Pierre Gillet Posted August 4, 2000 Share Posted August 4, 2000 I just checked today in the two Hypermarkets close to my home where I normally buy the Rosé wine I drink in the spring/summer time ( I shift to Red during autumn/winter) when I do not drive my Seven. It is about 250 FF for 5 liters either in 0W-40 or 15W-50 . As for my car , I am using a generic synthetic 5W-50 @ 135 FF /5 liters. The grade range numbers are certified by an American Bureau ...so it cannot be that bad! In fact I have not still noticed any oil pressure drop during road and autoroute use. Pierre Link to comment Share on other sites More sharing options...
CHRIS CLARK Posted August 4, 2000 Share Posted August 4, 2000 Pierre, With multiple entries like that are you sure you're not filling the car with wine & drinking the oil! Or maybe just enjoying too much of the vino. Link to comment Share on other sites More sharing options...
John E Posted August 5, 2000 Share Posted August 5, 2000 I think he's using the bloody oil to lubricate his throat in preparation for a right good skinful. It seems to have nic hic hic wooorkd Link to comment Share on other sites More sharing options...
Area Representative Crudders Posted August 10, 2000 Area Representative Share Posted August 10, 2000 Too right - there's usually a large empty space on the shelves of the "Super U" in Arnage every year on the Le Mans trip where the Mobil 1 used to be - understandable as it's about 160FF per can. Why is that? Is it another example of "Rip Off Britain"? I use castrol RS in my crossflow and 4 litres of that stuff is £29.99 for f**ks sake! For what it's worth I ran my crossflow on Mobil 1 for the first few thousand miles and it proved to be a bit too thin - ****ty oil pressure when hot and high crankcase pressure cos it wasn't gloopy enough to seal the bores properly. Obviously not a prob with your modern motors though. While I'm on the subject, I was told recently on good authority (actually it was a gob****e down the pub) that synthetic oil is a bad idea in older engines cos it degrades the oil seals. That might explain why my engine coats the underside of the car, the garage floor, the drive, the queen's highway, in fact EVERYTHING in VERY EXPENSIVE synthetic oil but is it true? Would I be better off with Castrol GTX at a quarter of the price? Any oil experts out there? Crudders Link to comment Share on other sites More sharing options...
Slipper man Posted August 10, 2000 Share Posted August 10, 2000 I am not an oil expert, but those I know have told me much the same. Older engines have much higher tolerances between all the moving parts, and therefore need to use thicker oils. On my last BDG, the engine builder was adamant that I must never use a modern synthetic oil, but a 20/50 multigrade at half the price. His advice was to use the oil the engine was built for - modern engine, modern oil; old tech. engine, old tech. oil. Seemed logical to me Link to comment Share on other sites More sharing options...
fastforward Posted August 10, 2000 Share Posted August 10, 2000 For what it is worth, the guy who last did my MOT was a mechanic for a Seven racer in the mid 90's. He said there is a lot of nonsense, he used the venacular so it must be true, talked about oil and that xflows do not need expensive Mobil 1 and I went retro and put in Valvoline. We change the oil so often and I do not personally race for hours round the 'ring. No complaints and the oil looks new so far this year and none of it is come out any of the orifices. Brian brianfyfe@ema.org.uk Link to comment Share on other sites More sharing options...
Ray Stewart Posted August 14, 2000 Share Posted August 14, 2000 Have just caught up with this subject and was very impressed by Pierre's multiple entries. However, back to the subject. I checked last week with Western Road Garage (Paul Harvey's garage) and was told that they used standard Castrol oil in my Crossflow at the last service. Keith's and Brian's point about old style engines needing old style oil also seems to make sense to me. Although I don't do track days my right foot gets very heavy when I'm in the 7 and the oil still looks fine before a service. However, I would rather spend the extra money if it helps to reduce wear on the engine. Link to comment Share on other sites More sharing options...
Vogon SuperTrooper Posted August 14, 2000 Share Posted August 14, 2000 This is a really thick question, so apologies in advance, but what makes the oil discolour? I'm talking about clear gold to jet black. Is this a problem? thanks Resident Idiot. ps. Don't worry, there are many more where this gem came from... Link to comment Share on other sites More sharing options...
