Best oil for BMC 1500?

[jhodgski]

Can anyone recommend? (Got an oil-change well overdue...)

 

 

Cheers,

James

[onthecut]

Hi James.

 

Either a straight 30 Diesel or a low spec multigrade not above 'CC' rating. Don't forget to make sure the filter bowl is properly seated when you restart.

 

Mike.

[David Schweizer]

Can anyone recommend? (Got an oil-change well overdue...)

Cheers,

James

I use Morris Supreme 30 which is a straight SAE 30 grade API SD/CC oil. Some people prefer Magnol 20/50 which is a multi grade, but either way do not use anything with a higher rating than SF/CD as it will contain aditives designed for faster running, higher load engines which could cause bore glazing and smoking on an older design engine.

 

Morris oil can be obtained in most chandleries but it is much cheaper to buy it direct, particularly if you have the space for a 25litre can as the delivery is free. Morris have a website, which is a bit difficult to navigate here is the sales page, Supreme 30 can be found in eitherv the Vintage or marine sections.

 

http://www.morrislubricantsonline.co.uk/

 

Another hint, try and source your filters through an Agricultural Merchant. I get mine for £2.70 each, although these days I have to order them as the old Leyland tractor, which uses the same filters as the BMC 1.5, is becoming a bit less common than it used to be.

[jhodgski]

Cheers guys - just ordered 25L of Morris Supreme 30.

 

May be a daft question, but will it have an expiry date as I'm not sure how long it will take me to get through 25L??

 

Cheers,

James

 

And re the filters, I just bought a new diesel filter recently for £2 from our local auto spares shops - but the local marina is selling them for £8!...

[Serendipity]

Cheers guys - just ordered 25L of Morris Supreme 30.

 

May be a daft question, but will it have an expiry date as I'm not sure how long it will take me to get through 25L??

 

You can never have too many oil changes

[Timleech]

I use Morris Supreme 30 which is a straight SAE 30 grade API SD/CC oil. Some people prefer Magnol 20/50 which is a multi grade, but either way do not use anything with a higher rating than SF/CD as it will contain aditives designed for faster running, higher load engines which could cause bore glazing and smoking on an older design engine.

 

Please be a bit careful talking about 'straight' oils. Strictly these are oils with no or minimal additives (no detergency). I know of one person who was advised to use a straight oil in their RN, and they did so. The result was predictably an engine full of sludge.

 

Tim

[Serendipity]

Please be a bit careful talking about 'straight' oils. Strictly these are oils with no or minimal additives (no detergency). I know of one person who was advised to use a straight oil in their RN, and they did so. The result was predictably an engine full of sludge.

 

Tim

 

Good point, but again a change at between 50-100 hours helps with this. I too use Morris 30 in my BMC and try never to go over 110.

 

Edited to say - and if you're really concerned about that, every other change, use a can of flush which you add to the hot oil to thin it and loosen any sludge before changing it. (I suspect you're paying 3 quid for no more than a can of diesel with this stuff - anyone know the formulation?)

Edited December 18, 2007 by Serendipity

[Timleech]

Good point, but again a change at between 50-100 hours helps with this. I too use Morris 30 in my BMC and try never to go over 110.

 

 

The point I meant to make is that Morris Supreme 30 isn't a straight oil, it's a Monograde oil which is something different

 

Tim

Edited December 18, 2007 by Timleech

[Supermalc]

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

 

Worth reposting - I've found this an informative page, eloquently written.

 

Not sure if this is nationwide, but Vauxhall dealer does discouted oils, that are as good as any. Their mineral diesel oil is suitable for all older diesel engines.

[jhodgski]

I spoke to Morris Lubricants Online and their tech guy recommended the Supreme 30 without a doubt for the BMC 1500.

