Thanks gentlemen. Have got enough sawing done to continue with the mower...
It is the same as the S600 illustrated in the parts section, though the baseplate [what I'd call the deck - the cast aluminium body] doesn't feature the maltese cross type form in the centre.
Its missing one of the long springs CH84933A, and a clamp from the back axle. I'm inclined not to replace the spring cos removing the cover above the blades looks very troublesome with eroded bolt heads, or free spinning bolts. Is a grinder the tool in such situations?
Back to the carby. The O ring looks good, no blockages either, gasket behaved well. Theres no clip for the governor spring. I'll check the shop. With fitting the governor the instructions are to " Place the large gear in position with one tooth showing to the right hand side of the top of the small gear" The best I can manage is having the teeth about 50/50 on each side of the top of the small gear. Is that ok?
Havn't got to retest it as the pull cord recoil has packed a sad, and didn't have the time to tackle that can of worms.
Am I right that its of little value to try starting with a rope on the drum above the flywheel, as the governor need the cowling in place.
thanks - Alistair