StewartG Posted August 14, 2000 Author Share Posted August 14, 2000 Apparently the oil turning jet black in no time at all is due to petrol contamination caused by Webbers being extremely liberal with our petrol especially when the accelerator pump is used heavily i.e. all the time. This presumably means the oil film is to some extent washed off the bores. I wonder if thick oil is harder to wash off? or is the amount washed off proportional to the cost of an engine rebuild? Link to comment Share on other sites More sharing options...
Vogon SuperTrooper Posted August 14, 2000 Share Posted August 14, 2000 Hmm. I'm not sure I like the sound of this. Signs are pointing towards 'large hole in bank account', twinned with 'Angry wife', and I can tell you, free, that this is not a pretty place to be. Or am I just being wet? Link to comment Share on other sites More sharing options...
Mike Bees Posted August 14, 2000 Share Posted August 14, 2000 I seem to remember that the oil going black means that it's doing it's job. Hopefully Roger will be along to put us straight! Mike Link to comment Share on other sites More sharing options...
Vogon SuperTrooper Posted August 14, 2000 Share Posted August 14, 2000 That would be an especial bonus as he partially rebuilt my engine. BTW, Mike, and with no relation whatever to this string, I'm writing an article on females in IT. Any thoughts? thanks chalrse Link to comment Share on other sites More sharing options...
StewartG Posted August 14, 2000 Author Share Posted August 14, 2000 It's not for Low flying is it? Link to comment Share on other sites More sharing options...
Vogon SuperTrooper Posted August 14, 2000 Share Posted August 14, 2000 No, I just happened to be doing two things at once. But on the subject there just aren't enought women in sevens. Are there? c PS Mike Bee's in IT too, you see. Edited by - Charles WRX on 14 Aug 2000 18:03:06 Link to comment Share on other sites More sharing options...
Area Representative Crudders Posted August 15, 2000 Area Representative Share Posted August 15, 2000 I always assumed that the blackness was a by-product of the combustion process (i.e. carbon) that finds it's way past the piston rings, up the valve guides etc. but then I'm no oil expert either. Thanks for the tips you guys, I'll buy a quality 20/50 in future and change it more often. Maybe the oil seals will show their approval by keeping some of the oil on the INSIDE of the engine. Hopeless optimist? Moi? Crudders Link to comment Share on other sites More sharing options...
Roger King Posted August 15, 2000 Share Posted August 15, 2000 I can make no claim to being an expert on lubricants (not quite sure that brings the right mental picture to mind!), but as an engine builder I can tell you that Crudders is about right - the oil goes black as it absorbs the products of combustion (and also microscopic metallic particles) in suspension. This is meant to happen, but you get to a point where it needs changing. As you might logically expect, it is quite noticeable that this blackening occurs faster in an engine with piston rings and bore that are below par. If you build an older type engine to modern standards of bore finish, bearing materials, piston ring design, etc, then I can only say that I would always recommend a synthetic oil over a mineral oil except for the first 800 miles of running in. If there ever was any truth in the story about older seals being affected by synthetics, this will be irrelevant if new ones are fitted. It is very noticeable how much cleaner an engine stays internally when synthetic has been used (especially in very hot areas like the underside of the piston crown). Personally, I like Mobil 1, but I'm sure that others will be loyal to other brands. Don't forget that just because oil seems thin when it is cold (like the 0w/40 Mobil 1), it doesn't necessarily follow that it will be like water when it is hot. The first number in the designation (0w) refers to the oil's viscosity when cold, whereas the second number in the designation refers to it's viscosity when hot, (40). Viscosity when hot will be the same as any other oil that has 40 as it's second designation; therefore if you compare it with a 20w/40 oil, this will be much thicker at ambient temperature, but the same viscosity when it is hot. Does that make any sense? Talking of running older engines; my fifty year old sidevalve lawnmower is running on Mobil 1 (mainly as a satirical gesture), and it hasn't complained yet. Link to comment Share on other sites More sharing options...
Moderate Clam Posted August 17, 2000 Share Posted August 17, 2000 When my engine gets hot (i.e. sitting in long traffic jams whilst trying to get to the coast), the oil pressure drops quite considerably (I'm using Mobile1 0w/40). This is just on tick over (picks up as soon as I start moving), but DVAndrews was saying that he was still getting high pressure when hot and on tick over. Does everybody/anybody else get this, or should I switch to Mobile1 15w/50 (or even Castrol 0w/50... if I can afford it)? Would 50 help dissapate heat better as well as remain thicker? Link to comment Share on other sites More sharing options...
