OutdoorKing Repair Forum Forums Restoring, Customising and Modifying Tech Talk 2 Stroke Synthetic Oils

G'day everyone,

I tried a search on 2 stroke oils and can't seem to find any previous threads on this subject.

Just wondering what you guys think about these newer synthetic and semi synthetic 2 stroke oils? Are they better?

I have only ever used old school mineral based 2 stroke oil and tend to steer clear of these new synthetic style oils. Mainly because I have stuck with mineral based 2 stroke oil and it's worked well for so many years now why should I go to a synthetic?

Now here's another thing I have been thinking about. I don't know if this will happen but I think there is a shift to these new synthetic based 2 stroke oils because it could be that they are more clean burning and emit less exhaust smoke. Well that's what i've been reading and also what I may have heard around the place.

What I am also thinking is possibly after July 1st this year, it could also be harder for oil companies to still produce and sell old school style 2 stroke oils that emit a fair bit of smoke etc. I am thinking that these new emission laws might also crack down on old dirty high smoke emitting 2 stroke oils.

That could be how they get what's left that still runs on 2 stroke to emit less smoke and pollution.

Well anyway i'm old school and I want to keep using good old mineral based 2 stroke oil. I think Castrol 2 stroke mix has been my chosen 2 stroke oil for around 25 years now. I think I will stock up on a few of the 1 litre self mix bottles while I still can...lol

Cheers!

Oil companies will continue to produce 2 stroke oil when they can charge a premium price for it compared to other oils on the shelf. The oil in a 2 stroke goes through the motor in the blink of a second compared to oil in a 4 stroke that is sometimes not changed for years. This oil needs to be a better quality because it can be full of contaminants and start to break down with time

Aldi sells 1l full synthetic 2 stroke bottles for only $12.99 in their special buys from time to time. Some posters here have claimed you can reduce ratio of oil to petrol this way, but not sure how much. 30:1 or 40 :1 perhaps? I think I'll just stick to the recommended 25:1 and let the mower enjoy the full benefits.

G'day everyone,

I have never used synthetic 2 stroke oil Mowerfreak. I don't know I just think when these engines were designed and made, they only used mineral based 2 stroke oils. I am also a bit skeptical on how much protection these synthetic oils really give. The only thing I can think of is they probably burn cleaner than the old school dinosaur oil..lol

I was walking through the Bunnings lawnmower section the other day and I think every bottle of 2 stroke oil on the shelf is some sort of synthetic mix. Nothing they stock is just plain old mineral based 2 stroke oil. Why is that? Bad for the environment? Or because it's actually better for making your 2 stroke engine last longer? Because we all know they don't want that!

Yes I always have this idea that the companies want you to use less 2 stroke oil to wear down your engine faster. I always stick to 25:1 mix and never go less. If anything I might add a tad more oil but never less.

Yep think i'll stick with classic mineral based 2 stroke oil at the original mixing ratio of 25:1.

Cheers!

I have been using synthetic 2 cycle oil for nearly 10 yrs now without problems. The particular one that I use is a Pro-Mix that is used in handhelds that operate anywhere from 50:1 to 16:1 and until recently actually mixed at 40:1 [3.2 oz to 1 US gallon], now it has been upgraded to a newer synthetic oil that mixes at 50:1 [2.6 oz to 1 US gallon]. This oil is nearly smokeless but in some older machines it still smokes.

Yes it was at first hard to trust that it provided that protection I needed since nearly 2C handheld I repair is for a customer. It does however cuts the number of fuel mixes sitting around going bad. It even contains a fuel stabilizer that greatly reduces ethanol separation; still a good idea to shake the can up but using the fuel if it been sitting a while.

It should be fine to mix it at 25:1 if you feel uncomfortable using it as a multi-mix though it might over-oil things.

It would be interesting to find out from someone that uses this oil in the larger 2 cycle engines as the biggest I used it in is the 70cc class chainsaws.

Never bought 2 stroke oil in my life, always just used whatever engine oil I had sitting here and usually it is the cheap stuff

Hi Norm and all
So just mix engine oil with unleaded in the right quantity eg 200ml to 5 L for 25/1 ? sounds good to me and save heaps of money ! When you check the oil requirements for 4 stroke outboards they say only use this or that but it was refreshing to see in my manual for the 90hp honda the oil requirement is 10W30 engine oil and not some specific marine grade bla bla. All about marketing and $, It should be remembered that the business of business is to make money.

Cheers
wce

What next, discarded fat from a deep fryer? I vaguely recall a Victa instruction booklet saying not to use multigrade oil as the mix as it will shorten engine life.
I bought a mark iv 125 cc and the owner claimed he had used synthetic 2 stroke oil and it certainly had grunt comparable to a 160cc going through thick grass.
I have read somewhere that 2 stroke for outboard boats is not good for garden equipment, due to high ash or something.

