MG-Cars.com
MG MGB Technical Is diesel oil better? BBS discussion at MG-Cars.net
MG-Cars.net
Welcome to our resource for MG Car Information.
Recommendations
Parts
MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.
|
|
MG MGB Technical - Is diesel oil better?
| There is a thread on the midget and Sprite board now on the extreme wear on cams and followers caused by the latest specification motor oil in our classic engines. http://www2.mgcars.org.uk/cgi-bin/gen5?runprog=mgbbs&mode=thread&access=&subject=97&source=T&thread=20061009022558843 One solution seems to be diesel oil, because it has more zinc and phosphate. But are there any possible disadvantages using diesel oil in a petrol engine? Tore |
| Tore |
| Of course I mean motor oil specified for diesel engines. Not diesel fuel. This language is sometimes difficult... Tore |
| Tore |
| Tore - I read an article several years ago in Car and Driver about the best oil for older cars and the author advocated the same thing, oil designated for diesel engines. Coupled with the article that you linked, I am seriously considering switching to diesel rated oil for our MGs. Cheers - Dave |
| David DuBois |
| A few comparisons Rotella Calcium 2884 Magnesium 10 Phosphorus 1164 Zinc 1311 Mobile 1 R Calcium 3024 Magnesium 13 Phosphorus 1399 Zinc 1536 Moly 78 Redline Calcium 4015 Phosphorus 1790 Zinc 2014 Molybdenum 961 |
| Paul Wiley |
| What kind of Redline oil is that, Paul? |
| Tore |
| Redlines oils all have a very similar add pack apart from Race that has few detergents and not suitable for road use. As ester based there is no need for visc improvers. SM oils need to pass the Sequence IIIG test using a pushrod pig-iron engine equipped with flat tappets of circa 1986 configuration. This was intentionally done to eliminate all concerns with valvetrain wear in older engines. Even the Japanese manufacturers who initially raised the concern agreed. http://www.swri.org/4org/d08/GasTests/IIIGtest/default.htm |
| Paul Wiley |
| Paul - can you restate that in plain english and tell us if all the oils or ok - sorry I have no idea what SM oils are |
| J Delk |
| In theory even low "Zinc/Phosphorus"(ZDDP) oils are tested and safe to use in older engines. However oil companies if not forced to reduce zinc use higher levels. This may be because its cheap or just works better than anything else especially in older engines. Given a choice, which we still have, I prefer the comfort of a higher Zinc level. The following is from Penrite An engine oil that contains about 0.1% phosphorus or higher, will easily provide the required anti wear properties for older engines. The step from API SH to API SL was accomplished by a combination of new additives or adding additional anti wear and anti oxidant to existing blends. These were not phosphorus based, but used organic molybdenum additives (not molybdenum disulphide - aftermarket oil additive), to keep phosphorus levels at 0.1%. Now we have API SM – for the first time, the limit on phosphorus is from 0.06-0.08%. There are industry concerns about the applicability of these oils in older engines. However, the limit only applies to 0W-20, 0W-30, 5W-20, 5W-30 and 10W-30 oils (so called “ILSAC” grades). Any other grades are exempt from this. Therefore even blanket statements about API SM oils will be incorrect and further research will be needed by the end user. There is one other factor with non-ILSAC oil grades. If they also have the European ACEA A2/A3 with B2/B3 or B4 performance levels, phosphorus levels will also be at 0.10 % to 0.12% as their tests have been more severe than the API for some time. Hence an oil that is SL (SM)/CF/A3/B3 also well exceeds the anti-wear requirements for older engines. The irony is that API SF and SG oils formulated in recent years usually have phosphorus contents of around 0.08% (usually 0.1% maximum) anyway due to other advances in technology, unless the blender chooses to add extra additive. |
| Paul Wiley |
| So the trouble in the USA may come from the use of oil that is API SM, but not ACEA A3/B3 or B4, and possibly not specified for diesel engines? And if I stick to oil that is both SJ/SL, and ACEA A3/B3 or B4 I may feel reasonably safe? Perhaps I should buy 3-4 years consumption right now! |
