing the bucket.

A lot of people have commented as to why I do not have a boat here in Torrevieja where I live. Three reasons; berthing is very expensive here (way above my budget); there is also not very many places to go in a smaller boat (Leisure 23); and finally I do love the Solent and points east and west of it, with it's vast diversity of anchorages and harbours.

Sorry to digress. I would still welcome further views though.

Thanks.

 

[vyv_cox]

The contaminants in engine oil come from the combustion of the fuel and are mostly a mixture of weak organic acids such as naphthenic and carbonic acids. These will not do a great deal of harm in a new or nearly new oil, which has additives present to combat them. Generally organic acids will not corrode metal and no harm will result from leaving them in the engine after 20 hours of use. After much longer use the oil will become acidic when the additives have all been consumed.

What is harmful is the mixture of oxides of sulphur, resulting from burning the sulphur compounds that are always in oils and fuels, and water when the engine is started from cold. The mixture of the two forms sulphurous and sulphuric acids, which most definitely do corrode metal parts in the engine. However, running the engine until it is hot every time, and never running it for a couple of minutes only, will largely prevent the transfer of water down the bores.

So the answer to your question is that putting your engine away for the winter when it is thoroughly hot, even with oil that is not absolutely new, will ensure it remains in good condition for the longest possible time.

 

[upthesolent]

Three Nil then. Your informative post is pretty well definitive vyv.

Thanks to all!