MF nothing wrong with deep fryer fat, quite a number of Enfields have been converted to run on that, bit smokey but run ok, bit slow but that is all you can get out a 300cc diesel concrete mixer motor
wce, I run all my 2 stroke stuff out of the same can, mowers,whippers,chain saws. My Stihl chainsaw I bought in 1983 still runs fine and my little $80 10 inch saw runs fine as well, as long as it has oil in the mix it keeps things lubed and as I said, the oil doesn't spend much time in there

Personally, I use Penrite 2 stroke oils. 1.5 years ago, there was the semi-synthetic 1l bottles out for $1 more than the 'greenskeeper' full mineral oil. Did notice less smoke, but don't know if all the things about preventing carbon build up under the rings is true. Semi-synth or not, they all seem to have about the same sulphated ash content, but the full synthetics have a lower flash point, meaning less smoke.

I have almost finished that bottle and recently bought the Penrite MC-2st full ester synthetic oil - $22 for 1 L - figured I might as well give it a go. If it can be used for highly stressed bikes, should be great for garden low compression 2 strokes. Same probably can't be said for the super high octane fuels they use.

However, 2 anecdotes:
A mate bought a GMC trimmer in 2003, runs the castrol self mix at 25-1, never serviced it, cleaned air filter twice, never checked or changed the plug. The coil was buggered last year, so I replaced it with another used one, did a full service. Replaced the plug, but the original cleaned up fine ( bearing in mind 1200 sqm block with lots of lawn fortnightly use), little carbon in the muffler, and only a little blow by down the piston. Runs great.

A previous neighbour only has the small lawn at the front of the house (to the point where starting the Victa was more an inconvenience than mowing). He told me he only sometimes added oil to the mix - and it was usually the left over canola or vege oil the missus had used in the kitchen (put through a strainer.

And then you see the well looked after engines that just go bang for no apparent reason...

Good morning all,

Great topic, I have used for a few years now Valvolene Marine 2 Stroke oil for air cooled engines. It was on special at Supercheap for around $22 for 4 litres. Used in my trimmer and all of my mowers. Especially good in the Victa Twin mixed at 25:1 for everything. I bought a new Rover/MTD blower at Christmas time and itcame with a small bottle of synthetic oil to mix at 40:1 and it seems fine but once out of warranty it will go onto the Valvolene as well. I think I will keep an eye on the catalogues and when it’s on special again I will stock up.

I don’t see why you could not just mix straight 30 weight oil with unleaded to run two strokes on but mind you it’s dearer than two stroke oil anyway. This looks reasonable from Supercheap Auto, might get a few of these for stock. Price looks good.

G'day folks,
Outboard oils aren't optimal for air-cooled 2-strokes, as they're formulated for the much lower running temps of once-through water-cooled outboards. Not to say that they won't work OK, but more carbon deposits are to be expected.

That said, back in the early 70s Mobilco used to recommend Castrol 'Super Outboard' oil for Echo 2-strokes, over their ordinary '2-stroke Oil' of the day.
Castrol Super TT superseded the Outboard oil for Echo gear, once it came on the market in the late 70's.
That one was essentially formulated for high performance two-stroke air-cooled motorcycle engines, and there were some quite large and powerful ones on the market at that time. The Kawasaki H4 750cc triple comes to mind...
Umm, bad idea.

Modern 4-stroke oils contain over half 'additives', unlike in the 1950's when Victa used to advise the use of 'Castrol XL' oil - which was then almost straight mineral base stock oil.
Some of these additives [e.g. the anti-wear and dispersant components] leave a significant solid 'ash' residue when burned, which will tend to clag things up in time. Also, these oils are not formulated to be miscible with petrol, and some of the additives won't stay mixed.

The synthetic 2-stroke oils do burn a lot cleaner, and can usually provide effective lubrication at much 'leaner' mix ratios.

IIRC the first synthetic 2-stroke oil that came on the Oz OPE market was the Optimol brand, introduced in the early 1980's by Canning & Son of Hawthorn, Vic. This stuff wasn't cheap on a $/L basis, but the ability to run 50:1 or leaner mix [which was unheard of with the mineral 2-stroke oils of the day] substantially offset that.

To run the very lean mix, it did need to be used with a carby with mixture adjustments [on OPE, these were the Tillotson, and later Walbro and Zama etc. diaphragm carbies], and this is still the case.

Varying the proportion of oil in the fuel mix does affect the fuel/air ratio going into the engine, so correction is required. All else being equal, leaner on oil = richer fuel/air ratio.