 

I asked their sales about how often to do oil changes and he initially suggested every 300 hours. But when I told him it only does about 2 hours a week, he said every 6 months (which seems like not very long - esp. as the last oil change was about 7 years ago!... )

Edited December 18, 2007 by jhodgski

[Serendipity]

I spoke to Morris Lubricants Online and their tech guy recommended the Supreme 30 without a doubt for the BMC 1500.

 

I asked their sales about how often to do oil changes and he initially suggested every 300 hours. But when I told him it only does about 2 hours a week, he said every 6 months (which seems like not very long - esp. as the last oil change was about 7 years ago!... )

 

I've seen 50hrs quoted on the web (I remember thinking it was a seemingly reliable source, but can't recall what it was offhand). When these units were in vehicles, I think the service interval would have been every 5,000 miles. 5,000 miles at an average of 40mph = gives 125 hrs. Lots of assumptions, and different engine usage I know, but it works for me.

[David Schweizer]

The Thornycroft Workshop manual for the BMS 1.5 derived Marine Engine states that the first oil change should be at 100 hours and every 200 hours there after, as do other workshop manuals for the BMC 1.5 marine diesel. I have been doiung this, using SAE 30 oil for ten years and have not aquired any sludge yet.

 

The Russell Newbery Engine is an entirely different type of engine and no doubt requires an entirely different maintenance regime.

Edited December 18, 2007 by David Schweizer

[Timleech]

The Thornycroft Workshop manual for the BMS 1.5 derived Marine Engine states that the first oil change should be at 100 hours and every 200 hours there after, as do other workshop manuals for the BMC 1.5 marine diesel. I have been doiung this, using SAE 30 oil for ten years and have not aquired any sludge yet.

 

The Russell Newbery Engine is an entirely different type of engine and no doubt requires an entirely different maintenance regime.

 

I've obviously still failed to explain my point properly

 

Older engines designs like the BMC and the RN are happiest with, if you like, an older 'style' of oil, with a spec which was arrived at long before turbochargers became everyday items on small diesels. These 'old style' oils are denoted these days by the API CC spec. Until fairly recently, the US military 'Supplement 1' spec was used, in fact I can still by 'DS1' oil locally (Diesel Supplement 1), it's exactly the same oil as is sold by the same people as 'API CC' The older engines also tend to be better with a monograde oil (SAE 20 or SAE 30) rather than the multigrade (eg 10W/40) which are ubiquitous today.

 

This is a totally different issue from that of 'straight' oils, these are oils with no or almost no additives, especially detergents.

I don't know whether they have an API classification, but I rather doubt it.

 

The RN engine design dates from a time when 'straight' oils were commonplace, they will run OK with them but the oil needs to be changed at least twice as frequently, and great care needs to be taken if switching from a 'Straight' oil to a Detergent oil, as the detergent can loosen sludge which has collected in oilways, and deposit it in the wrong places with potentially serious consequences. API CC, CD, CF etc are all detergent oils, 'Straight' oil is not. Straight oils are best avoided unless you're running something like a Bolinder with total loss lubrication. Morris Supreme is not a straight oil.

 

I hope that's a bit clearer

 

Tim

[Yoda]

Good point, but again a change at between 50-100 hours helps with this. I too use Morris 30 in my BMC and try never to go over 110.

 

Edited to say - and if you're really concerned about that, every other change, use a can of flush which you add to the hot oil to thin it and loosen any sludge before changing it. (I suspect you're paying 3 quid for no more than a can of diesel with this stuff - anyone know the formulation?)

 

Depending on the engine, you could use kerosene as a flush or a mix of kerosene and fresh oil. The important thing is to do the job whilst the engine is hot. Change the oil filter when you put the new oil in and slightly over fill on the dipstick.

[Big Steve]

20/50 oils were readily available in the late 60's when BMC's were in there prime, so why does everyone appear not to like the stuff in older engines?

[Serendipity]

I hope that's a bit clearer ;)Tim

Thanks - yes it is

20/50 oils were readily available in the late 60's when BMC's were in there prime, so why does everyone appear not to like the stuff in older engines?

