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MG MGB Technical - Lucas classic oil

I spoke to my local factors recently about classic oil and they suggested Lucas 20-50 as the best. It has high levels of zinc(2100ppm) molybdenum and phosphorus. Anyone have any experience of this and any advice as to whether it can be used in engine and overdrive gearbox?
Rod Merrall

Heard of it, made me smile given some of the comments about Lucas electrics from across the pond.

Loads of Lucas 20W/50 oils apparently available, from this zinc values data sheet http://www.lucasoil.co.uk/images/documents/Zinc_Values_MotorcycleOil.pdf, with values from 861 upwards.

2100ppm seems to be hot-rod and classic car oil, so you would have to be sure you were getting that product i.e. 10689 to get that level in that viscosity. Googling seems to show plenty of suppliers near me, but after that it would be a case of ringing round for availability and price. Quantity seems to be in quarts.

Maybe overkill for pottering round country lanes, and especially for the gearbox, as far as I'm aware high levels of zinc are not needed there unlike for cams and tappets.
paulh4

I am not sure that any amount of ZDDP is enough any more. The last three camshafts I have pulled have been had some damaged lobes, but typically not all. I have tried oil formulated by a small blender who makes specialty oils for flat tappet farm equipment engines as well as Valvoline's recent 20W-50 Racing blend. I have also added ZDDP treatment.

I wish that someone would come up with a direct replacement roller tappet that would replace the flat tappets that no longer seem to work. I put 171,000 miles on the original midget engine with no visible cam damage. Now I am lucky if I can get 20,000 miles out of a cam in the B or the Midget.
Glenn Mallory

It's more a case of being a pity that manufacturers can't make the components to the original standards, I suspect, as with rubber components.
paulh4

I agree with Paul, that the modern parts quality is suspect rather than oil modern oil quality.

ZDDP is NOT the be-all-and-end-all additive, if you want lots of it fine, have it but don't get too hooked up the the large numbers of ZDDPs. The oils including their additive packages weren't as good when our cars were new.

When you want protection one big guy isn't always the best, a team is more usually better.

But let your oil belief be with you.
Nigel Atkins

From 1965 through 1971 the then current API Standard for motor oil was the SC standard. SC motor oils contained up to 800 ppm ZDDP, exactly the same standard as SN oils today.

Cams were not prematurely wearing out in the 1960's with those levels of ZDDP.
Steven Rechter

References?

These indicate that ZDDP and particularly phosphorus which is the anti-wear additive has been greatly reduced in successive formulations since catalytic converters were the norm on modern cars.

You also have to differentiate between 20W/50 and lighter viscosities, the latter having been reduced, but so have 20W/50 from sundry manufacturers. You have to look at the spec sheet for each to stand any chance of knowing what there is in terms of ZDDP.

But even when the ZDDP has been reduced, it may well be that other ant-wear additives are in place, but they will be designed for modern engines and not our flat-tappet engines.

http://www.mototribology.com/articles/categories-and-their-importance/

https://www.transdiesel.com/blog/passenger-car-motor-oil-blog

https://www.duckhams.com/zddp-what-does-it-all-mean/
paulh4

Paul,
read the 'references' in the links you have put up, in them you will find -

. not all ZDDPs are the same
. the rest of the additive package is important
. the additive package, including whichever ZDDPs, needs to be balanced
. beyond a certain level ZDDPs numbers are too high/much
. the quality of the base oil is very important

You are arguing against yourself with those references, but you're blinded by your belief.

Where Steven has put 60s oils having UP TO 800 ppm of sme sort of ZDDP, I've previously seen a figure of 600 ppm given and of course was either of those figures really required or definately required because of the rest of the make up of the less sophisticated oils of the 60s.

You're stripping out the nuances and just going with crude numbers of ZDDPs as if they're an army of ants, but what sort of ants are they?

You are not wrong with sticking to the sort of oil you want to use but neither are others in using different and better oils.

Nigel Atkins

'Arguing against myself' is me saying it's nowhere near as simple as Steven suggests, which is why I posted three links which give varying information.

