OutdoorKing Repair Forum Forums Restoring, Customising and Modifying Tech Talk 2 Stroke oils, Mineral v synthetic

I mowed the lawn once while the greenies were having a meet in the local park - they were not happy

With regard to 4 strokes, I use regular car oil. I tend to use 15w40 cheap oil (the $8-10 per 5l on super special Gulf westerns or Nulon types) for a few mows after I get a mower. That strips the muck out.
After the few mows, I drain it and put in Magnatec 10w30 or GTX, or any other good 10w30.

However, I change the oil before it gets dirty - probably a good idea for the average person (who only changes it once every 2-3 years or more) to use the non detergent so the dirt remains at the bottom.
On that note, what ever happened to flushing oil? I got a bottle of Nulon engine flush for free, but haven't used it. Don't know what it might do.

I might try blending my Aldi Gardenline brand synthetic 2 stroke oil with some spare motor oil to make up my own cheap semi synthetic fuel mix.

Probably would do no harm MF. Because of the little amount I go through, I will just stick with the rip-off 2 stroke specific oil. Probably has no difference in the long run.
80ml left in the semi-synth bottle, should only be another month or so before I open the full synth.
I am betting no difference, but I have the guinea pigs to try it out on. These early cold winter nights, 6:30 pm with a led torch is perfect for seeing how much smoke comes out of victa exhausts.

G'day everyone,

I remember reading this post a while ago so I thought i'd post it here. This guy says he has ran his Victa Mustang on Castrol GTX and ron95 petrol for decades and it runs fine.

https://www.outdoorking-forum.com.au/forum/ubbthreads.php/topics/56799/2.html

I will keep using the mineral based Castrol 2 stroke self mix as i've been using it now for around 25 years or so.

I will probably switch over to synthetic 2 stroke oil when I can no longer buy the mineral based 2 stroke oil.

Cheers!

Hi there Converse,
good read from the golden era of Victa discussion (although we are experiencing a renaissance of sorts thankfully).

Just on the news that the majority of motor vehicles on the road get absolutely no benefit from using 95 or 98 fuel, claiming it is a complete waste of money and all these cars are far more sophisticated than a very basic design motor mower. So my belief is still that using 2 stroke oil only is designed to benefit the oil companies because they have been scamming the public since the year dot with all their marketing hype and now the proof is out there regarding fuels as well

G'day folks,
The potential issues with modern 4-stroke oils in 2-strokes are mainly due to the differing additive packs between the oil types.

Modern lube oils consist of a 'base oil' blend, plus various additives. Something like the 1950s Castrol XL had bugger all additives, in comparison to the current Castrol XL!

Without getting into the chemistry, modern 4-stroke oils can be up to 50% additives, to boost properties such as: anti-wear, detergency/dispersancy, anti-foam, anti-rust, viscosity index, anti-oxidation; to name the major ones.

Not all of these 4-stroke additives function as intended in a 2-stroke engine with its 'total loss lubrication', and they create three main potential problems;

1. Additives may not mix into, or remain dissolved in, petrol; they may also form gums
2. Some of them are metal-based, and will leave significant solid ash on burning, which can be abrasive and/or leave deposits in the combustion chamber - 2-stroke additives are ashless or low-ash.
3. Excessive smoke, as these oils are not designed to burn cleanly, unlike 2-stroke formulations

That said, it can be quite possible to get away with using some types of 4-stroke oil in low-output 2-strokes, such as mowers. I wouldn't use them in brushcutters or chainsaws, though.

And they're not advisable in any really high-performance 2-smokes, e.g. karts, motorbikes, outboards/jetskis, any Rotax engine, etc. Recipe for disaster, right there.

If you must do it, it'd actually be better to go for cheapo generic brand oils, as for sure they will have less additives in them, to save cost.

As far as 4-stroke mower oils go, the main reason for using SAE30 monograde in sidevalve engines [older Briggs etc] is just to minimise oil consumption. Multigrade oils are fine from the lubrication perspective, but in Oz, go for one with at least a SAE20 cold viscosity [i.e. 20Wxx].

As far as cost and low-end 2-stroke oils are concerned, there are two main reasons for their higher cost;
1. Economies of scale - car and truck engine oils are produced in vastly larger quantities - by far the dominant factor. And small retail packs are invariably the dearest option!
2. The additives that are used in 2-stroke oils are more expensive than those in 4-stroke oils, though this affects top-end products to a much greater extent.

Hi Gadge,
I hope you are not telling me not to use engine oil in my Stihl chainsaw I bought for $850 back in 1984, which was a lot of money back then and it is still in great working condition although I haven't used it for 12 months.

Hi Gadge,
do you mean pick 20W XX if you must use it for two strokes, or did you mean for the side valve four?

Penrite is on 30% special at super cheap this weekend

the full synth is $25 save $10

The semi synth is $11.64.

Super Cheap (and just about every other business under the sun) have that black friday sale this week

The best deal SCA have is Gulf Western Semi synth 2 stroke oil - 4l for $9.50. It meets JASO FC, and the price is definitely right

https://www.supercheapauto.com.au/p...z=60&start=8&prefv1=Gulf+Western .

Thanks Tyler, that is supercheap, I'm going to head off and get a couple of them and also see if I can use Jeans SCA card as well.

A pity, my local one at least, no longer stock Penrite 15w40 premium mineral motor oil. Semi synthetic only.
Superstupid.

Couldn't find it at the local store they had plenty on the shelves but at $31 I asked at the counter if they had any of the $9.50 ones and she said they were down the back.I went and had another look, still couldn't find it, had the 2 dogs in the car and it was hot so I had to give up on it

Norm, do what I do - click and collect and pick up next day or later in the week at a cooler time

Always have issues finding where the stock is at my local as well (and no staff will help), so free click and collect means those bludgers have to find it haha

MF, penrite 15w40 is 1/2 price $25 at repco this weekend - but its semi synthetic unfortunately

Thanks for the heads up Tyler. My local Repco normally stocks the mineral stuff. I hope that's included or did you mean they have it but it's not discounted?

Just checked MF, its semi synth only on special - will let you know if I see any 15w40 penrite mineral out cheap

If you would, thanks, even if it's Auto Barn. There is one a fair drive away. I'll just have to stock up.

Auto barn is also a fair drive away for me as well

I stocked up on the castrol ultra clean the other week - I now have about 40l of it sitting around

Will use probably 5l this week on some of my mowers

Norm, not quite so good a deal as before, but $13 for the 4L isn't too bad https://www.supercheapauto.com.au/p...oke-oil---4-litre/545139.html?cgid=SCA50 .

If you do a click and collect, they should have it at the front of the store for you so you can quickly pick it up and be on your way - I know the sort of weather you are having over there

They also have the penrite 5l bar oil for $17.5 which is ok considering repco were $42 last I checked