Allotment Gardening Advice Help Chat

Chatting => Equipment Shed => Topic started by: chickenboy on February 19, 2009, 13:11

Title: Quick two-stroke engine question...............
Post by: chickenboy on February 19, 2009, 13:11
I have a two-stroke generator that takes fuel/oil mix of 50:1, and a rotovator that takes the same mix ratio. My petrol strimmer, however, takes a fuel/oil ratio of 40:1, and I want to know if I can use the 50:1 in all three, to save mixing at different ratios, without causing damage to strimmer. This way, I can mix a batch of fuel for all three, in one container, without having to mess about.

Advice please!!.........................
Title: Re: Quick two-stroke engine question...............
Post by: Alfie on February 19, 2009, 13:35
The way you have to look at it your Generator and Rotovator take 50 parts petrol to 1 part oil

Your strimmer takes 40 parts petrol to 1 part oil.

Therefore the petrol for your strimmer needs to be oilier if that makes sense  :D

You could do damage to your strimmer running 50-1, it will run hotter and have less lubrication.
Title: Re: Quick two-stroke engine question...............
Post by: Gwiz on February 19, 2009, 15:39
I'f it t'were all mine, I'd run the whole lot on 40:1. :)
Title: Re: Quick two-stroke engine question...............
Post by: chickenboy on February 19, 2009, 15:48
Won't that eventually 'gum up' the 50:1 ratio engines though Gwiz? Are there specific problems with too much oil at those ratios?
Title: Re: Quick two-stroke engine question...............
Post by: Gwiz on February 19, 2009, 18:55
far better to use too much oil , than not enough!
It's true that it will be a teeny-weeny bit to rich in oil, but not by a great deal.
The guys at work tend to run most of their equipment with a bit too much oil, because they are using the stuff for many hours each day, they tend to get several years worth of domestic use in one season of professional use. all our seizures, are caused by overheating, and not by lack of oil (unless they do just put neat petrol in them by mistake)
you might find that the engines use a plug or two extra, over their life time, you might also find that they need their air filters changed/cleaned a little more regularly, and the worst case scenario, would be that it could need a decoke sooner., but it really does depend on how much you are using the equipment, what the equipment is, and where it was made........... (regarding machine life expectancy ;))
Title: Re: Quick two-stroke engine question...............
Post by: MoreWhisky on February 19, 2009, 19:27
make a 45:1 mix and use it in all three, the little bit of diference wont hurt anything. personally i guess my mixes anyway and never had any bother.
Title: Re: Quick two-stroke engine question...............
Post by: Bigbadfrankie on February 19, 2009, 20:48
I agree with gwiz use the 40:1 in all . I just Guess mine and fiddle with the carb  screws until they run well :D
Title: Re: Quick two-stroke engine question...............
Post by: chickenboy on February 19, 2009, 23:34
Thanks guys-food for thought!! :)
Title: Re: Quick two-stroke engine question...............
Post by: Diy-king on February 20, 2009, 07:04
I look at it this way, it is better to have a little bit more lubrication than less. Do you want it to seize or not.
Title: Re: Quick two-stroke engine question...............
Post by: Larkshall on February 20, 2009, 23:08
I look at it this way, it is better to have a little bit more lubrication than less. Do you want it to seize or not.

Many years ago (1950's) we had a top works rider in our Motor Cycle Club, used to ride for Greeves (anyone remember them?). They carried out a destruction test on one of their engines. It required the oil to be reduced in stages and the engine checked at at stage (remember this was for high performance two stroke engines). The destruct point was reached (seizure and damage) at 200 to 1 mixture. When I first rode a motor cycle Villers engines were using 16 to 1 and my Royal Enfield 125 used 24 to 1. I don't think the difference between 40 to 1 and 50 to 1 will have any problems.