Pierre Gillet Posted August 18, 2000 Share Posted August 18, 2000 Ooooops! I really apologize for the multiple entries...I just discovered today that you need to click on the following page number to see it on the screen and I was desperately clicking to see my message on scree. I thought I had a problem with my modem...( yes, I am a beginner relative to the forum although I have been recently promoted to the Angel level to my great surprise, probably because of the number of my naive questions). OK, I am discovered now and hope that I will not be "retrograded... Again to you all my sincere apologies. Cheers, Pierre Link to comment Share on other sites More sharing options...
Northern Banana Posted August 18, 2000 Share Posted August 18, 2000 I've posted a similar query regards oil temp and pressure on another page, (I won't repeat it here) but would interested to hear of thought on hot idel low oil pressure. Also, should a special specification of oil filter be fitted or is the Halfords/Rover version OK for a 1.6 Supersport, now doing a few track days? CHEERS Link to comment Share on other sites More sharing options...
b.fitzsimons Posted September 8, 2000 Share Posted September 8, 2000 On the subject of oil choice, I made a concious decision to give my trusty old Kent engine a trear of Castrol RS Synthetic oil. Lucky blighter I thought until I had a look at the bores at the beginning of this year, after thrashing it a fair bit last year in successful efforts to keep Gordon behind me. The bores had glazed and I was a little concerned. It may have beem wear and tear but I had my doubts, so I called Castrol. I spoke with a chap in their technical department who reckoned I had made a mistake in switching to synthetic rather than staying with mineral based oils. Apparently the synthetic base is NOT very resistant to fuel washing of the bores, whereas mineral based oils show more resistance to fuel washing. Fuel washing is a common feature of carburettor fuel systems running rich (my engine runs between 3% to 6% CO depending on the operating conditions). However, this may also be the case for fuel injected engines where excessive fueling is used to cool the pistons (an example of an early K I measured ran at 6% CO on full throttle) I now run Valvoline 20W50 racing oil as recommended by Burton and have not seen any further deterioration in the bore condition. Has anyone else had a similar experience in switching to synthetic ("nectar") oils? Link to comment Share on other sites More sharing options...
Alex Wong1697456877 Posted September 8, 2000 Share Posted September 8, 2000 Poor Gordon... Everyone seems intent on going faster than him. Welcome to Blatchat Brian. Have you seen the revised sprint classes? I'd value your opinion, especially as you will be getting some extra competition as a result of them! Alex Link to comment Share on other sites More sharing options...
big daddy Posted September 8, 2000 Share Posted September 8, 2000 Well, who wants to be beaten by a powder puff? Link to comment Share on other sites More sharing options...
Anna Rexia Posted September 9, 2000 Share Posted September 9, 2000 Charles, Tamara thingy-whatsit is supposed to be an IT girl is that the sort of thing you're looking for (what does it mean anyway - irritating tramp?) Link to comment Share on other sites More sharing options...
EFA Posted September 11, 2000 Share Posted September 11, 2000 OK, Now Roger, who I know is an expert said: Don't forget that just because oil seems thin when it is cold (like the 0w/40 Mobil 1), it doesn't necessarily follow that it will be like water when it is hot. The first number in the designation (0w) refers to the oil's viscosity when cold, whereas the second number in the designation refers to it's viscosity when hot, (40). Viscosity when hot will be the same as any other oil that has 40 as it's second designation; therefore if you compare it with a 20w/40 oil, this will be much thicker at ambient temperature, but the same viscosity when it is hot. Does that make any sense? So howcome on my Vaux, the oil pressure drops to 35psi bar when thrashed fro 20 mins at 8000+rpm on a track day on Mobil 1, but stays above 55psi bar if I use Comma Syner G (Pre Syner Z but I've got loads in my garage...) Bothg oils havce a "hot" viscosity of 40, but the "cold" visco of the Mobil is 0 wheras the Comma is 5. Are we all sure we have our figures the correct way round??? Arnie Link to comment Share on other sites More sharing options...
MissQuote Posted September 11, 2000 Share Posted September 11, 2000 I don't know about your figures but mine are 34-24-34 so it doesn't matter which way round I am or how long I've been thrashed for. Link to comment Share on other sites More sharing options...
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