engine oil to use

Hudsonrules

:)Good evening my friends, I have qa '37 Terraplane that has been sitiing for two or three years, started occasionaly. Now I want to change the oil and check the car over before I go very far. Question: can I use 30 weight detergent oil in this engine,(212) or should I find 30 weight non detergent? Thanks in advance and have a great week. Arnie M.

Unknown

Arnie,



If the engine has never been apart or is full of sludge, you may want to stick with non detergent.

mars55

Here is an interesting article on oils for older engines. It was written by a British oil company called Morris Lubricants.



http://www.morrislubricants.co.uk/



Lubricants for Vintage and Veteran Engines



Choosing a suitable lubricant for the four stroke engines (both petrol and diesel) found in vintage and veteran engines can be somewhat problematical to the owner. The advances, which have been made in the development and formulation of lubricants for the modern internal combustion engine, are such that the attributes of these products are not compatible with the technology employed in the older engine.



Firstly, when considering these engines, all tolerances, especially between the piston and the cylinder walls are greater than in a modern engine. Therefore, as film thickness is proportional to viscosity, a monograde SAE 30 or SAE 40 viscosity is normally specified to avoid leakage through surface seals and to form a gas tight seal between the piston rings and cylinder wall. The reason why a mongrade is called for is that in these high shear situations multigrades undergo a temporary loss in viscosity. This results in a reduction of oil film thickness and hence combustion gases can get past the piston rings (known as blowby) and there can also be seal leakage. This viscosity decrease is due to lubricant polymers that are used in multigrades to offset the mineral oils natural thinning as the temperature increases. These polymers are subject to shear. Modern engines are designed to run on much lower viscosity oils and therefore this shear effect (temporary or permanent) is not usually noticeable.



Filtration of the oil also plays an extremely important part in the selection of the lubricant. In a modern engine full flow filters are fitted which are capable of removing particles as small as 3 microns, whilst older engines may only have a gauze strainer on the pump inlet, which is only able to stop particles greater than 500 microns! To help with filtration modern lubricants contain a dispersant that coats every particle of solid contamination. This additive stops them from sticking together and keeps them suspended in the oil so that they will not sink to the bottom of the sump. In their suspended state they can be removed by a modern filtration system. Unfortunately if the filtration system is not very good this contamination will continue to circulate and cause undue wear. It is even possible for centrifugal forces to push it into the oil passages of the crankshaft, leading to oil starvation. Therefore products with high levels of dispersant should be avoided. A guide to selecting a lubricant with the correct level of dispersant is to use products whose international specifications are as follows: API CC (diesel), API SD (petrol) or MIL-L-2104B (petrol and diesel). Morris Supreme or Elite grades meet these specifications and are formulated to allow solid contamination to drop quickly out of harms way to the sump bottom where it is removed at an oil change. Detergents in the oil stop contamination and products of oxidation (caused by subjecting the oil to elevated temperatures) such as soot, carbons, lacquers, varnishes and acidic sludges from adhering to metallic surfaces. This is a desirable feature and therefore a balanced amount or detergent, appropriate to the engine design, is incorporated into the Supreme and Elite grades.



Very high sliding forces on cams and followers now occur in modern engines, which usually have four valves per cylinder, although loads in this area of the engine have been increasing steadily since the early eighties. In order to reduce or even eliminate initial wear problems experienced on camshafts, automotive lubricants have been formulated which contain more and more anti-wear additives. This is a material that chemically attaches itself to metal surfaces and provides a film that will lubricate in the absence of oil, thus stopping metal to metal contact under extreme loads. However, in new or rebuilt engines this can have an adverse effect. The anti-wear additive plates out on piston rings and cylinder walls inhibiting the bedding in process and in extreme cases can cause bore glazing. Engines running at constant RPM and light loads are particularly prone to this condition. Modern engines have overcome this problem by the use of sophisticated metallurgy and machining techniques. But, of course, this is not so with engines that are approximately more than 20 years old or in some cases younger than this. If an engine falls into this category then oils classified as API CC, SD or MIL-L-2104B as a maximum performance level should be employed.



The above paragraphs have outlined the main differences in the lubricant performance levels required for vintage and veteran four stroke engines, both petrol and diesel. However, modern lubricants have certain features that can be of benefit regardless of engine age or type. These features include improved anti-foam and de-aeration properties, low pour point and good oxidation performance. The oils also have the ability to cope with acidic compounds resulting from the combustion process. This is defined as the Total Base Number or TBN. A TBN value of 4.0 would be regarded as normal for the older diesel and petrol engines whereas up to 16 can be used in the latest diesels. To accommodate the needs of the vintage and veteran engine the Morris Supreme and Elite grades have been specifically formulated to satisfy all of the criteria discussed above. The difference in the two being that the Elite grades have a higher level of anti-foam performance so they can be used in motorcycle gearboxes where there is a high degree of mechanical agitation.





This material is copyright Morris Lubricants 2004 ©.

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kamzack

Great information on lubricants for our engines. If a rebuild is in the near future, is modern straight or multi-vis oils advisable?

And from an amatuer's opion, the occurance of hydralisis in an older engine should be a concern. engines having sat unused for short time or long can have this occur. Causes are; condensation, oil vapors, heat,and cooling. The acid attacks softer surfaces and weakens the leaded surfaces. Care should be taked when restarting one that has been setting. While somewhat labor intensive, dropping the oil pan is ideal as the contaminents and additives may drop out over time. I've pulled dipsticks on engines that have sat and see clean looking oil, don't be deceived, drop the pan and clean pickup and bottom of pan. I've heard stories of old cars being found with clean looking oil, get it fired up only to have a problem develope, knocking "etc", caused mostly by the above chemical reaction. Patience is the first line of defense with old people and old cars.



Thanks for letting me share my thoughts,

Kim

[Deleted User]

I agree that if the engine has not been apart and has sludge in it, it probably has only had non-detergent oil in it and if it runs ok stick with the non-detergent oil especially if it is a splasher engine. Don't do like I did and put detergent oil in it and other things to clean it out because it will stop up the oiling holes when that sludge breaks loose and will stop the oil from getting to the main bearings and cam bearings. That is just my opinion.

bmcgill