That's a good point - the Tempest manual quotes either 20/50 or (nearly said straight ) 30. Would 30 be a better option for an engine with signs of wear?

[David Schweizer]

I've obviously still failed to explain my point properly

 

Older engines designs like the BMC and the RN are happiest with, if you like, an older 'style' of oil, with a spec which was arrived at long before turbochargers became everyday items on small diesels. These 'old style' oils are denoted these days by the API CC spec. Until fairly recently, the US military 'Supplement 1' spec was used, in fact I can still by 'DS1' oil locally (Diesel Supplement 1), it's exactly the same oil as is sold by the same people as 'API CC' The older engines also tend to be better with a monograde oil (SAE 20 or SAE 30) rather than the multigrade (eg 10W/40) which are ubiquitous today.

 

This is a totally different issue from that of 'straight' oils, these are oils with no or almost no additives, especially detergents.

I don't know whether they have an API classification, but I rather doubt it.

 

The RN engine design dates from a time when 'straight' oils were commonplace, they will run OK with them but the oil needs to be changed at least twice as frequently, and great care needs to be taken if switching from a 'Straight' oil to a Detergent oil, as the detergent can loosen sludge which has collected in oilways, and deposit it in the wrong places with potentially serious consequences. API CC, CD, CF etc are all detergent oils, 'Straight' oil is not. Straight oils are best avoided unless you're running something like a Bolinder with total loss lubrication. Morris Supreme is not a straight oil.

 

I hope that's a bit clearer

 

Tim

It was clear the first time, I accept that I used the term straight incorrectly, instead of monograde, but I did make the point using API CC or CD, and explained why.

[Speedwell]

Thanks - yes it is :DThat's a good point - the Tempest manual quotes either 20/50 or (nearly said straight ) 30. Would 30 be a better option for an engine with signs of wear?

Absolutely not ! 20/50 means it behaves as SAE20 when cold for easier starting and SAE50 when hot for reduced oil consumption.

Arthur

[Capt.Golightly]

So would this be a safe bet for my BMC 1.5? http://www.morrislubricantsonline.co.uk/golden-film-sae-30-classic-motor-oil.html

[TNLI]

On 18/12/2007 at 17:24, David Schweizer said:

The Thornycroft Workshop manual for the BMS 1.5 derived Marine Engine states that the first oil change should be at 100 hours and every 200 hours there after, as do other workshop manuals for the BMC 1.5 marine diesel. I have been doiung this, using SAE 30 oil for ten years and have not aquired any sludge yet.

 

The Russell Newbery Engine is an entirely different type of engine and no doubt requires an entirely different maintenance regime.

 

How often you change the oil and/or filter depend on the condition of the engine and the nature of its use. In general terms, changing the oil every 100 hours and both the oil and filter every 200 hours seems like a good idea, unless the engine is in poor condition, for example the HP fuel pump seals are causing fuel contamination, or the rings are poor. Then the interval for the oil change should be reduced by half.

 

SAE 30 marine oils last slightly longer than multigrades like a 10 or 15w40, due to the fact that they do not contain viscosity inhibitor additives, which make the oil prone to high temperature shearing. They also cost less, BUT the big downside, is that if you are not in warm waters all year, they are real tough on the starter motor.

 

Changing the oil or filter too often increases wear, it does not reduce it. The reason is that the detergent additives in a good oil are a bit too active to start with and damage the Zinc based anti wear additives slightly faster than a new layer is deposited for the first 10 to 20 hours. It also relates to the fact that normal cheap oil filters are less efficient when new, rather than well used. The difference is very significant in terms of the amount of debris that gets past them.

 

There is a third factor in oil choice, which is to try and avoid cheap mineral based oils that have a high particle count when new. In other words they are already contaminated with ultra fine Silicon (sand) particles. Several big diesel manufacturers have warnings out about increased main block wear rates from the use of non major brand mineral oils, and in one case about using any oil with high levels of Moly additive included, (Corrosion related).

