Which oil?

[Otter]

My apologies, I've chucked this into two or three threads as a bit of drift and I'm not quite sure I've got the answer.

Thornycroft 235, 1977 four cylinder diesel, max revs about 2400, normally aspirated. What oil should I put in it? I would really appreciate a link to an actual example, I'm a mechanical machine numpty and find it easier to follow a knowledgeable chap, click on a link and order three of them.

Cheers, Jackson.

 

[sarabande]

any, and I mean, any unsophisticated diesel engine oil will do. You don't need super detergent, synthetic, artificial stuff. Look for the cheapest source of 15 - 40 tractor engine oil for the best value.

http://www.ebay.co.uk/itm/Super-Uni...CommercialVehicleParts_SM&hash=item45f919e612

That is a universal (engine and gearbox and hydraulic oil) I use on the John Deeres (with a basic turbo).


I used to put almost any basic oil into my CW with the same engine. It's changing oil plus filter regularly that keeps the engine happy.

 

[Otter]

Thanks SB, I'll give some of that a go.

 

[Jim@sea]

I am a bit obsessive where engine oil is concerned due to starting my working life at a garage where we specialised in repairing engines.
And in those days using Flushing Oil was a normal procedure, which I have always continued with.
The boat I have just bought has Thornycroft Engine (BMC 2.5 Diesel) and I am going to use ordinary engine oil in it.
Mind you I have loads of spare Synthetic Oil so I am going to use that as Flushing Oil.
I also may use an Additive like "Wynns"
(What happened to Molyslip that seemed good at the time)

 

[Otter]

Is it overkill to go to the full 20w/50?

http://www.halfords.com/webapp/wcs/stores/servlet/product_storeId_10001_catalogId_10151_productId_166289_langId_-1_categoryId_165581

 

[Alpha22]

Is it overkill to go to the full 20w/50?

http://www.halfords.com/webapp/wcs/stores/servlet/product_storeId_10001_catalogId_10151_productId_166289_langId_-1_categoryId_165581

In the UK that would be great oil ....... if it is local and suits you, it will be absolutely fine. In the UK, straight 30 grade will be fine too!!! These engines in boats are very low stressed and would probably run fine for the next 50 years on chip fat and lard!!!

 

[superheat6k]

Is it overkill to go to the full 20w/50?

http://www.halfords.com/webapp/wcs/stores/servlet/product_storeId_10001_catalogId_10151_productId_166289_langId_-1_categoryId_165581

This simply indicates the cold or Winter viscosity. Full details of what the various numbers mean here ...

http://www.carbibles.com/engineoil_bible.html

I use Shell Rimula 15W40, no probs with it. As long as the oil is CF spec or higher then that should be fine.

 

[ditchcrawler]

In my Volvo 2003 of 1985 vintage I use the 15/40 from B and Q.Costs me about £12 but I get the pensioners 10% discount on wednesdays.

 

[theoldsalt]

In my Thornycroft T80 I also use engine oil from B&Q and have been for the last 10 years - Carlube Daytona 20W50 API CC

http://www.diy.com/nav/fix/car-main...Daytona-20W50-Motor-Oil-9217985?skuId=9227684

 

[sailorman]

Is it overkill to go to the full 20w/50?

http://www.halfords.com/webapp/wcs/..._productId_166289_langId_-1_categoryId_165581

!5>40 CF or CF4 as you use in a normally aspirated diesel car

 

[pampas]

Asda`s finest for me

 

[Hoolie]

This topic has been discussed here before and IIRC the problem with synthetic oils is their additives that need the high temperatures of a high performance engine. The average marine engine can't deal with them and the residues are harmful to the engine. Just use basic mineral oil.

