Page 1 of 1

Starting, Running and stuff

Posted: Tue May 27, 2008 8:58 pm
by zippy500
Any ideas please.

Having real probs starting and running my mog.

I have tried to play with the mixture screw using the lift pin method.

Once started, seems to idle ok, I getting problems when I am going mainly, there seem to be a at low revs a flat spot, almost choking on its self, then taking off.

What should the fast idle be with full choke on?(mines about 900rpm)

Its got a new dizzy, plugs, point checked and re checked timming but still no good.

Cheers

starting

Posted: Tue May 27, 2008 9:47 pm
by Willie
I am sure that you know that the mixture adjusting nut should be screwed right UPWARDS and then turned down by 12 FLATS. This should give you a basic mixture setting. You would then check that,with the choke OFF the jet is fully upwards i.e. there is about 1/4" of free play before the choke cable starts to move the jet itself downwards. If the weather is warm you only need a slight amount of choke to start from cold and should need none at all when the engine is warm. You should also remove the air filter assembly and lift the piston as high as it will go and then let it drop, it should fall with a soft plop. Make sure there is oil in the top of the dashpot otherwise you will get dreadful flatspots. Those are the basics, try them and let us know what happens. To explain the choke cable adjustment, there should be about 1/16" free play after which the throttle should be opened progressively by the next 3/16" of
movement WITHOUT MOVING THE JET DOWNWARDS. This raises the tickover without supplying a richer mixture. Further pull on the choke cable will then enrich the mixture for cold starting.

Posted: Tue May 27, 2008 10:25 pm
by zippy500
Thanks Willie,

Will try to "reset" the carb and see how I get on

Posted: Wed May 28, 2008 7:41 pm
by bmcecosse
Is the engine in good condition ? Any chance of running a compression check - and have you reset the valve gaps?
Could be petrol level too low - or could simply be that the choke is not coming on properly. But as Willie says - sticking carb piston is high on the list of suspects here!