Petrol mix

[Andysp]

Hi,I have got a pole saw with an identical looking engine to this one but there are no labels or markings on it.Did some reading up on the net and this engine is fitted to a lot of those 5 and 1 tools.I'm trying to get the correct oil/petrol mix and I have read anything from 25/1 to 50/1.Does anyone know the correct mix and who makes the original engine?

[Ratman]

From Amazon, if you read description / spec at bottom of page it says 25:1 mix

 

 

[Ratman]

As for who makes em.... itchypitchu and aychinwaa in a shed somewhere in china town.

[Andysp]

Thank you for reply.The main reason I was trying to get correct mix is it takes a fair few pulls to get it to start and when it does start if I try to to give it full throttle it will try to rev up but then it starts to cut out.If I let go of accelerator it will keep running at idle.If I half choke it I can get it to full revs and after it runs for a while I can then get it to full revs but the problem can return when warm.

[Ratman]

Sounds like it wants a carb adjustment.

[scbk]

Most of the cheap Chinese engines say a 25:1 mix, but on a good quality oil 50:1 is fine.

[Andysp]

I'll go with the 25/1 and thanks again for a the help.

[Deafhead]

Try 30:1 as the more oil you put in the weaker the fuel air mix becomes. You might find that the pickup improves.

[spudulike]

This is like Groundhog day, the oil dictates the mix and not the engine. Most decent modern oils will run 50:1 and this engine will be fine on this mix.

To put it in to context - a 346XP will rev to 14700rpm and is fine on 50:1 so why should a cheap old lump of Chinese strimmer need more oil than that?

Yup, more oil means less fuel and air so it is running leaner but it isn't the normal conventional "lean" where the fuel/oil is replaced by AIR. You are replacing fuel and air with oil which at worst will carbon up the engine and may make it smoke and cough a bit.

Just run it on a decent oil 50:1 and if it still won't run right at the top end, turn the H screw anti clockwise whilst giving it full tilt and see if it improves, if it does, keep going until it starts coughing and then turn it clockwise until it JUST ABOUT CLEANS UP but not fully.

If it gets worse when doing the above, turn the H screw clockwise until the thing revs out better but make sure it doesn't scream, the carb H screw setting should stop the saw over revving.

[Ratman]

This is like Groundhog day, the oil dictates the mix and not the engine. Most decent modern oils will run 50:1 and this engine will be fine on this mix.
To put it in to context - a 346XP will rev to 14700rpm and is fine on 50:1 so why should a cheap old lump of Chinese strimmer need more oil than that?
Yup, more oil means less fuel and air so it is running leaner but it isn't the normal conventional "lean" where the fuel/oil is replaced by AIR. You are replacing fuel and air with oil which at worst will carbon up the engine and may make it smoke and cough a bit.
Just run it on a decent oil 50:1 and if it still won't run right at the top end, turn the H screw anti clockwise whilst giving it full tilt and see if it improves, if it does, keep going until it starts coughing and then turn it clockwise until it JUST ABOUT CLEANS UP but not fully.
If it gets worse when doing the above, turn the H screw clockwise until the thing revs out better but make sure it doesn't scream, the carb H screw setting should stop the saw over revving.

Can i get away with running my saws at 50:1?