G'day everyone,

It's great to hear about all the types of different oils everyone has used as 2 stroke oil. I have heard many years ago of some people just using regular engine oil to mix for 2 stroke oil. But I just thought that they didn't want to spend money on proper 2 stroke oil and I also thought it wasn't all that good for the engine. But as NormK said, he's been using it for a long time now and it seems fine. Well who knows, even proper 2 stroke oil is probably just regular 30 weight oil with some coloured dye added in to make it look different and also so you know when you've mixed it with fuel.

When I was younger I just used to buy a little 200 ml bottle of 2 stroke oil from whatever servo I was getting 5 litres of unleaded fuel from. I have used Mobil, Shell, etc. But back in the day these were all mineral based 2 stroke oils.

Hi AVB, I think our local Bunnings hardware store chain here in Australia actually sells that 2 stroke oil you mentioned that has the fuel stabiliser included in the mix, I checked the label and it says it's made in the USA.

The only issue I have with using say vegetable oil, or any cooking oil in general, is how well does it actually mix in with unleaded? Then does it go through all the fuel filters and fine parts in the carby before finally reaching the engine? Also I don't know how good it really is at lubricating the internal engine parts. It's one thing to put a little bit of vegetable oil on a bicycle chain I remember doing that a few times when I was a kid. But I don't think i'd use it in the 2 stroke mix...lol

Tyler, I actually bought a bottle of the Penrite greenskeeper mineral based oil a while ago, the only reason I did was because the Castrol self mix bottle doesn't have the measuring marks on the side like they did years ago. I liked that the Penrite bottle has an easy to measure out bottle. But the thing I noticed with the Penrite greenskeeper oil is it actually smells a bit like your burning straight Penrite engine oil in the 2 stroke..lol Believe me after using Castrol self mix for so many years I can tell the difference in scent of the exhaust fumes when I went to Penrite. I think I actually prefer the scent of the burning Castrol self mix over the Penrite.

I have just finished all the 5 litres of the Penrite 2 stroke mix and my next mix will be back to Castrol 2T self mix again. Just a personal preference.

Cheers!

I did run my Monaro with a Chev in it on peanut oil once, smelt good but didn't last too long

Hi Members,

Thanks Gadge, this is a very good topic. Learning some good pointers here.

I wonder, did the Germans come up with any brand of 2 stroke mower engine? Like the Japanese, our cousins in sausage shop land had a high regard for 2 strokes I believe. You'd think they of all nations would develop their own. I believe Deutschland was one of Victa's export markets. Maybe they saw the mower engines from Australia and thought "even we can't better this" and decided to concentrate their energies on other projects lol.
They did have the quirky Trabant car, albeit from communist East Germany. They turned out to be quite reliable, albeit rudimentary.

Thanks Paul,
*cough* Here I have to declare I'm operating at a 'disadvantage', as compared to some of those who pontificate on some lubrication forums, tho' not ODK.

As in, being a technically qualified professional [Industrial Chemistry and Chemical Engineering]; with knowledge, interest and professional experience in the fields of Tribology [the science of machine lubrication], lubricant formulation, and used lubricant analysis for diagnosis of excessive wear...

Our Forum Historian CyberJack can confirm this, as he's seen a pic of my study 'certificate wall'...

BTW, NormK may have been referring to the use of used cooking oil as fuel in a diesel Enfield bike engine, not lube oil.

I do know that Enfield India Motorcycles did/do market a model with an industrial air-cooled diesel single-cylinder engine. They must be 'interesting' to ride; given the revs vs power/torque characteristics of this engine type...

Converse, be careful with the marks on the penrite bottles - the 20ml mark is more like 15. The semi-synthetic has no real pronounced smell - but on cold starts, there is a victa smoke plume through the garden.

Gadge, The Bio-diesel can make you hunger for french fries and deep fried turkey.

I can find the cooking oil on the roadside after Thanksgiving here. Just hard to get the lye to do the conversion here as the government is afraid we all are making crystal meth.

Hi Tyler,

Thanks for that mate, I did measure out 200 ml using the Penrite bottle a while ago. But I think I put in a little bit more oil just in case.

You know what I do now with the Castrol self mix, I have kept a small bottle of the 200ml self mix and I just pour the oil into this from the big bottle of self mix. At least you know your getting 200ml and a tad more every time. Much easier than trying to look at the lines on a measuring jug or something..lol

Yes I think the cold start up plume is just standard for a 2 stroke, no wonder the neighbours love me when the Victa 2 stroke starts. That reminds me I must stock up on good old dirty smoke plume mineral based 2 stroke oil so I can keep the neighbours happy for years to come...lol

Well one neighbour has a wood fireplace burning all of the winter months, the smell is that bad most of the day and night, the smell of smoke from the fireplace even gets into the house here during winter. It's like there is no escape, I think they get off easy having to listen to the Victa 2 stroke once every couple of months. Maybe I should mow the grass more often...lol

Cheers!