 

The quality of the oil filter is just as important as the actual oil, so buy the best you can afford. I tend to look at what ASAP or Mann list.

 

Finally it's bad news to leave an oil change longer than a year, as old oil is slightly corrosive, and about half of all main block wear does not result from direct engine on wear issues, it results from the effects of corrosion that occurs after shut down. Good oil do include additives to try and reduce that issue.

 

PS: By major brand I mean, Liqui Moly, Castrol, BP and Shell, plus any manufacturer specific oils like the ones made by Morris oils. Also those companies do have very good oil finder pages on their web sites, although it is essential to double check the API/Acea specification and any user manual guide as regards viscosity choices.

 

I presently use Mobil Delvac 10w40 EXP, BUT the summer and winter oil change game is better in engine wear terms. So a 5w30 in winter, and a SAE 30 or 40 in summer.  Whether an oil says marine on the can does not really matter, BUT I would tend to try and use a diesel only oil if possible, as they contain higher detergent additive levels that can be very important in terms of sludge prevention in older diesels.

 

PPS: The Morris lubricants Golden Arrow single grade oils are interesting, but the comments about reduced additive (Low ash and low TBN) oils are kind of iffy in terms of bore glazing caused by low power use. If you use an oil with less detergent additives, it can easily result in sludge and varnish formation if the oil is not changed often enough. In reality you are swapping one problem for another. The answer is to rev up or use max continous power before shutting down. Using low power settings is the root cause of no end of trouble in an older diesels. More modern diesels with common rail injection systems are far better in that respect, as are diesel electric drive systems.

Edited September 18, 2021 by TNLI

[TNLI]

On 19/12/2007 at 21:12, David Schweizer said:

It was clear the first time, I accept that I used the term straight incorrectly, instead of monograde, but I did make the point using API CC or CD, and explained why.

 

Good post that one, and I must admit I have used the term straight oil a few times, when what I meant was a single grade oil. The comment about detergents is very true if you have a sludge monster or forget to change the oil often enough. TBN (Total Base Number) is a good way of figuring out how well an oil will help clean the block. The TBN of the oil I use (Delvac 10w40) is 15, the TBN of the Morris oil is only 6. Most diesels oil have a TBN of around 10, so the Morris oil is nothing special in cleaning terms.

[BEngo]

Horses for courses.  The BMC and other engines are fine on a detergent mineral oil provided they have a filter to clear out the cr@p that the detergent holds in the oil.  Something like an Austin 7 ( ok itis  petrol but...aaàà)or a Kelvin J,K or L is an entirely different kettle of potatoes.  These engines all use spit and pray lubrication, have minimal filtration (a gauze strainer only) and definitely do not want the muck to circulate with the oil because that just causes extra wear.   They need a low detergent monograde mineral oil.  This allows the carbon, wear products etc. to deposit themselves as sludge in the sump. The oil change interval is pretty short and the sump needs a good scrape out fairly frequently, but oil is still cheaper than engine rebuilding.

 

N

[MtB]

1 hour ago, BEngo said:

Horses for courses.  The BMC and other engines are fine on a detergent mineral oil provided they have a filter to clear out the cr@p that the detergent holds in the oil.  Something like an Austin 7 ( ok itis  petrol but...aaàà)or a Kelvin J,K or L is an entirely different kettle of potatoes.  These engines all use spit and pray lubrication, have minimal filtration (a gauze strainer only) and definitely do not want the muck to circulate with the oil because that just causes extra wear.   They need a low detergent monograde mineral oil.  This allows the carbon, wear products etc. to deposit themselves as sludge in the sump. The oil change interval is pretty short and the sump needs a good scrape out fairly frequently, but oil is still cheaper than engine rebuilding.

 

N

 

So just to clarify, please, Morris SAE30 monograde is a good example of such an oil? 

