what oil?

[RobCapper]

must be the season for dopety questions from myself - please excuse them - I'm learning...!
exactly what 'weight'? or whatever it's called of oil am I supposed to be using? Over the past 2 years, different mechanics have advised all sorts pof things, and it's currently using the mobil 1 motorsport 15w 40 stuff...

is this correct? Or doesn't it matter? I know it's something that one can get quite 'precious' over, and that some choose only to use v expensive millers products etc, but I'm not that rich, and like i say, get through the stuff, as I do 15,000 miles a year..

The engine has started leaking quite badly recently (never previously a problem at all). Could this be influenced by the oil I'm using, the hotter temps that it's running in this weather, or is it prob symptematic of something broken/lose/dying...?

[elans3]

Hello Rob, many of users of old cars have been advised to use the Mobil 1 type oil, which is an excellent if very expensive choice. I would only recommend it if the engine has been rebuilt using new seals, and utilising all the modern sealing aids that are available now. If you are using it in an engine that hasn't been rebuilt for some years, then it is highly likely that it WILL leak profusely. This makes using these modern, excellent, but expensive oils even more costly.
I have a 66 S3, rebuilt 2 years ago, and use only Duckhams 20/50, an oil that was cutting edge in the 60's. Some people have found it difficult to get hold of, but I have a local guy who frequents Newark Autojumble, and he keeps good stocks.
I know that there are people that will not agree with my approach, however this was an oil that I have used prodigiously in Twincams between 1973 and now, and this included road and stage rallying to national level, and I never had one problem with any of these self built engines, using Duckhams 20/50. Always the engines were pretty oil tight too. This Competition work obviously includes very high revs for long periods.
I have had sojourns with different cars also.
5 years ago I had a mint 1970 Porsche 911E, which had been extremely well cared for, and run on 20/50. I had a long conversation with a Mobil 1 rep at a Porshe show, and tried a refill with their product. I have absolutely no complaints with the oil, but within a few days, the motor began to leak like a sieve.......... Bear in mind that these 911 engines hold around 17 - 18 pints...... A very expensive lesson.
I drained it and went back to Duckhams, and the leaks disappeared within a very short time.
Another Porsche show some months later, and I regailed a different Mobil 1 rep with the story. He had a completely different approach, and said that he would never have advised using it in an engine that was running well, leak free, and hadn't been dismantled recently.
so this is the way I've dealt with the subject.
If you don't want to strip the engine for the sake of it, get hold of some good quality 20/50, (ring Duckhams for your nearest outlet, mine costs ?6.99 for 5 litres by the way) drain the oil you have in, and see if it makes the difference to your leaks.
I still drive my S3 the way it was designed for, and it performs faultlessly with superb oil pressure both hot and cold, and it has done about 3500 miles since being rebuilt, and more importantly doesn't leak. I should add that it may well not have leaked with Mobil 1, as I did use the modern sealants to accompany the new gasket set, but I believed that the old product was still good enough to work well.
I hope this helps.

[1964 S1]

I've been running Castrol GTX 20w50 in my Lotuses for decades with no hint of a problem.

[john.p.clegg]

Duckhams 20/50 gets my vote...

Also a regular at Newark
(next one in September?,am suffering withdrawl symptoms,did you do Kelham?-Was it as good as Newark?

Thanks
John

[cliveyboy]

Without sounding like an echo.
Castrol GTX or
Duckhams ( my personal favourite).

Dont get carried away thinking that as there are new wonder oils about, the old stuff in no longer any good.
GTX and Duckhams may have been around for years but they have been constantly improved over the years.
And most importantly there are the correct grade.

Clive

[Elanintheforest]

I found that Duckhams held better oil presure than GTX when the engine gets really hot. And this advert probably clinched the deal....who said advertising doesn't work?!