 

[single]

I can't remember what spec it was (i think 10w40?) for my T95, but i had no option other than Halfords and was shocked at £50 for 5ltrs.I must admit after putting that stuff in, it stopped having the low oil pressure warning coming on after a long voyage! (it was Mobil 1)

 

[macd]

I can't remember what spec it was (i think 10w40?) for my T95, but i had no option other than Halfords and was shocked at £50 for 5ltrs.I must admit after putting that stuff in, it stopped having the low oil pressure warning coming on after a long voyage! (it was Mobil 1)

Mobil 1 is a full synthetic and not only way overspecc'd for a T95 but, as Hoolie writes, could be actually harmful long-term. Check out Vyv Cox's website for chapter and verse. He was a metallurgist for Shell and knows of what he writes.

 

[single]

Mobil 1 is a full synthetic and not only way overspecc'd for a T95 but, as Hoolie writes, could be actually harmful long-term. Check out Vyv Cox's website for chapter and verse. He was a metallurgist for Shell and knows of what he writes.

Woops, yep i think it was this http://www.halfords.com/webapp/wcs/..._productId_241643_langId_-1_categoryId_165581
You say long term damage but it gets changed each year, so thats only a few hundred engine hours. Compared to a car engine its hardly anything, so i doubt it will do any damage just this once?

 

[single]

I just did a quick search so where do i get 0w40 thats non synthetic???

 

[vyv_cox]

I just did a quick search so where do i get 0w40 thats non synthetic???

I would advise very strongly that you do not use any lubricant in a yacht engine with a viscosity as low as 0/40. The only justification for these low viscosities is fuel economy, which requires the engine to be designed with aluminium bearings, hardened crankshaft and other measures. I doubt that any yacht engines have these. I would not use anything less than 15/40 and for my elderly BMC 2.2 of similar age to the Thorneycroft in the OP question I use 20/50.

So far as the grade of oil is concerned I suggest you look at my website, kindly referenced by macd. I use API CC in the BMC, widely available, cheap and used by hundreds of narrow boats. Mine came from Morris Lubricants who will deliver. In my Yanmar GM30F I use API CD, 15/40. API CD is close to unobtainable now but API CF-4 is a reasonable substitute.

 

[single]

I would advise very strongly that you do not use any lubricant in a yacht engine with a viscosity as low as 0/40. The only justification for these low viscosities is fuel economy, which requires the engine to be designed with aluminium bearings, hardened crankshaft and other measures. I doubt that any yacht engines have these. I would not use anything less than 15/40 and for my elderly BMC 2.2 of similar age to the Thorneycroft in the OP question I use 20/50.

So far as the grade of oil is concerned I suggest you look at my website, kindly referenced by macd. I use API CC in the BMC, widely available, cheap and used by hundreds of narrow boats. Mine came from Morris Lubricants who will deliver. In my Yanmar GM30F I use API CD, 15/40. API CD is close to unobtainable now but API CF-4 is a reasonable substitute.

Interesting.I will change it but i wonder why the manual says 0w40?

 

[single]

Just found the manual.It must have been mobil 1- 10w30 i put in.
View attachment 40556

 

[Otter]

I would advise very strongly that you do not use any lubricant in a yacht engine with a viscosity as low as 0/40. The only justification for these low viscosities is fuel economy, which requires the engine to be designed with aluminium bearings, hardened crankshaft and other measures. I doubt that any yacht engines have these. I would not use anything less than 15/40 and for my elderly BMC 2.2 of similar age to the Thorneycroft in the OP question I use 20/50.

So far as the grade of oil is concerned I suggest you look at my website, kindly referenced by macd. I use API CC in the BMC, widely available, cheap and used by hundreds of narrow boats. Mine came from Morris Lubricants who will deliver. In my Yanmar GM30F I use API CD, 15/40. API CD is close to unobtainable now but API CF-4 is a reasonable substitute.

Thanks - they had 5l for £12 in B&Q yesterday, same price for the 20w/50 so I'll try that. The story on your website of the glazed engine because of the wrong oil and the constant revs is a salutory lesson.