Which engine oil for a quick top-up.

[Iyarno]

I haven't had my 68' +2 for long, and I've only done a couple of trip so far. However, during a routine check at the weekend I noticed the oil level was just below FILL.

Can anyone advise which oil I should use as a safe 'top-up and go' until I get round to doing a complete change in the near future. Unfortunatly I have no idea what was in there to start with.

Thanks all,

Ian

50/0632

[andyelan]

Hi Ian

As you don't know how long the current oil has been in the car, for the amount of time it would take, I'd simply drain the sump replace the filter and refill with a reasonable quality 20W-50 mineral oil.

Regards
Andy

[Iyarno]

You're right, I'm being lazy. I already have the passenger door in pieces while I try to service the lock mech and I was trying to avoid taking on too many jobs at once. It's all still very new to me.

Anyway a new filter is ordered and I was thinking of getting the Halfords Classic 20W50 for now. I've read about Millers on here, but there aren't any suppliers near me. Is there any reason to make the extra effort to go for that? Or can I get away with a more regular 15W40?

Ian

[richardcox_lotus]

There are a million and one threads on here about "which oil" ? but i have used halfraud's 20-50 Mineral before for short periods - seemed fine. Note I've never mixed it with Synthetics & am currently using Castrols' Classic 20-50 range. (Looks more authentic on the garage floor)

Regards
Richard

[andyelan]

Hi Again

I too use Halford's Classic 20-50 in my Plus 2 and have found it fine for normal road use.

Andy

[Esprit2]

Did you check the oil level hot? It will give a slightly lower reading when cold.

When you select an oil to use, make sure it contains a high level of ZDDP as appropriate for a flat tappet cam. Viscosity and ZDDP are important. After that, you have some lattitude to play favorites.

Regards
Tim Engel

[69S4]

Did you check the oil level hot? It will give a slightly lower reading when cold.

When you select an oil to use, make sure it contains a high level of ZDDP as appropriate for a flat tappet cam. Viscosity and ZDDP are important.

I've always assumed it would be the opposite and that it would show lower down the dipstick when hot as some of the oil would be distributed elsewhere in the engine. Leaving it until cold - overnight for example - would give time for as much as is going to to drain into the sump.

The complexity of the oil market seems to have gone beyond reason in recent times. Some oils have this or that in it, some don't - and the only way to tell whether you can use it or not in a particular engine is by deciphering the hieroglyphs on the back of the can. The resulting paranoia about whether you've bought the right stuff has lead me to wondering whether it's safer to leave the old oil in there rather than refill it with the wrong spec. It's even worse on one of my flat tappet motorcycles where the wrong choice will not only wear out the cam train but will also cause the clutch to slip.

I also use the Halfords Classic 20-50 in the Elan. I've no idea whether it contains zinc or any other ingredient but their marketing info seems to suggest it's suitable and nothing appears to have worn out after a few years of use.

[Esprit2]

Stuart,

Things expand when heated, and contract when cooled. You're right that some oil will be pumped out of the sump when the engine runs. But if you drive the car until the engine is thoroughly up to temp (not just starting to feel hot to the touch sitting in the garage), then switch off and then give it 5 or so minutes for the oil to drain back down from the upper portions of the engine, that will give you the most accurate oil level reading. Then let it sit overnight and check the oil level while cold in the morning. That will give you some idea of the difference between cold and hot readings for future reference.

Some engine's have cold and hot marks on the oil dipstick... at least observe them.

The complexity of the oil market seems to have gone beyond reason in recent times. Some oils have this or that in it, some don't - and the only way to tell whether you can use it or not in a particular engine is by deciphering the hieroglyphs on the back of the can.

Yeah, the oil market has become a bit of a mine field for the consumer, and the hieroglyphs don't cover ZDDP content. The confusing ratings might be okay-necessary if they would at least provide a map, but they don't. The current API SM low-ZDDP "Green" standard targets only four multi-weight viscosities that must be "green" (cat converter friendly low-phosphorus), 0W-20, 5W-20, 5W-30 & 10W-30. Those oils must restrict ZDDP to 600-800 ppm while our flat tappet cam engines should have 1000+ ppm minimum, with 1200-1300ppm being more comfortable.

