CSL in Mille Miglia or 1000 miles in one day

pmansson

pmansson

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My CSL got a good beating on Thursday as I drove it from southern Switzerland to my summerhouse in southern Sweden. It´s not normally a 1000 mile drive but with a detour in Germany to collect a gearbox it totalled just that.

The only issue was a falling oil pressure, (I have a separate gauge), after the first 600 miles. It came down to 1 bar, and I stopped at a gas station along the Autobahn to add a bottle of 5-20W oil. This brought it up to 2 when driving. The oil pump needs replacing, and as we do this we will check the conrod and crankshaft bearings to determine their condition and possible damage.

BUT, the culprit here is surely the synthetic 10-60 oil, which after 10 hours lost some of its vital properties. An expert on these cars has just told me that these M30 engines should run on SAE 10-40W or 20-50W mineral oil, unless the engine has been rebuilt with modern equipment and parts. (It is my normally very capable mechanic in Switzerland who insists on the 10-60 oil´s superiority. We will debate this next time I see him !

The triple Weber 45s also need to be dismanteled and cleaned, as the engine won´t run really well below 4,000 RPM which with my 3,64 and Getrag o/d box is about 95 MPH. This speed is certainly doable on some parts of the Autobahn and on empty roads at night in Denmark and Sweden.

I arrived at 4 AM in my summerhouse and had a well deserved sandwich, beer and shot of aqvavit, before going to bed. The very loud s/s exhaust system added to the experience !! No music, no phonecalls, comfortable Scheel seats, shotgut style earmuffs part of the time etc etc.

(The next night I did another 350 miles, arriving with the car in Stockholm at 1 AM).
 
My CSL got a good beating on Thursday as I drove it from southern Switzerland to my summerhouse in southern Sweden. It´s not normally a 1000 mile drive but with a detour in Germany to collect a gearbox it totalled just that.

The only issue was a falling oil pressure, (I have a separate gauge), after the first 600 miles. It came down to 1 bar, and I stopped at a gas station along the Autobahn to add a bottle of 5-20W oil. This brought it up to 2 when driving. The oil pump needs replacing, and as we do this we will check the conrod and crankshaft bearings to determine their condition and possible damage.

BUT, the culprit here is surely the synthetic 10-60 oil, which after 10 hours lost some of its vital properties. An expert on these cars has just told me that these M30 engines should run on SAE 10-40W or 20-50W mineral oil, unless the engine has been rebuilt with modern equipment and parts. (It is my normally very capable mechanic in Switzerland who insists on the 10-60 oil´s superiority. We will debate this next time I see him !

The triple Weber 45s also need to be dismanteled and cleaned, as the engine won´t run really well below 4,000 RPM which with my 3,64 and Getrag o/d box is about 95 MPH. This speed is certainly doable on some parts of the Autobahn and on empty roads at night in Denmark and Sweden.

I arrived at 4 AM in my summerhouse and had a well deserved sandwich, beer and shot of aqvavit, before going to bed. The very loud s/s exhaust system added to the experience !! No music, no phonecalls, comfortable Scheel seats, shotgut style earmuffs part of the time etc etc.

(The next night I did another 350 miles, arriving with the car in Stockholm at 1 AM).
 
Oil pressure in an M-30

From the get-go my mechanics have conistently recommended use of a quality 20-50 mineral based engine oil (many good choices still available here) for our climate and have observed that guidance in all the early BMW's that have passed through my hands.

A few years back--for a period of 3-4 years I did use 15-50 Mobil 1 in a mature 3.5L motor (read higher mileage) without incident of dripping or any measurable difference in consumption.

Bottom line--i believe the use of mineral based motor oil in an M-30 with change of both filter and oil at around 3,000 miles or 5,000 Km to be a very sound practice.
 
Oil pressure in an M-30

From the get-go my mechanics have conistently recommended use of a quality 20-50 mineral based engine oil (many good choices still available here) for our climate and have observed that guidance in all the early BMW's that have passed through my hands.

A few years back--for a period of 3-4 years I did use 15-50 Mobil 1 in a mature 3.5L motor (read higher mileage) without incident of dripping or any measurable difference in consumption.

Bottom line--i believe the use of mineral based motor oil in an M-30 with change of both filter and oil at around 3,000 miles or 5,000 Km to be a very sound practice.
 
pmansson said:
BUT, the culprit here is surely the synthetic 10-60 oil, which after 10 hours lost some of its vital properties. An expert on these cars has just told me that these M30 engines should run on SAE 10-40W or 20-50W mineral oil, unless the engine has been rebuilt with modern equipment and parts. (It is my normally very capable mechanic in Switzerland who insists on the 10-60 oil´s superiority. We will debate this next time I see him !
Click to expand...

This is indeed an interesting topic - one that people tend to think 'religiously' about. Personally I would never use a synthetic oil on an old/older engine and I have always run traditional mineral oils on my old cars.