Hi Gadge yes the factory built the diesel Taurus, good going downhill but a bit slow on the uphill side. Heaps of others have been modified over the years to take a variety of diesel engines, but they all suffer from vibration damage. I worked on one some years ago that a bloke was riding around the world, he was about half way when he was in Aus. They are cheap to run but so slow

I often mix 40 mil of oil into a 1 litre former metho bottle for easier top up. My two stroke oil bottle has a precision chamber with a scale you squeeze the oil into through a built in tube.
That 200 mil bottle idea is a good one, as long as you use 25:1 equipment.

G'day folks,
Not so. While it does use the same mineral base stock oil, the additive package is completely different.

The 2-smoke synthetics aren't generally much better than mineral base, as far as good mixing and antiwear properties go, but generate less smoke and engine deposits, which is somewhat due to their leaner mix ratios.

Just as an aside, about the best oil to use in very high performance 2-stroke engines on the market is Castrol A747, which is castor oil based. Can only be used as a premix in the fuel, though; it's too viscous for oil injection systems.

Not at all cheap, but it saves having to do top end rebuilds more than once in a 'Forgotten Era' classic race bike comp season. That pays off big time now; these bits are getting scarce and exy, particularly barrel sets for TZ series Yamahas.

Vegetable cooking oils are not in any way suitable as engine lube oils, as they will form gums quite quickly. Castor oil isn't a cooking oil BTW!

Nowt wrong wi' that; it'll work just as well.

Germany produced some very high-tech 2-strokes, even unto a supercharged 2-stroke DKW race bike in the 1930's.

Dunno about push mower engines, but the ILO 2-stroke engine saw use on at least one Oz-assembled 1960's ride-on.
https://www.outdoorking-forum.com.au/forum/ubbthreads.php/topics/27325/
Edit: There were substantial tariff barriers to importation of small engines up until the mid 1970's, with the UK as the only favoured source in terms of concessions.
So I'd think it unlikely that any Euro engine imports for push mowers would have been an economically attractive proposition.
'Rudimentary' is being a bit kind to those cars! It was said that the reason they had a heated rear window, was so that your hands wouldn't freeze as you were pushing it... They now have collectable status, weirdly enough.

Saab also made a few early 1960's car models with 2-stroke engines; there was an immaculately restored 600cc one around Sale, Vic that I saw regularly when I worked there, about 10 years back.

There was actually also an Australian car that used a 2-stroke Villiers twin engine, the Lightburn Zeta....

I forget which one it was either the BSA Bantam or the Enfield Flying Flea was a direct copy of a German bike, only the thread size/pitch were changed to imperial sizes

Suzuki brought out small vans and 4WDs with Suzuki 2 stroke engines in the 1970s. The Japanese loved them in their home market, until emissions came into play. I rode in a Suzuki Carry van with this motor back in the 80s. it had so much torque up hills and sounded very sporty.
Here is one of a 4WD example.

Hi Guys,

Since we are discussing 2 stroke fuels I have to ask why isn't there an industry standard for the colour as I've seen Red, Green and Blue which I must admit for the uneducated can be quite confusing.

I was lucky enough to pick up a Kerbside Victa yesterday 30 seconds after it had just been put out complete with catcher and a half full fuel can which has red fuel in it, so from that I can safely say that this mower has not been straight fuelled at all and has probably just been parted with due to tenants moving out of a rental and into an apartment etc. that has no grass to mow.

So I have to once again ask why 3 different colours and not one standardised colour for two stroke oil ?

Cheers,
BB.

BB obviously there is no requirement for oil companies to comply to so they each do their own thing, the fact you have only seen 3 colours means there is probably only 3 of the bigger companies making 2 stroke oil

Go 1/2 blue and 1/2 red to make up a purple cocktail. Then you can intrigue your neighbours or girls passing on the street with your new hue showing through your weed wacker tank!

Or you may be able to just use food dye if you really wanted - I remember reading somewhere that many food dyes are somewhat petroleum based.

Although that could just be 'fake news' put together by some overprotective mothers group haha.

G'day folks,
True as far as it goes, but there are water-soluble and oil-soluble versions of the food dyes, and I've only ever encountered the water-soluble versions on retail sale.

That water solubility property can be used for an easy spot check for the presence of ethanol in a fuel sample, though.

A few drops into a say 20-50mL sample in a glass jar; if the colour settles in a droplet to the bottom - ethanol-free. If the colour disperses through the bulk liquid, it contains ethanol for sure.

I want a petrol with that bright fluorescent pink colour of the latest coolants you see. I'd dig that.