Via Veloce by Wille R. www.veloce.se On the Internet since November 1995 and still here. The oil does the hard work in the engine. If you have doubts about your oil pressure, you may check the pressure like this whit a cold engine. Start the engine and let it run for say ten secs. Then turn off the engine and as soon at it has stopped, quickly turn on just the ignition. If the red oil pressure warning light on the panel takes some secs to light, the engine is holding the oil pressure OK. The duration for the oil gauge comes from the fact, that the oil in your Alfa has a long way to run until it reaches the sender unit. I suppose you have your sender just over the starter on the rear back, far right. The sender for the red light is placed rather close to the oil pump on the exhaust side. Oil classification The API (American Petroleum Institute) have this system. S means service class for petrol/Otto engines and C for commercial class/diesel engines.
The oil is very popular on TV! The engine oil is a popular event on the commercial TV. It's being grilled over an open fire and then expected to be liquid after ten hours in an arctic climate. We might even have the chance to accompany the oil in the engine through pistons, valves, bearings and down into the big black sump. This is in fact only the beginning of the oil in your engine. It's a cruel world down there in the sump. We sure expect the engine oil to do a great deal in our Alfa Romeo engines. The oil must stand three times the temperature of boiling water. The oil must be able to lubricate valves that are accelerating as fast as 1000 g. A human being will get unconscious at 7 g. The oil must also lubricate pistons that might reach a speed of over 5000 km per hour. That's fifteen times as fast as s bullet from a rifle The oil must hold a film to lubricate the bearings that may reach a pressure that's 12 times the pressure in your bathroom pipes. The oil does not look as gorgeous or as attractive as your car stereo. But it's down there in your engine, doing a marvelous job. The oil companies are developing engine oils and their additives like never before. However, one point needs to be concerned. Reduced fuel consumption is hardly the result of changing the engine oil from one make to another. It's more likely to be the driver himself who effects the miles per gallon ratio. Drive nice and you'll improve your economy. There are five important tasks for the oil. To reduce friction. To clean the inside of the engine. To prevent corrosion inside your engine. To cool and reduce the temperature inside the engine. Finally to tighten the engine and reduce any leak of oil. The first item is obvious. Any contact between the metal surfaces in the engine is critical. With a cold engine just at its first firing, the oil additives will take care of the friction. That's why it is so important in cold climate to use a recommended oil of very good quality and to have the engine running at low revs for a while until the oil is warm. The Alfa engine has quite a considerable volume of oil in the sump and it takes time to reach its recommended temperature. Drive your Alfa gently the first minutes before you use its full potential The second task is to clean your engine. In fact, your engine is like a washing machine. In the oil there are additives like tensides like in the washing powder, to remove any dirt inside the crankcase. Another additive will hold the dirt fluent until the oil filter hopefully cleans the oil. Any filth and small dirt like carbon and metal particles that's being washed down from the liners by the pistons will be held by the filter. The very small particles that my pass the filter will give the oil a black color after a while. Black engine oil is no problem, it is a result of a good engine oil that is cleaning the engine and doing its job as expected. The third task is to prevent your engine from rust and corrosion. The combustion process generates water and acids. They are mixed with the engine oil and become real nasty. In the end they may cause rust on the metal in the engine. If the rust wasn't prevented and stopped, the bearing tolerances for instance would change and cause a damaged crank shaft. Since the oil contains basic additives to neutralize the acid, all you need to do is to run your Alfa real hot for a while, like the Italian tune-up myth. See Pat Bradens Alfa owner's bible. Once the engine is real hot and the oil too, the nasty things will evaporate. This is one of the reasons for a regular change of engine oil. I always change oil in my Alfas once a year or after 10 000 kms, which ever comes first. Don't forget to change the filter too. The fourth task for the oil is to cool the engine. Most of that job is taken care of by the coolant, but inside the engine the oil has to do this. The pistons are one of the hottest parts in the engine. The temperature might reach 300 degrees there. The oil is also cooling the liners and the bearings as well as the valves and the head. Hard work to be done for the friend in the sump. We hardly see anything of this working oil. The fifth task is to keep the engine tight. Again, high temperatures helps the oil to keep the pistons and rings close to the liners to improve the combustion process. It must also keep the valves tight in the guides to prevent oil in the combustion chamber. Imagine that! What about the oil temperature?. If you have access to a temperature gauge, you will notice that the temperature will increase at high revs. If the engine is working under pressure, say heavy load in the trunk or hill climbing, the temp will also increase. This is no problem with a good quality oil in the Alfa alloy sump. But what is the normal temperature? First of all, the oil must not be too cold. The more viscous, the longer it takes the oil to reach the bearings. Did you know that even in the summer it might take the oil some minutes to reach its full lubricating potential. That is why you should rather not rev your Alfa too high the first minutes before the oil is warm. To have the water and acid to evaporate, the oil must be somewhere around 100 degrees. If you drive your Alfa on a short distance without the engine being warmed up, you may find a light brown foam inside the oil cap. This is nothing to worry about, some Italian tune up will solve that problem. The temperature in your Alfa is probably around 110 to 130 degrees. If you drive it very hard, an oil cooler might be needed. See your Alfa supplier on my hot links to get one. If your Alfa wants oil it's OK, but if the consumption is increasing, check the head and the pistons. The job can be carried out without removing the engine. See my tips on this site. What about new synthetic oils? Well, in fact I drive with Castrol 20/50 in my Spider but use synthetic oil in my other Alfas since 1990. Since my Spider was born and raised with Castrol I prefer to continue to use that oil here. The photo shows the cam covers. The left was in an engine using modern high quality, semi synthetic oil and the right cam cover comes from an engine which has been running with regular mineral oil. The left one is as you can see very clean compared to the right one. The new modern engine oils are very effective and clean the inside of your engine. The filter will take care of the dirt. You will need some 6,5 liters, i.e. 7,1 qts incl. the oil filter when you change.
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