| Tore |
| That's really helpful Paul. Do I understand that Penrite 20w-50 SM oil is still going to have all the goodness in it? I have just built up an engine with a new cam and tappets and, having experienced rapid tappet wear previously, I'm wondering which oil is best to use? As I've also got to bed in piston rings, is running-in oil going to wreck the tappets? Are there any honest additives on the shelves of motor factors that can be used to improve things? |
| Steve Postins |
| Steve The indication is that break in is the big issue, rather than normal running http://www.joegibbsracingoil.com/news/060316b.php http://www.hotrod.com/techarticles/engine/flat_tappet_cam_tech/index.html Millers have a specific break in oil and may be worth contacting to see if they would dislose Zinc level. Oil companies do not readily disclose any information, although the Penrite site is better than most. Not keen on additives but certainly the Joe Gibbs break in oil is 3000ppm. |
| Paul |
| For those who are concerned about running Diesel oils, this might be something to consider. I worked at a Mercedes-Benz dealership in the mid-1990s or so -- right after the "new"-style 300D and 300E came out (the W124 body for those of you who know Benzes). The 300E (M103) gasoline engine had a significant oil consumption problem. MB first put new valve stem seals on under warranty, and when that didn't work they started replacing pistons with specially-sized replacements (again under warranty). It didn't help, so in desperation they recommended that Shell Rotella be used in all M103 engines. That's about the time I left the dealership so I don't know if it solved the oil consumption problem, but I'd say that that's at least a stamp of approval for Rotella in gas engines. I just bought a TD, and I think I'll run Rotella in it..... FWIW. |
| Rob Edwards |
| Back in the 60s air cooled Porsches were often run on diesel engine oils once they were run in. I think this was more to do with the increased detergencey they theory being they would see the owner out under this regime. Oils have come a long way since then of course. Just propmted by the MB story, the W123 4 pot engines had an oil consumption problem here in the UK where memories of the long stroke HP tax engines meant they were not revved and the oil control rings did not get bedded. |
| Stan Best |
| I forwarded some of these concerns to my 'tech guy' at Amsoil. Hopefully, soon I will be able to share what they have to say. Hey Robb, I worked for Benz dealers from 1972 to 1985. Only saw a few of the early 'new' cars. SF Dwight |
| DCM McCullough |
| Looking for a cheap fix I stopped off at Halford's yesterday and saw two products. STP Oil Treatment for Petrol Engines states that it is a bumper pack of additives of the sort already found in oils, but doesn't give details. Does anyone know? Less helpful is a new Halford's own-brand 20w-50 Classic oil, "formulated like original oils from the classic car era". Priced just above their own 15w-50 and packaged in on old style tin it's #1 technical claim is that "it's green, like oils used to be". #2 is that it contains seal-swelling compounds to reduce leaks. I'm not quite convinced it's the way forward. |
| Steve Postins |
| Will take a Std oil to ZDDP levels of Diesel oil. High mileage oils will tend to slightly higher visc a tadge more ZDDP and extra seal conditioner. Likely to more a GI base oil rather than GII. |
| Paul |
| It'll be interesting to hear what Amsoil says. My question was going to be does a synthetic oil substitute alleviate the problem in any way? |
| Joe Ullman |
| I blasted an email to STP and got this reply: "The STP Oil Treatment will add Zddp or zincdialkyldithiophosphate to your oil. It has almost 4 times the amount of anti-wear agents than most motor oils contain. I would recommend this product for your engine. We do not recommend that you use it in a diesel engine." Do I assume the last comment is because diesel oils already have high levels of ZDDP and you can have too much of a good thing? |
| Steve Postins |
