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due to ill health and other problems the been stuck in the garage for nearly a year and now it won,t start. I haven't toched the engine since. I,m getting a nice spark and fuel getting through. I,ve heard that petrol goes stale after a while or is this a myth, it should at least try to fire.

Modern petrol certainly does go off. Wjhen I started my Sprint for the first time in 3 years last weekend. I put a couple of fresh gallons in, bled the fuel line through, about a pint. Emptied the float chambers using a sponge, checked the needle valves, made sure the pistons moved freely & cranked it over. It started second attempt.

This was after Rick (my brother) had been trying on & off for a month!

Also, don't be afraid to give it a whiff of Easystart just to get things moving at first.

Did you confirm spark at the plugs or just at the points?

The easy start may indeed help. A further screening test would be to dump a thimble of gasoline down the carburetor throat. If the engine starts, runs briefly, then dies, you have a fuel delivery problem.

As a footnote, you said that fuel is "getting through". Did you mean the fuel is being pumped to the carb or that you know fuel is in the float bowl? It is not unusual for fuel to build up gum and varnish deposits that could be holding the float valve closed. If it is an HS carb this can easily be checked by removing the float bowl lid to see if fuel is in the bowl. That gum and varnish can also build up on the mixture needle and jet and cause them to stick or limit fuel delivery.

I,m getting a spark at the plugs, and plugs have petrol on them.

I would say that you should get rid of the old fuel you have completely and stick some nice fresh Super Unleaded in. Modern fuel goes off very quickly and if left over winter will probably never fire.

Robert

dklawson wrote:

That gum and varnish can also build up on the mixture needle and jet
and cause them to stick or limit fuel delivery.

Yeps, seen it many times, especially if the old fuel had a bit of water in it .

Water settles below the fuel, so the fuel wont get it out of the little pipe from the float chamber.

Do as Mark wrote, and then put a cloth over the empty float chamber.
Then remove the piston, and blow down the jet, back into the float chamber.
You will be surprised to see what can sit inthere.
If the plugs are wet, spray them with brake cleaner, and crank the engine before refitting.
This way you push most of the fuel (water?) out of the bores.

madaboutcherry wrote:I,m getting a spark at the plugs, and plugs have petrol on them.

That might be your problem. Too much fuel on them. Dry the plugs out and try again. Put them in the oven and warm them up.
You could remove the fuel pipe from the carb block it off. Remove the float chamber lid, put some fresh fuel in the bowl, refit the dry plugs and try again.

If it starts re try with the old fuel through the carb. If it won't start, its your old fuel.

The wet plugs can also be a sign of a float valve that is stuck down/open.

My money is on the stale petrol. As others have said, it goes off very quickly nowadays.

I always add a gallon of fresh fuel in the tank before trying to start my Minis after even a couple of months laid up as they definitely start far easier with fresh fuel.

success. I cleaned the plugs, filled the float chamber with some fresh fuel, a bit of petrol into the carb and it started instantly. I was about to do a basil fawlty. anyway, many thanks for your advice, I,ve got to wait for a new float chamber gasket.

Glad you got sorted without too much trauma.