All other viscosity grades "may" use more ZDDP, but they're not mandated to use a standardized level. That opens the door for oil companies to blend products with very high ZDDP levels, or down to the 600ppm minimum and label them all with the same API SM certification. Is their corporate policy to present themselves in as Green of a light as possible, or is it one of dominance in high performance motorsports oils. The resulting oils can be very, very different and still fall within the extremely broad wording of API SM. And nothing on the label tells the consumer anything about the product's ZDDP level or how appropriate it is for use in a vintage flat tappet cam engine.

"Trust us, we know how to blend oil". Probably true. But is their goal for the oil the same as that of vintage car owners and motorsports enthusiasts? In many cases, no.

The resulting paranoia about whether you've bought the right stuff has lead me to wondering whether it's safer to leave the old oil in there rather than refill it with the wrong spec.

NO! leaving the old oil in the engine is not a valid option. Contaminants, including acids, build up in the oil with use, and they can't be allowed to remain in the engine. Also, some of the required additives are consumed with use and old oil may not provide the required level of protection any longer. It's important that you change the oil regularly, and you must make the effort to identify which oils are safe for use in vintage flat tappet cam engines.

It's even worse on one of my flat tappet motorcycles where the wrong choice will not only wear out the cam train but will also cause the clutch to slip.

The API SM restrictions on ZDDP do not apply to motorcycle oils, which produces a few options for vintage car owners. There are very high ZDDP oils available at retail if you just shop in the motorcycle aisle. The old Mobil 1 20W-50 that Lotus recommended way back when (early 907 days) contained 1600p-1700z ppm of ZDDP. That level exceeds the API's current upper limit, so Mobil 1 20W-50 could no longer be sold as an API rated oil. Rather than sell it without the rating (as Redline and Amsoil do), Mobil dropped it. Well, sorta. At least in North America, the product was re-branded as 20W-50 V-Twin Motorcycle Oil. It's the same great stuff, Hi-ZDDP with full street additives, it's just in a different package in a different aisle. Vintage car guys have a good synthetic option.

True racing oils are expected to be changed after every race event, so they leave out the street additive package. If you run such an oil on the street, then it should be changed every 500 miles/ 3 months, which ever comes first.

Some oil companies that want to provide high performance oils to vintage and motorsports enthusiasts, but don't want to lose their API certification in a mainline brand, are adding full street additive packages to their off-the-shelf racing oils. That's a way of giving enthusiasts back-door access to hi-ZDDP oils for their specialty cars in street use, but the oils are still marketed as "racing" oils and "not recommended for street use" (NNWWSNM... keeps API happy) with no direct mention of their street capability.

If you know which racing oils contain full street additive packages (Mobil 1), then you might consider using them in your vintage or hi-performance, flat tappet cam engine like you would a normal street oil. If you don't know if a certain "racing" oil contains street additives, then use a very short oil change interval... like 3 months/ 500 miles, whichever comes first.

In North America:
Mobil 1 0W-30 & 0W-50 Racing Oils (1750-1850 ppm ZDDP) and Castrol GT Racing Oil (Castrol doesn't divulge ZDDP levels) contain full STREET additive packages.

Valvoline "Not Street Legal" Racing Oil (1300-1400 ppm ZDDP) does NOT contain street additives, and Valvoline recommends changing it every 3 months/ 500 miles, whichever comes first.

Valvoline also has three other VR1 racing oils (one other mineral oil, and two synthetics) (1200-1300 ppm ZDDP), but I don't know if they have full street additive packages.

In North America, Mobil 1 15W50 contains 1200-1300 ppm ZDDP as their token mainline street performance, sorta-high ZDDP oil. All other Mobil 1 products contain 800-1000 ppm, depending upon the grade. We should view that as uncomfortably low for our Lotus engines. http://tinyurl.com/2scbb7

I also use the Halfords Classic 20-50 in the Elan. I've no idea whether it contains zinc or any other ingredient but their marketing info seems to suggest it's suitable and nothing appears to have worn out after a few years of use.