Recently I switched to Castrol Classic XL 20W/50 on the CSL and have had no issues with it.
 
pmansson said:
BUT, the culprit here is surely the synthetic 10-60 oil, which after 10 hours lost some of its vital properties. An expert on these cars has just told me that these M30 engines should run on SAE 10-40W or 20-50W mineral oil, unless the engine has been rebuilt with modern equipment and parts. (It is my normally very capable mechanic in Switzerland who insists on the 10-60 oil´s superiority. We will debate this next time I see him !
Click to expand...

This is indeed an interesting topic - one that people tend to think 'religiously' about. Personally I would never use a synthetic oil on an old/older engine and I have always run traditional mineral oils on my old cars.

Recently I switched to Castrol Classic XL 20W/50 on the CSL and have had no issues with it.
 
It's actually getting harder to find 20/50 where I live
Filter and oil change every 5000miles or every 6 months is going to cover most of the situations "we" are in
 
It's actually getting harder to find 20/50 where I live
Filter and oil change every 5000miles or every 6 months is going to cover most of the situations "we" are in
 
I am not sure on this topic - I think using old technology just because the patient is old doesnt make sense - admittedly tolerances that the new oils are designed to lubricate are smaller but I am sure they are superior to the old mineral oils??? I know I feel happier with them in the car especially when they sit for a while as I think they are less prone to breakdown from the combustion acids.

I am no expert and this is purely my feeling/theory based on what i have read/heard.

Overall the frequency of changes and the driver being sympathetic - such as driving gently when cold etc will have more of an effect.
 
I am not sure on this topic - I think using old technology just because the patient is old doesnt make sense - admittedly tolerances that the new oils are designed to lubricate are smaller but I am sure they are superior to the old mineral oils??? I know I feel happier with them in the car especially when they sit for a while as I think they are less prone to breakdown from the combustion acids.

I am no expert and this is purely my feeling/theory based on what i have read/heard.

Overall the frequency of changes and the driver being sympathetic - such as driving gently when cold etc will have more of an effect.
 
pmansson said:
The only issue was a falling oil pressure, (I have a separate gauge), after the first 600 miles. It came down to 1 bar, and I stopped at a gas station along the Autobahn to add a bottle of 5-20W oil. This brought it up to 2 when driving.
. . . .
BUT, the culprit here is surely the synthetic 10-60 oil, which after 10 hours lost some of its vital properties. An expert on these cars has just told me that these M30 engines should run on SAE 10-40W or 20-50W mineral oil, unless the engine has been rebuilt with modern equipment and parts. (It is my normally very capable mechanic in Switzerland who insists on the 10-60 oil´s superiority. We will debate this next time I see him !
Click to expand...

It strikes me as odd that you would add a "5-20W" oil to your 10-60. Unless you are mistyping the numbers, 5-20W or 5W[inter]-20 dilutes/thins the oil you had in the sump. With a worn engine (greater than usual tolerances) this is likely to result is reduced oil pressure. As le BluMax noted, BMW recommended 20W-50 (this theoretically results in a 20 weight oil when the engine is kalt and a 50 weight oil when it reaches operating temperature). Unless, your ambient temperature dropped near freezing, using 5W-20 oil would not make any sense- unless that was the only oil available.

You complain that you were losing oil pressure, but if you had room for another bottle of oil, is this another way of saying you were losing oil or just low on oil? If you have leaks - low oil volume can also lead to low pressure. No matter how new or large or even tight your oil pump, if it has to pressurize good sized leaks, you will likely have low pressure. Bottom line: if you want to increase your oil pressure, running thinner than recommended oil is NOT indicated. If you have a marginally worn engine, it might benefit you to supplement your oil with a viscosity index improver such as STP or the like. Straight 40-50-or even 60 weight oil may be another alternative (if you were driving nearer the equator or as a stopgap measure for an extremely worn engine).

Observations regarding synthetic oil: I had been slow to convert to synthetic oil, having stockpiled several cases of the conventional product. If your engine leaks/burns oil as fast as you replenish it or if the engine is so worn as to dilute the oil within a few turns - synthetic oil is a waste of money. If you have an engine with much life remaining, given the choice, synthetic makes more sense.

Anecdotally, I ran an M-30 engine for several years on 20W-50 Castrol or Valvoline and the engine ran fine. By happenstance, I changed the oil to AGIP synthetic 10w-50 and the normal operating temperature dropped 10-15 degrees Farenheit - without any other modifications. Same ambient temperature, humidity and sluggish/non operational fan clutch. Idle speed was slightly higher. All of this suggests to me similarly graded synthetic oil offered less friction than the oil it replaced. It is of course possible I would have experienced the same results with any fresh oil change, but I am not so sure, having tried this with another non-BMW car.