The 'belief' I have regarding ZDDP is that in my own experience modern formulations wreck replacement cams and tappets in all too short a time, whereas older formulations don't, and 'old' cams and tappets that have done many tens of thousands of miles on older formulations don't seem to suffer either, hence my comment of 20th June.
paulh4

For years I was buying the cheapest 20W-50 I could get, but with regular oil and filter changes. At the time that was a Wilko oil, but then I noticed bits in the bottom of the plastic can, so upped the ante to Comma Motorway. Then they seemed to do a slightly posher Comma X, so went for that. After a tour of Formhall's Vintage and Racing in Downton last year with a car club, their lead engineer said that ZDDP does seem to make a difference to an old engine, so now I've switched to Comma Classic 20W-50 (which includes ZDDP), and which I believe is the same as Halfords 20W-50. Not sure about the efficacy of any of it, but I'm guessing that if case hardening was wearing away on tappet adjusters, cam or cam followers, I'd need to be adjusting valve clearances every five minutes. Haven't done so in years and many, sometimes hard, miles.
Peter Allen

Peter,
IIRC Wilco, classic oil at least, is (or was) an oil made by Comma same as IIRC Halfords Classic - look in the various Archives here to confirm rather than go on my poor memory, I've posted the data sheets and info a good few times.
Nigel Atkins

Paul,
it's a belief because you don't have the necessary evidence, how do you know that the modern parts wouldn't have also been wrecked by the 'older formulations'. Why weren't the parts in my engines wrecked during many tens of thousands of miles - that's my experience, is it evidence or belief (you've decided).

As a matter of balance on engine oils I often put up three hyperlinks, without comment on them, one is to your site with the oil beliefs, so that others can pick the belief that suits them. Using the type of engine oils you promote isn't wrong.

The older formulations are modernised anyway, as per your Duckhams link.

It may be that it's just a matter of definition between us, what's a modern oil, Mobil 1 goes back decades, and when I used it decades ago in my Bs (which weren't driven maiden-aunt like) I was told by people like you that it would ruin my engines, it didn't. Oils have improved since then too.

Blenders and producers can now market oils with high ZDDP numbers to satisfy the demand from the fashion, same as changing the packaging to look more classic to appeal to those buyers and probably are able to add a premium to the price because of the demand.

A good oil is a good oil, old style or very modern, of course you do need to use the appropriate oil but that isn't just on the number of (whatever type) of ZDDPs so don't get too fixated on them.
Nigel Atkins

Nigel, the Wilko oil I was using was one down from their Classic, something like 'Everyday for old high mileage engines'. I reckon it might have been reclaimed.

I remember when Mobil 1 synthetic came out, or became popular, and everybody swore by it. It was comparatively expensive, whilst I soldiered on with my mineral Duckhams 20w50. My brother used it in his nearly new XR2 - ironically, the sort of vehicle for which they'd now recommend a classic 20w50. As you say, fashion.
Peter Allen

I remember when I was buying Mobil 1 it was £24 a can but you got a £4 Argos card back with it. Then it went on to things like large umbrella and then onto the thinnest luggage sets known to man.

Marketing, you keep the price up (or put high ZDDP numbers) to appeal to your purchasers.
Nigel Atkins

Glenn, are these repro cams or new billet?
Peter Burgess Tuning

Interesting little addition to this for you
Here in Aust, there was a Ford Falcon with a 6cyl pushrod engine which was ultra reliable--Half way through the model run Aust switched to unleaded petrol --The Falcon got a cat., different ign. and a reshaped combustion chamber and that was about it
They absolutely ate camshafts, can the change to unleaded petrol be effecting the oil enough to eat camshafts---???

My current oil of choice for the MGs I look after is Penrite Diesel 15, It's a 15/50 semi synthetic and has all the goodies in it and seems friendly to MGs-------so far--It's a detergent oil as are most diesel oils so a good engine flush on anything with a few Ks on it is a must
William Revit

I doubt it was the fuel affecting the oil.

It sounds like the lubrication of the cam was marginally safe initially and the changes increased the cam / follower loads sufficiently to cause the issue.
Chris at Octarine Services

As in all walks of life, we tend to become prisoners of our own experience. Duckhams 20 - 50 did well in 1965 and those of us who remember look for an equivalent today. Times and oil have moved on. ZDDP was the definitive solution then.
Is there a better solution now ? The manufacturers are cagey about the additives they use to deal with cooling and friction in the latest high output engines.

A chance conversation on a summer afternoon at Goodwood suggested that Mobil 1 has what we need. What is it ? The proven slippyest anti-friction substance known ? Mobil 1 costs more than the rest. Does it include the stuff ? The options are to pay up or add it separately. faher.com if you read Spanish or faher.co.uk if you prefer it in english will tell you what you need. Read the testimonies - we don't have a maserati - the volvo V60, modern mini, GT 3.9, B Roadster 1800 and MGA 1500 all run trouble free and noticeably quieter with 3% in our own choice of oil . We no longer think about ZDDP.
Roger Walker

You're probably right Chris ,but it's just a bit weird that the issue began then on the exact same camshaft, same timing ,same part number