I'm in the USA and Halfords isn't sold here, so I don't know anything about it. It might be great stuff, and one might presume a product named "CLASSIC 20W-50" would be formulated to take care of vintage engines; but if not, oil company guarantees cover the cost of the oil, not the cost of rebuilding your engine. The only person covering your backside is you. It wouldn't hurt for a UK volunteer to contact a Halford's tech service rep to find out what the ZDDP content is in ppm (parts per million) and report back here. Don't accept "adequate" as an answer.

Regards,
Tim Engel
Lotus Cars Oftha North (LOON)

[paddy]

I'm in the USA and Halfords isn't sold here, so I don't know anything about it. It might be great stuff, and one might presume a product named "CLASSIC 20W-50" would be formulated to take care of vintage engines; but if not, oil company guarantees cover the cost of the oil, not the cost of rebuilding your engine. The only person covering your backside is you. It wouldn't hurt for a UK volunteer to contact a Halford's tech service rep to find out what the ZDDP content is in ppm (parts per million) and report back here. Don't accept "adequate" as an answer.

The Halfords site says:

SPECIFICATION OF HALFORDS CLASSIC OIL 20W50

API SE CC
Protects and preserves old engines
High viscosity helps to reduce oil loss & leakage
Multi-grade Oil for use in Summer and Winter
Oil adapts to outside temperature
NB. Recommended oil change every 2000 to 3000 miles

I can't find more useful/definitive information online, yet.

Paddy

[Esprit2]

The Halfords site says:

SPECIFICATION OF HALFORDS CLASSIC OIL 20W50

API SE CC
(Snip)...

SE... wow, that goes back a ways. They were probably still squeezing oil out of dinosaurs by hand when that came out.

Regards,
Tim Engel
Lotus Owners Oftha North (LOON)

[69S4]

Tim, thanks for the comprehensive reply. Unless you type at ten times the speed I do I can appreciate the time it would take to do that. Some of my comments were a little tongue in cheek - particularly the bit about sticking with the gloop already in there, but it does come from a genuine confusion about the way the oil market has gone in recent times and the difficulties of finding the "least worst" oil for a particular engine. Atm we have eight vehicles here (not counting lawn mowers etc!) and they all require different spec oil. Trying to find out which can is suitable for what in my local retailers can take hours.

A couple of weeks ago I was changing the oil in our diesel Land Rover and went to buy some from our local LR specialists. The staff there ended up arguing amongst themselves over which was the correct spec! You might say what the hell do they know beyond how to process your card but this is a well respected company employing mature (as opposed to minimum wage) enthusiast staff and a mainstream (for a LR!) engine. If it's a problem somewhere like that you've no chance at some of the "pile it high, sell it cheap(ish)" places like Halfords.

The zinc additive info is something I've only ever come across from sources on your side of the pond. Over here it seems to be completely off the radar. Presumably it's in some formulations and not in others in the same way as it is in the US but if I hadn't heard about it from people like yourself I'd never have known anything about it / what it does / why I need it. Paddy's quote of the Halfords 20/50 spec is about all we get. Does that stuff look like it's got ZDDP in it? Should it if they're targeting it at twink era engines or is it only suitable for pushrod tech engines like the old BMC A series?

Back in the day the same stuff went into just about every engine whether side valve, pushrod or flat tappet but now there seems to be an oil for every occasion and an atmosphere of fear promising an automotive apocalypse if you get it wrong. If I didn't know better I'd think it was the marketing men trying to frighten you back into the hands of the main dealers, where you can relax in the knowledge that an expert technician will resolve all of these troubling issues for you.

[Galwaylotus]

I haven't had my 68' +2 for long, and I've only done a couple of trip so far. However, during a routine check at the weekend I noticed the oil level was just below FILL.

I checked the accuracy of my car's dipstick by checking it after a complete drain and fill - including filter. I put in almost the prescribed amount of oil then started and warmed up the engine thoroughly. When it had been shut down for a little while I checked the level on the dipstick and found it to be "high". That probably explains why I was losing pressure on right turns when the level showed anything less than Full! My point is that to check your car's oil level you should probably do the same.

