i had the same problem on my cav 17td and i replaced the starter motor (with a used one) and it now starts better. i think there may be an underlying problem however with the valve clearances on this model which means that it takes longer for the engine to build up compression in order to fire up (especially when the engine is cold) that is why it takes about 20 or more attempts before it actually works. this obviously wears the starter motor out eventually.
you will probably get away with just replacing the starter for now as the weather is not so cold. however if you want to spend out the money on resetting the valve shimms it should sort out the problem more long-term, i.e for next winter/. this will probably cost around £100 if you can find somebody to do it.
good luck!
pw
March 2005
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