 

I need to change the oil on both my Kelvins and it's what I've always used before, but always had some doubts. 

[Troyboy]

11 hours ago, TNLI said:

 

How often you change the oil and/or filter depend on the condition of the engine and the nature of its use. In general terms, changing the oil every 100 hours and both the oil and filter every 200 hours seems like a good idea, unless the engine is in poor condition, for example the HP fuel pump seals are causing fuel contamination, or the rings are poor. Then the interval for the oil change should be reduced by half.

 

SAE 30 marine oils last slightly longer than multigrades like a 10 or 15w40, due to the fact that they do not contain viscosity inhibitor additives, which make the oil prone to high temperature shearing. They also cost less, BUT the big downside, is that if you are not in warm waters all year, they are real tough on the starter motor.

 

Changing the oil or filter too often increases wear, it does not reduce it. The reason is that the detergent additives in a good oil are a bit too active to start with and damage the Zinc based anti wear additives slightly faster than a new layer is deposited for the first 10 to 20 hours. It also relates to the fact that normal cheap oil filters are less efficient when new, rather than well used. The difference is very significant in terms of the amount of debris that gets past them.

 

There is a third factor in oil choice, which is to try and avoid cheap mineral based oils that have a high particle count when new. In other words they are already contaminated with ultra fine Silicon (sand) particles. Several big diesel manufacturers have warnings out about increased main block wear rates from the use of non major brand mineral oils, and in one case about using any oil with high levels of Moly additive included, (Corrosion related).

 

The quality of the oil filter is just as important as the actual oil, so buy the best you can afford. I tend to look at what ASAP or Mann list.

 

Finally it's bad news to leave an oil change longer than a year, as old oil is slightly corrosive, and about half of all main block wear does not result from direct engine on wear issues, it results from the effects of corrosion that occurs after shut down. Good oil do include additives to try and reduce that issue.

 

PS: By major brand I mean, Liqui Moly, Castrol, BP and Shell, plus any manufacturer specific oils like the ones made by Morris oils. Also those companies do have very good oil finder pages on their web sites, although it is essential to double check the API/Acea specification and any user manual guide as regards viscosity choices.

 

I presently use Mobil Delvac 10w40 EXP, BUT the summer and winter oil change game is better in engine wear terms. So a 5w30 in winter, and a SAE 30 or 40 in summer.  Whether an oil says marine on the can does not really matter, BUT I would tend to try and use a diesel only oil if possible, as they contain higher detergent additive levels that can be very important in terms of sludge prevention in older diesels.

 

PPS: The Morris lubricants Golden Arrow single grade oils are interesting, but the comments about reduced additive (Low ash and low TBN) oils are kind of iffy in terms of bore glazing caused by low power use. If you use an oil with less detergent additives, it can easily result in sludge and varnish formation if the oil is not changed often enough. In reality you are swapping one problem for another. The answer is to rev up or use max continous power before shutting down. Using low power settings is the root cause of no end of trouble in an older diesels. More modern diesels with common rail injection systems are far better in that respect, as are diesel electric drive systems.

This is the first time I have ever read that changing oil and filters too often increases wear and that old filters are more efficient than new ones. I'm no expert but in 1971 British Leyland were recommending oil changes for the 1.5 diesel engine in their vehicles every 3,000 miles - 5,000 km or 3 monthly intervals . Oil filters they recommended changing every 6,000 miles -10,000km or 6 monthly intervals. 

[TNLI]

Most of the real old engines that only had a screen filter and not a real oil filter, benefit from a short oil change interval, AND the use of a flush additive just before the oil is changed, or a simple rinse out with diesel after it has been drained. Some of the screen filters are like those in some manual gearboxes, as they are magnetic and need to be cleaned. If you use a high detergent oil and forgot to clean the block out last time, it can restrict the oil flow through the filter screen, or the screen on the intake to the oil pump.