[Esprit2]

The zinc additive info is something I've only ever come across from sources on your side of the pond. Over here it seems to be completely off the radar. Presumably it's in some formulations and not in others in the same way as it is in the US but if I hadn't heard about it from people like yourself I'd never have known anything about it / what it does / why I need it.

Stuart,
The problem did seem to get more attention first on this side of the pond. It's possible the oil here took a dive first since the API SM standard is pretty broad for oil grades other than the 4 or 5 specific ones that are mandated to be "Green", so perhaps Euro SM oils maintained a higher ZDDP level longer. I don't know.

Here, ZDDP was cut down to the new "green" limit of 800 ppm by pretty much all the major oil companies (ignoring specialists like Redline) without so much as a hint of an announcement. And they didn't just cut down the few mandated green grades and leave the rest alone, they cut across the board. It didn't come to light until vintage and hotrod engines began to experience a rash of accelerated wear related failures. Actually, I think the problem first came to light with a number of Britcar owner clubs, British-Leyland products, Austin Healey, MG, Triumph, etc...

A public outcry went up, and some oil companies responded, but not all. Exxon-Mobil, for instance, had cut all the Mobil 1 grades down to 800 ppm. Now a couple of grades are up a little to 900-1000 ppm, and 15W50 is the one token performance grade (ignoring the Racing Oils) with 1200 ppm phosphorus/ 1300 ppm zinc. But that's still down from were it was before the cut, and most Mobil 1 grades are still down at 800 ppm.

Without disclosure on the package label, the consumer just needs to know which brands and grades are safe to use in their older engines. Most companies don't publish ZDDP data. You can't pry it out of Castrol for love nor money. Valvoline talks about it but doesn't publish anything where it's easy to find. If you're persistant, you can find limited ZDDP info on their website. The nice thing about Mobil 1 is that they've posted a product spreadsheet on their website that tells what's in each product... very helpful.

Again, the crux of the problem is the lack of set API standards for ZDDP content in the API SM standard, and the oil companies not taking responsibility for informing their customers in the absence of a published standard.

Paddy's quote of the Halfords 20/50 spec is about all we get. Does that stuff look like it's got ZDDP in it? Should it if they're targeting it at twink era engines or is it only suitable for pushrod tech engines like the old BMC A series?

Nothing in the specs Paddy posted says anything about ZDDP level. That's the big problem from a comsumer's point of view. Most companies don't publish ZDDP levels, and the API SM standard doesn't set specific levels other than for the grades mandated to be "green" (600min, 800 max ppm... way lower than our engines require). Other grades "may" use more, but that doesn't say they must or set a standard for how much. Some do, some don't, some a little, some a lot. You figure it out.

An oil formulated for older engines and flat tappet cams should have a ZDDP level of 1000 ppm as a minimum, and preferably 1200p-1300z ppm, IMHO. More if you use the car for track days, motorsports, or just hard driving. In short, yes, such an oil should contain more than the "green" levels of ZDDP. From what I've read recently on the Halfords website, they talk about it, but don't say anything specific.

Q: Does Halfords Classic contain ZDDP?
A: Yes.

Not helpful. All modern motor oils contain ZDDP.
:-\
The question is how much. Get a tech rep at Halfords (or any oil company) to state how much ZDDP and post that info here. That would be helpful.

Regards,
Tim Engel

[elansprint71]

Splendid thread.

[fatboyoz]

Penrite oils are available in the UK. Their Classic oils have higher levels of ZDDP.
http://www.penriteoil.co.uk/
http://www.penriteoil.com.au/index.php
http://www.penriteoil.com.au/products/c ... oils_light
http://www.penriteoil.com.au/pis_pdfs/C ... 202010.pdf

You could also try this product to increase ZDDP levels in any oil.
http://www.zddplus.com/
http://www.burtonpower.com/parts-by-cat ... ?brand=432

ZDDPlus is also available on the internet and can be posted through the mail.

Colin.