I find it odd that regulars of this forum still debate what is the right stuff after so many threads on this.
My advice is just make sure it has oil in there. I change or top mine up that often I can't see it matters that much. Tried fixing the leaks but it just don't seem to happen. Bump3r
No idea. All oil'll go black eventually. If running an engine really hot has cooked the oil, you can smell it - an evil burnt smell.
Synthetic oil is better, which is a fact. Normal multigrade is distilled from the crude and then has modifiers (polymers) added to give the oil the appropriate characteristics. The oil itself contains a wide range of molecules because it's a direct distilate, so the lighter stuff tends to burn off and degrade faster. The polymers themselves also break down (especially with heat, and air cooled engines tend to have hot spots due to the inevitable uneven cooling) and the oil loses its lubricity and its multigrade properties degrade. Synthetic oil uses synthesised molecules to give a much tighter spread of molecule size in the oil, meaning that there are more of the oil molecules that you want and less of the ones that you don't want. It also minimises the requirement for polymer additives. Combined, this means that the oil itself lasts longer and so keeps on lubricating properly for longer. Cheaper oil = worse quality distilate = more (and cheaper) polymer additives = shorter life. Whether or not it's worth it in a T2 is another matter. If you are constantly topping up to replace leaking oil, then you probably won't notice the difference as you're effectively changing the oil very frequently anyway, before it has a chance to break down. If your engine is oil tight and goes the full interval between changes, your engine will wear less with better oil. Buy what you can afford, but the synthetic is better in the long run.
I use the cheapest 20/50 I can get for all my old aircooleds (85 BMW R80, 82R80G/S and my bus). I know that fully synthetics have been known to cause problems on older engine's oil seals on the bikes... The oil gets a real caning on these buses and I do a lot of short hops so I tend to swap out my oil every 2K. seems to be holding up.. Sorry if oil discussions bore the old hands on here but we do get new people wander by... Cheers s
^ this. You need to change the oil at 1970s periods anyway, as you haven't got an oil filter (on a type 1, anyway). Carbon and other deposits will be slowly sandpapering your bearings if you leave oil changes any longer. Spending the extra money for synthetic on a full flow filter is probably money well spent, if engine life bothers you. A hardworkng type 1 will be knackered after 50k, anyway - that's how they were designed.
There is a bloke on here that does testing of materials for a job and one day, as I remember the story, he an his 'geeky scientist colleagues" ran numerous computer models on all the types of oil and deduced that none of the new synthetics or part synthetics actually worked any better than the old mineral oil, in fact the mineral oil out performed.
This is getting a bit surreal now, lads. Oil, of whatever type, will go black. It's picking up carbon from combustion, which is part of its job. Never noticed this on the dipstick of your modern car? I'm assuming here you do do check the oil ... Oil needs to get pretty hot - hotter than you'd get in an air cooler - to get damaged. If it has overheated, it stinks. If you've got a type 1 engine, there's no point in stretching oil change intervals - you've only got 2.5 litres of oil going round and round, and you've got no oil filter to trap those carbon particles. Leave it a long time and it acts as liquid sand paper on your bearings. If you look in the handbook for your bus (which you've got in the glove compartment, obviously ), you'll see that VW specified a mineral multigrade from fairly early on. No point in using a mono grade, especially 30 which is too thin for a hot air cooler IMHO. Morris never called their 30 grade an "air-cooled oil" - it's a VW myth. PS You don't need a blue ignition coil, either
Just to resurrect the thread and for my tuppence worth as I don't think the original question gets asked enough I've got a 2.0l FI engine and it runs just peachy on 15W/40 mineral.