Thinner oil reduces friction losses and this is one of the means car manufacturers use to achieve better fuel economy. Thinner weight conventional oils might achieve similar friction losses, but it is my understanding they are far less stable than synthetics over time and far less tolerant of harsher conditions (heat) then synthetics. Conventional oils are said to be less slippery than synthetics. Historically there were two reasons to avoid using synthetic oil - engine seal incompatibility and cost. Now, cost remains the primary consideration. Given the higher costs of parts and labor, the relative expense of synthetic oil seems less of a reason to avoid using it.

I would venture a guess that your mechanic is using pretty good oil if it truly has 10W-60 capabilities. I am not aware of any conventional oil with those advertised qualities and therefore assume it is synthetic. I question the need for oil that can thicken as much as 60 weight, but as another poster suggested, it is not illogical that an old patient could benefit from newer therapy or medicine. The same argument might be made regarding newer tire tread designs and rubber compounds or even unleaded fuels. FWIW, my first Coupe had inner tube equipped Michelin tires and I doubt there are many who still use them!

Consider Ferrari, Porsche and Corvette all use synthetic oils from the factory. At the very least, this suggests there are benefits worth exploring for use in the M30 engines.

viel Glueck!
 
pmansson said:
The only issue was a falling oil pressure, (I have a separate gauge), after the first 600 miles. It came down to 1 bar, and I stopped at a gas station along the Autobahn to add a bottle of 5-20W oil. This brought it up to 2 when driving.
. . . .
BUT, the culprit here is surely the synthetic 10-60 oil, which after 10 hours lost some of its vital properties. An expert on these cars has just told me that these M30 engines should run on SAE 10-40W or 20-50W mineral oil, unless the engine has been rebuilt with modern equipment and parts. (It is my normally very capable mechanic in Switzerland who insists on the 10-60 oil´s superiority. We will debate this next time I see him !
Click to expand...

It strikes me as odd that you would add a "5-20W" oil to your 10-60. Unless you are mistyping the numbers, 5-20W or 5W[inter]-20 dilutes/thins the oil you had in the sump. With a worn engine (greater than usual tolerances) this is likely to result is reduced oil pressure. As le BluMax noted, BMW recommended 20W-50 (this theoretically results in a 20 weight oil when the engine is kalt and a 50 weight oil when it reaches operating temperature). Unless, your ambient temperature dropped near freezing, using 5W-20 oil would not make any sense- unless that was the only oil available.

You complain that you were losing oil pressure, but if you had room for another bottle of oil, is this another way of saying you were losing oil or just low on oil? If you have leaks - low oil volume can also lead to low pressure. No matter how new or large or even tight your oil pump, if it has to pressurize good sized leaks, you will likely have low pressure. Bottom line: if you want to increase your oil pressure, running thinner than recommended oil is NOT indicated. If you have a marginally worn engine, it might benefit you to supplement your oil with a viscosity index improver such as STP or the like. Straight 40-50-or even 60 weight oil may be another alternative (if you were driving nearer the equator or as a stopgap measure for an extremely worn engine).

Observations regarding synthetic oil: I had been slow to convert to synthetic oil, having stockpiled several cases of the conventional product. If your engine leaks/burns oil as fast as you replenish it or if the engine is so worn as to dilute the oil within a few turns - synthetic oil is a waste of money. If you have an engine with much life remaining, given the choice, synthetic makes more sense.

Anecdotally, I ran an M-30 engine for several years on 20W-50 Castrol or Valvoline and the engine ran fine. By happenstance, I changed the oil to AGIP synthetic 10w-50 and the normal operating temperature dropped 10-15 degrees Farenheit - without any other modifications. Same ambient temperature, humidity and sluggish/non operational fan clutch. Idle speed was slightly higher. All of this suggests to me similarly graded synthetic oil offered less friction than the oil it replaced. It is of course possible I would have experienced the same results with any fresh oil change, but I am not so sure, having tried this with another non-BMW car.

Thinner oil reduces friction losses and this is one of the means car manufacturers use to achieve better fuel economy. Thinner weight conventional oils might achieve similar friction losses, but it is my understanding they are far less stable than synthetics over time and far less tolerant of harsher conditions (heat) then synthetics. Conventional oils are said to be less slippery than synthetics. Historically there were two reasons to avoid using synthetic oil - engine seal incompatibility and cost. Now, cost remains the primary consideration. Given the higher costs of parts and labor, the relative expense of synthetic oil seems less of a reason to avoid using it.

I would venture a guess that your mechanic is using pretty good oil if it truly has 10W-60 capabilities. I am not aware of any conventional oil with those advertised qualities and therefore assume it is synthetic. I question the need for oil that can thicken as much as 60 weight, but as another poster suggested, it is not illogical that an old patient could benefit from newer therapy or medicine. The same argument might be made regarding newer tire tread designs and rubber compounds or even unleaded fuels. FWIW, my first Coupe had inner tube equipped Michelin tires and I doubt there are many who still use them!

