Way off-topic, but... 2-stroke engine fuelling question

406 V6 · Unread post by **406 V6** » 03 Feb 2006, 11:31

Hi chaps!

Can someone tell me if i can use petroleum (usually pink coloured myways, lamp use), on a modern 2-stroke engine?
I have an old sprayer we used to use for treating vines that starts on petrol, then we change it to petroleum for economical reasons.
As i say petroleum i could also say biodiesel,/veggie oil...

Thanks for any enlightenment!

BernieLugg · Unread post by **BernieLugg** » 03 Feb 2006, 12:58

Sounds like paraffin - I suppose there would in theory be no reason why not (so long as lubrication of the engine is taken care of via 2 stroke oil) but I imagine the engine would have to be hot hot hot before you could swap over - plus you would need to swap back prior to shutting down.

Many cars had a dual tank system fitted during & after WW2 and did indeed run on esso blue or Pratts pink - however this was in the days before electronic ignition, catatonic convertors and fuel injection. These modern engines may well be toasted by the use of paraffin.

Try it and let us know if it works

406 V6 · Unread post by **406 V6** » 03 Feb 2006, 13:42

Thanks Bernie!
When running on paraffin we used it pure, no oil addition was necessary.
Dang, the only 2-strokes we have now are a weed wacker and a cheap 75€ 800W gennie... Humm, how about a 4-stroker

? We have a 4KW gennie rarely used due to it's noise and the price of petrol.

bxbodger · Unread post by **bxbodger** » 03 Feb 2006, 13:48

Are you talking about running it on parrafin OR veggie oil?

It wouldn't run at all on veggie- the compression would be too low, and I don't suppose a tiny carb would be able to deal with it at all!!!

I can't see any problem with paraffin, though-even modern strokers are still pretty basic.

Kowalski · Unread post by **Kowalski** » 03 Feb 2006, 13:54

I don't think the octane rating of parafin (or TVO) will be high enough to run a modern car engine on but thats probably not a problem for a two stroke (baring in mind that they run on a two stroke oil mix).

Modern electronic ignition can cope with varying fuel qualities (engines with a knock sensor) and adjust timing advance and fuel mixture to compensate but there are limits. Some of the newer systems analyse the combustion via the spark plugs (they do it electronically). Saabs Trionic system was the first to do this and at the time it first came out it was advertised as being able to run on poor quality fuels, I suppose they'd advertise it as being able to run on parafin though. I don't think a petrol engine exists that will run on veg oil, not without mixing it with petrol and even then there would be a little bit more smoke than you're used to

bxbodger · Unread post by **bxbodger** » 03 Feb 2006, 14:44

Two strokes are still so crude that they are exempt from emissions testing anyway, so I don't think it matters what you lob in as long as its capable of being atomised by the carb.

I would imagine that a garden tool would still be petroil mix as well-probably no more advanced than an old villiers motor, there wouldn't be anything fancy like reed valves or oil injection!! Maybe electronic ignition, and that'd be it.

PowerLee · Unread post by **PowerLee** » 03 Feb 2006, 20:18

Be careful with the 2 stroke engine, Make sure the lubrication is looked after because they are wrecked very easily

I done a quote on a Stihl TS 400 disc cutter this week & it was a 2003 machine as well so not that old, Now to do the sort of damage to a Stihl 2 stroke engine that I found takes either loads of abuse of forgetting to use 2 stroke oil in the petrol.

The crank bearings where ruined, There was a few mm of play in them, So much so the flywheel was damaged where it had been hitting the ignition module as it had been spinning.

The piston had smacked the spark plug & closed the gap to nothing & the piston top had started to melt, In fact the piston had got so hot the aluminium it was made out of had changed, It was a different colour & was very brittle.

The cylinder & piston where also badly scored.

The quote for repair was nearly as much as a new machine, The boss of the company whos machine it was came in to see the damage for himself lol

Not a bad picture for a camera phone either

406 V6 · Unread post by **406 V6** » 03 Feb 2006, 21:15

Nice picture you've got there

Ok, petrol isn't "that" expensive anymore

(i just gotta quit looking at DIY generator websites, Petter diesels and stuff...lol)

PowerLee · Unread post by **PowerLee** » 04 Feb 2006, 15:20

Lister - Petter are the best diesel engines you could ask for in a generator

Got a 30 year old twin pot one at work & it always starts first swing of the handle

Kowalski · Unread post by **Kowalski** » 04 Feb 2006, 15:53

Lister / Petter diesel engines are the sort of engine that is so over engineered that it will last pretty much forever.

When my parents first built their house they didn't have mains electricity so they used a diesel generator with a Lister / Petter engine. They managed to break 2 crankshafts, some of that was caused by an alignment problem and the commutator not being in very good condition. After a commutator skim (bare in mind the generator set wasn't very new when they first got it) and 2 scrapyard engine bottom ends, the generator was fine and didnt do it again. That same generator is used as an emergency lighting standby generator now, it gets started and run up to speed once a week and has been doing that for the last 15 years or so.