| So STP recommends STP - wow! As an infamous person said in the 70s "Well they would say that, wouldn't they". I'm guided by the common sense (to me) approach that says if any additive was better oil companies (for anything other than a very budget product) would already include it. Likewise if Diesel oil were better for classic engines. But then I'm a cynic. My Son once said his ambition was to be as cynical as me ... but I don't know whether he was being cynical or not. |
| Paul Hunt 2 |
| Point taken Paul, but like many others I've experienced horribly rapid tappet wear in recent times, having taken great care to break the cam in properly. I've even gone to the lengths of using various different followers for a few thousand miles at a time but with very mixed results (pictures available). I've got two new cams to install over the next few of months so am looking for some insurance, even at the risk of reconsidering what I've previously though of as snake-oil solutions. |
| Steve Postins |
| The oil companies would still use zinc, as it is a cheap anti wear agent, but US legislation has mandated reduced zinc and phosphorus levels because they are requiring catalytic convertors to last 150,000 miles. Diesel oils will have the reduced levels next year, it even says so on Rotella's site, and it's because of new diesel regs. Some synthetics and racing oils such as Valvoline's VR1 still have the higher levels of zinc. |
| Greg Bowman |
| Steve - I'd be tempted to blame poor quality of the followers. I've not used any additives in the roadster over the 16 years and 45k miles I've had it, and haven't needed to adjust the valve clearances since I started adjusting them at the point of maximum gap rather than the strict 'rule of nine' point. I've mentioned before that trying to do them at the recognised point gave very variable results, even turning the engine one complete revolution and rechecking the ones I'd just adjusted. Someone else has recently posted that GTX, for example, has a significantly different formulation in the US to the UK, presumably to meet local regulation in the US. Whereas the UK has at least three formulations I understand the US only has one. This could well account for differences opposite sides of the pond. |
| Paul Hunt 2 |
| Valvoline Racing 20W50 states right on the container that it has ZDDP. |
| Robert Dougherty |
| You may well be right. The guys in the links at the top of thread certainly seem to have their suspicions about the followers as well as the oil. At Chris Betson's suggestion I'm only using Piper's own followers now and with those and some appropriate oil I'm keeping my fingers crossed that this time they might last as long as your set. |
| Steve Postins |
| Motor oils contain ZDDP apart from Fuchs Titan GT1 0W20 which is used in Porsche Cup Racing. It is only low viscosity new SM oils "energy conserving" that have reduced ZDDP and they still pass the above test. ZDDP is multi purpose not just an anti wear additive. Mixed zincs are used because they decompose at different temperatures. Primary zincs start to decompose around 184-186 degrees F while secondary zincs decompose at higher temperatures thus providing antiwear protection across a broad temperature range. ZDDP will start to decompose at high temperatures. |
| Paul Wiley |
| Should add pressure gives increase in localised temp. |
| Paul Wiley |
| Castrol GTX 20W50 no longer lists ZDDP (Zinc) as an ingredient on the MDS sheet... |
| Robert Dougherty |
| Includes ZDDP http://safetydatasheets.bp.com/ussds/amersdsf.nsf/0/217B4D9572D0669D862571060034D0D0/$file/Castrol%20GTX%20Mileage%20Motor%20Oil%20English%20(US)%20US.pdf |
| Paul Wiley |
| Anything new from Amsoil, Dwight? Tore |
| Tore |
| Hello, What about theses new high mileage oil on the market. I bought some from Castrol but do not know if it is sanke oil... Cheers, JGC |
| J.G.CATFORD |
| Castrol GTX for 'high mileage engines' in the UK is close to the original GTX, although 15W/40 instead of 15W/50 and before that 20W/50. What is 'sanke'? |
| Paul Hunt 2 |
