Aha cheers for the reply Fred...I think your machine may have been 'modified' in some way, as normally the central bolt holds the wheel in place, and once its been yanked off a square key ensures the wheel actually turns with the axle....there's no circlip with this particular model and there is a bolt in each axle. Anyway all is not lost because even if the wheel refuses to come off, you can inject a tyre sealant through the tyre valve, and once blown up the hole in the tyre will be sealed...believe me it works and I do this as a matter of course. All horticultural machine shops stock this stuff, it costs around £5 per wheel. Press on with the WD40 though - I've experienced some of these wheels being absurdly rusted in place!
Good luck with it!
John
August 2009
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