Consider Ferrari, Porsche and Corvette all use synthetic oils from the factory. At the very least, this suggests there are benefits worth exploring for use in the M30 engines.

viel Glueck!
 
I have to agree with the pro synthetic posters here. Oil companies invest millions in developing and testing new products. Many new cars are able to go 20,000 miles or 32,000 Km in metric without an oil change (and some cars even more) and whilst I personally wouldn't leave it that long can you imagine trying that with an old technology mineral oil. Lets not forget that when our beloved Coupes were current BMW recommended that the oil was changed every 3000 miles because it lost its shear properties after a very short time.
Having said that I can't see the point in going as high as a 60W oil synthetic or otherwise, a good quality 10-40 or maybe at a push 20-50 but personally I use 10-40 semi synthetic in my own Coupe mainy if I'm honest because it's the most common oil we use at the garage and therefore we bulk buy it thus reducing the cost even further and so I can afford to change the oil every 3000 miles by which time despite driving the car hard the oil has barely started to discolor.

The thinner the oil that you use the more your friction loses are reduced thus improving both power and fuel economy, it was only the advent of semi and then fully synthetic technology which allowed the use of such thin grades whilst maintaining the oils ability to protect your engine.

pmansson with regards to your oil pressure dropping you don't say if your pressure returned to normal after the engine had cooled or wether it was still relativly low. If it returned to normal then I have to question the quality of the oil your mechanic uses as one of two things could be happening. Either the oil is losing its grade (if it is infact a 60W) or it is frothing badly and contains more than the normal ammount of air bubbles after being driven hard for a while. As a side note some modern Diesel engines use a hydraulic injection pump which utilises the engines oil pressure to inject the fuel, these engines use a special anti frothing engine oil known as "pump deuce oil" other wise they run really badly so it is possible that your problem is due to frothing.
If however your oil pressure didn't return to normal after the engine had stood over night then you have a mechanical problem due to wear and tear and you'll have to rebuild the motor but you were prepared for that any way.
 
I have to agree with the pro synthetic posters here. Oil companies invest millions in developing and testing new products. Many new cars are able to go 20,000 miles or 32,000 Km in metric without an oil change (and some cars even more) and whilst I personally wouldn't leave it that long can you imagine trying that with an old technology mineral oil. Lets not forget that when our beloved Coupes were current BMW recommended that the oil was changed every 3000 miles because it lost its shear properties after a very short time.
Having said that I can't see the point in going as high as a 60W oil synthetic or otherwise, a good quality 10-40 or maybe at a push 20-50 but personally I use 10-40 semi synthetic in my own Coupe mainy if I'm honest because it's the most common oil we use at the garage and therefore we bulk buy it thus reducing the cost even further and so I can afford to change the oil every 3000 miles by which time despite driving the car hard the oil has barely started to discolor.

The thinner the oil that you use the more your friction loses are reduced thus improving both power and fuel economy, it was only the advent of semi and then fully synthetic technology which allowed the use of such thin grades whilst maintaining the oils ability to protect your engine.

pmansson with regards to your oil pressure dropping you don't say if your pressure returned to normal after the engine had cooled or wether it was still relativly low. If it returned to normal then I have to question the quality of the oil your mechanic uses as one of two things could be happening. Either the oil is losing its grade (if it is infact a 60W) or it is frothing badly and contains more than the normal ammount of air bubbles after being driven hard for a while. As a side note some modern Diesel engines use a hydraulic injection pump which utilises the engines oil pressure to inject the fuel, these engines use a special anti frothing engine oil known as "pump deuce oil" other wise they run really badly so it is possible that your problem is due to frothing.
If however your oil pressure didn't return to normal after the engine had stood over night then you have a mechanical problem due to wear and tear and you'll have to rebuild the motor but you were prepared for that any way.
 
oil and fuel

hi, just one thing I had in my mind was the weber carb not working properly, check if the oil smells like gasoline, it can be the carbs is putting a lot of fuel in the engine and it will washes the bores, and the fuel go in the sump.
just thought,

Og kommer du kjørende via Vilnius neste gang så skal jeg tilby deg Linje akevitt:)
 
oil and fuel

hi, just one thing I had in my mind was the weber carb not working properly, check if the oil smells like gasoline, it can be the carbs is putting a lot of fuel in the engine and it will washes the bores, and the fuel go in the sump.
just thought,

Og kommer du kjørende via Vilnius neste gang så skal jeg tilby deg Linje akevitt:)
 
There was a very long thread recently on MyE28.com about oils and additives for M30 engines. Sorry I don't have a link.
 
There was a very long thread recently on MyE28.com about oils and additives for M30 engines. Sorry I don't have a link.
 
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