Having recently taken over as chairman of our plots I have the weighty responsibility of being custodian of the plot lawnmower which is a Yamaha M-120-X. I am going to use unleaded petrol, but not sure if it should be 95 or 97 octane? Also the last chairman thinks the 2 stroke mis is 25-1, i.e. 25 parts petrol to one part oil, can anyone else confirm this or tell me where i could find out online?

Thanks
Compo

Hi Compo
I would always use the lower octane petrol as it is not necessary to use top grade.
25:1 mix is a widely used ratio, try it on that if it emits too much smoke from the exhaust cut back to say 30:1. You can use some of the modern synthetic 2 stroke oils which are 'low smoke' and can be used at 40:1 and even 50:1 in certain engines.

Good luck
Hortiman

Thanks will try that 25:1 at first.

Compo

So I tried the fuel mix and it fired ok eventually but the engine keeps hunting high and low revs and if it hits long grass at a low point it packs up, any ideas how to adjust ? repair ? Although it is a Yamaha it is on a 'Hayterette' body.

The previous custodian (it is an allotment lawnmower) said it is designed to do this, but I smell 'b..ls..t' any ideas?

Compo

Yamaha lawmowers...didn't realise they imported them to the U.K....Are you sure it is 2-stroke?

Aha a Hayterette..You could try http://www.hayter.co.uk and email them for help..Sounds like a V. old machine if it really is 2-stroke.

Compo, there's loads of references to a Suzuki M-120-X 2-stroke. I wonder if it is rebadged Yamaha?

It looks likea refurb job with a hayterette chassis, maybe the engine was added later?

I'm not familiar with things Yamaha or Suzuki....but purely out of interest one model of Hayterette, Professional model 254, was specified with a Suzuki 2 stroke engine..not sure for how long..but it was listed in 1989.
At a similar time, and totally unrelated, Yamaha mowers were being sold in UK.

Hayterettes are excellent sturdy mowers and even though this example may be made up of an engine from elsewhere it may still be worth consulting a local garden machinery agent to bring it up to full health...if it continues to act poorly.

A local machinery agent may be able to recognise the engine and thus advise on the mix to use also...I seem to think we used to have a reference booklet, supplied by one of the oil companies, that we kept by the counter that gave 2 stroke mixing details for most makes of machinery...I have to admit though sometimes it was a bit like spark plug guide books..often the machine that the customer asked about was the only one not listed

Clive.

You are all right!! it is a Suzuki!!!
I'm dyslexic!!!

Sorry

Compo

The mix is 50:1 then.

Indeed they are Clive, mine, bought new by my father is on its second engine, second rear discharge flap/cover and second blade. The original disc with four swinging blades rusted off it's hub, so my neighbour bought me the single bar blade at a discount from work (guess where ),
The solid aluminium deck is brilliant.