| From a Castrol data sheet, some time ago it appeared that the ZDDP is greater in HM than GTX. Also, VI and viscosities are higher in the HM oils, but the HTHS rate value was worse. ZDDP is also an anti oxidant and corrosion inhibitor as well as anti wear. However, looking at Maxlife the only difference appears to be moly is added and calcium increased. The claims for Valvoline MaxLife is that it helps condition seals and prevent leaks, reduce oil consumption and reduce deposit formation. Not a "snake" oil and judging from anecdotal evidence does appear to help. |
| Paul Wiley |
| Sorry Paul, I meant "snake oil"... JGC |
| Jean Guy Catford |
| So far, this is all I have. Check it out. SF Dwight https://www.amsoil.com/lit/databulletins/g2245_rev8_06.pdf |
| DCM McCullough |
| As a matter if interest [or not!] Duckhams 20/50 was cheaply and easily available round here until quite recently, now it has disappeared off the shelves, one shop keeper told me he had stopped stocking it due to a large hike in the price? Ron |
| R. Algie |
| Just for the record: Comma Sonic 20w50 has 0.14% zinc. Just mailed the company and asked them. This oil should be easily available in the UK, and is here in Norway, too. Statoil ClassicWay has 0.15%, but that is probably available only in Ireland and the Scandinavian countries? Tore |
| Tore |
| Ron, I bought a can of Duckhams 20/50 in April for £8.99. I tried to replace it last month- £12.99- same shop! I went elsewhere- £13.99! I noticed that it now has the word "Classic" on the front........ |
| Martin Layton |
| Anyone aware of a company that sells an additive that's meant to supply the lost ingredients? |
| Joe Ullman |
| Joe As in US Try SX UP - worth emailing your concerns and see what answer you get http://specialtyformulations.netfirms.com/store/nfoscomm/catalog/product_info.php?products_id=37&osCsid=610dea42b1ceb251fc7b1273fe0dc2cc |
| Paul Wiley |
| STP states on the container that it has more ZDDP than competing brands, they don't tell you how much ZDDP it has though. Clifton |
| Clifton Gordon |
| Clifton STP is likely to have enough ZDDP to raise a std oil to HDEO level, but will be basic compared to SX UP (see below). However price wise a HDEO or race/road oil will probably be cheaper option. SX-UP than just these elements. As per our PDS, we also use many ashless organic compounds (not shown on elemental analysis, of course) and agents such as rust inhibitors, Friction Modifiers, Anti-Oxidants, viscosity index improvers, surfactants, metal deactivators for copper (copper corrosion inhibitors), detergents, dispersants, etc. The base oils are PAO's and esters ("Quad-Esters"). Anything less than 10 ppm was ignored. Molybdenum - 1400 ppm (Friction Reduction, AW, AO) Boron - 500 ppm (AW, FM) Tin - 12 (AW) Phosphorus - 1500 (AW) Zinc - 2900 (AW) Calcium - 4200 (Detergent, AW, FM) Magnesium - 250 (Detergent) Silicon - 8 (Anti-foamant) TBN 19.3 KV @100 C - 16.5 This product was originally developed for engine oils in muscle and classic cars from approx. 1955 to about 1980 in order to boost the additive levels of current SF/SH oils to approx. API SD equivalent AW status. The original SD oils had ZDDP levels approximately equivalent to today's HDEO oils. |
| Paul Wiley |
| Just a thought...we jave not experienced follower wear since we switched to billet cams and stopped using repro ones. We still use the same followers. The A series cams come with oil feed holes on the ramp of each cam lobe.I put a blob of moly assembly paste on the face of each follower before fitment. Running in the cam properly is essential. With regard to oil...I was having my Harley MOT'd recently and noticed the Putoline oil for Vee engines....formulated for slow revving pushrod engines....I reckon this will be great in the older MG engines...price looked pretty good too. Peter |
| peter burgess |
| Here is the tech bulletin from Amsoil-------------- https://www.amsoil.com/dealer/techservicesbulletin/TSB_flat_tappet_and_camshaft_lube.pdf But you do have to open it up and read it---------------- SF Dwight |
| DCM McCullough |
This thread was discussed between 10/10/2006 and 03/11/2006
MG MGB Technical index
This thread is from the archive. The Live MG MGB Technical BBS is active now.