On the Mobil 1 thing-
I used to prepare an old side valve Ford V8 for a guy for Targa type events and always ran 15/40 mineral oil and it was fine running at around 50psi op on the road--The guy that owned it was the Mobil oil distributor and wanted to change to Mobil 1 so we did--Started up fine cold with around 40psi idling and out the road it had 60 to start with but by the time we got back from the run ,probably 10klm it had 0 at idle and about 10psi running. We thought something had happened to the relief valve so got in and checked all that --ok--Decided to go back to the original 15/40 and all was well
I think it was just a case of the modern oil was just not compatable with the larger clearances and oil loss spots in the old side valve---it's still going fine on the 15/40 mineral oil
William Revit

Hi Willy,

I've been using Shell Rotella 15/40 (mineral) Diesel oil in our B/GT for several years. Available locally usually at a very good price.

https://rotella.shell.com/en_us/products/conventional-motor-oil/rotella-triple-protection.html

Cheers,

Larry C.
LC

Mobil 1 is far too thin for our engines - not even recommended by Mobil for the RV8.

IMHO any synthetic is a waste of money, the long service interval is negated by our rather dirty engines - far more cost effective to use a cheap 20/50 and change it every 3000 miles.
Chris at Octarine Services

Hi Larry, good to hear from you--hope all is well with you and your's
I reckom=n you're on a winner with Rotella, it's been a good oil for a long time--

I'm not much of a fan of full synthetic oils either Chris--although I guess they have their place but not in our cars-
-I run 0-30 synthetic in my golf cos i have to--If I put anything heavier in it the power drops off quite noticeably and you can't hear the turbo spooling up at all
William Revit

My Subaru Outback recommends 0-W/20 synthetic. That is fine for Northern -25C degree sub-zero temps in the winter. But here in the heat belt, I use 5W/30 due to our long 30C+ degree summer temps. I do oil changes at 5k intervals, not 7500 as the owners' manual suggests. I also notice the Subaru uses about a qt of oil between 5k changes. Other Subaru owners said the 0-w/20 seem to require a quart about every 2-3k. miles.

The MG gets 20/50 Castrol GTX every 3-4000 miles.
The parts store where I worked was bought out by another auto parts chain. Before we closed, I got 3 cases of of the 20/50 Castrol GTX @ $2.00/QT and a case of 12 Napa Gold oil filters @ $1.50 each.

Cheers

Gary
79 MGB
gary hansen

Gary
Quite a few of the later Subies use oil, caused by their low tension piston rings--not many would make it from service to service without a topup and the owners that don't check find out the hard way---and it's fairly common to have to do crankshaft jobs on them because of this
really important to keep the Subie.fuel aditve(injector cleaner) and manifold cleaner up to them each service otherwise the o2 sensors and cat. conv. get contaminated, specially if the car's doing shorter running

But I've got a feeling you know about this already
willy
William Revit

Willie: Your feeling is correct. The later Subies have seem to have gotten "better" with the oil consumption. My Outback is 2014.It has the PZEV engine.

Haven't heard too much about fuel injection issues. My mate has a 2009 Forester w/187,000 miles and I don't recall him talking about fuel injection system problems.



Cheers

Gary
79 MGB
gary hansen

Not so much an injection problem as such, but more to keep the o2 sensors and cat. clean with shorter running
(round town all the time), but if a car is doing it's fair share of mileage and getting up to temp regularly like your friends the issue lessens
Can't believe how many people here have been told, and sold that their Sub. needs a new front O2 sensor because the emissions light came on and threw a code for the catalyst system when all it needed was a good blast out the road
The later engines like yours are fairly good really apart from that nigling little oil leak from the timing cover on some--
Cheers
willy
William Revit

Follow this link to see a scientific comparison of an unopened can of 1950's oil to modern oil:

https://www.youtube.com/watch?v=-zHlxeu_yuM
Steven Rechter

Very interesting, and only figures, but interesting to see -

modern (API SN) oil - phosphorus 475 ppm (0.0475%) - zinc 581 ppm (0.0581%)
1950s mono-grade oil - phosphorus 475 ppm (0.0475%) - zinc 509 ppm (0.0509%)
Nigel Atkins

I started using Full synthetic oil 10/60 in the race mga twin cam engines as we had problems with the oil pump gears and cam buckets going over 7000 revs.Since then I use it in ALL my engines,included the prewar ones and motor bikes.
I had no special problems with oil leaks and certainly a lot less wear inside. No additives.
So far my personal experience.
Dirk
Dirk Van Ussel

This thread was discussed between 19/06/2020 and 11/08/2020

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