[thor]

I also have good experience with 20/50 in the past, stopped consumption and upped the pressure on my previous Triumphs. The easiest to get hold of here is the Valvoline Racing 20/50. But I have to wait now as mine doesn't consume any for some STRANGE reason...

[Emma-Knight]

lovely picture!

(...so cool...)

[Dag-Henning]

- one of my best friends , - technical manager lubricants Castrol Norway-, has supplied me "Castrol R 0 - 40", which I have been using for racing last two seasons without problems of any kind. Obviously, our twinks were designed when oils were a bit different, but if you can maintaine a good pressure when the oil is up to working temp, and change oil /filter regularly, you will be safe whatever (almost) you choose to put in.......
- and that started the party.....

Dag

[reb53]

Always used Duckhams 20/50. Used to buy 20 litre drums.Made no difference to how much it leaked, (!), and there was no way I was going to pull the engine to save myself a few dollars worth of oil!
Now have a couple of hundred thousand miles up. Re-bored twice, now on +30s, crank ground once so plenty of life left yet.
Have always replaced oil and filter every 6000 miles which I suspect has more to do with longevity than oil choice, within reason!
Good thread here a while ago re additives for twink tappets.

[gjz30075]

Back in the early '80s, a friend became an Amsoil dealer. At that time it was the leading edge synthetic oil. I was obliged to buy 4 quarts for my Toyota to 'give it a try'. As usual, I changed the filter with the oil change and when I fired it up, most of the 4 quarts ended up on the ground. Turned out that the filter gasket had not come off with the filter and was stuck to the block so the new filter never seated properly. Now, this has NEVER happened in the previous 60k miles worth of oil changes and NEVER happend again, after cleaning up the mess. I think my car was telling me somthing!

[marcfuller]

I would suggest using Quaker State Racing 20-50 (my choice). Or if cost is a concern Rotella 20-50.

The oil that was made for our Elans is no longer available (the formula has changed), although the brand names are still around. So this should not be a brand name centered discussion, but a formulation discussion. You need to have an oil that is designed for flat tappets and the valve spring pressure present in an Elan.

Contemporary motor oils are now formulated with a great deal less pressure lubricant than was present just a few years ago. The reason for this is that the pressure lubricant is a zinc/phosporus compound (ZDDP) that "poisons" catalytic converters. The pressure lubricant is most important for the friction surface present at the tappet and cam lobe. New cars are able to forgo the zinc/phosporus because of the wide spread adoption of roller tappets allows for much, much less ZDDP. New car makers and regulators would like to eliminate ZDDP in motor oil, oil makers try to keep some for older engines. But there is little science as to the minimun needed and the current common formulation is much less than 50% of what was present just 10-15 years ago.

The motor oils that retain the level of zinc/phosporus present in oils when our Elans were young and catalytic converters unknown are true racing oil like Quaker State Racing oil (no API and not "street" approved in the US), most motorcycle oils (other than BMW) and diesel engine oils such as Shell Rotella.

[thor]

Any difference between motorbike oils and car oils....?

[tower of strength]

Hi Guys,

I ran my plus 2s130/5 on valvoline racing 20/50 with no probs, I tried a 15/50 but the engine was a bit of a rattler on start up, so changed back sharpish!! I found that the oil needed very regular changes as although she burnt a bit, the level never went down (excess petrol washing past the rings). I used to change oil and filter every 1800-2000 miles.

Modern synthetic oils like Mobil 1 would be OK in a freshly rebuilt engine with very fine tolerances, but shouldnt be used in older/higher mileage engines (from the Valvoline rep)

My mum ran a +2 for 5 years as a daily driver (30,000miles) on Valvoline with no problems at all (XWC56F if anyone knows of its whereabouts)

regards

Mark

[thor]

My thoughts exactly-. On my TR4A, changing from a 10 or 15W40 to the Valvoline 20/50, the oil pressure went up, and the consumption went down by 70%. My +2S bought a year ago doesn't consume any oil, but on my next change, there's no doubt in my mind..