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shortnose had a smaller woodruff key and small bolt to keep everythingthing together. these were prone to wear, which would knock the timing out, rob power and worse - to avoid this problems, Mazda bulked it up for the long nose. Go for the longnose or keep a close eye on the shortnose.
 

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Long nose cranks are also not immune from similar problems.I read the link above several months ago and breathed a sigh of relief as it told me I have nothing to worry about with regards my wobbling pulley (1992 car - long nose), but it turns out that wasn't true at all.
 

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Not exactly true...

The car was launched with the LWSC (short nose) It's not the short keyway that causes damage it's the small nose and crank bolt with associated manufacturers torque setting that caused actual problems and issues with cars from the factory. Mazda performed a recall to an extent and fixed failed cars by replacing the crank with a revised "long nose" design. Later cars were then built with a big nose crank

The keyway has NOTHING to do with the integrity of the crank nose and it falling apart. Long/big nose crank noses wear when they have been inadequately torqued up usually after a timing belt service has been undertaken by a back street or DIY mechanic.

Any crank nose on any car will wear and eventually fail if it isn't torqued up correctly.

Luckily, big/long nose designs are usually easily fixable as they tend to only wear on the end of the keyway and crank nose lip. New crank pulley, acc pulley, crank bolt and key all torqued up correctly will have it all good.
 

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The nutzer formerly known as Fenix
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Discussion Starter · #6 ·
Thanks for the answers guys. So when was the switchover made? Any way of easily telling when looking at an engine which type it is? I take it this affects both 1.6 and 1.8 engines.
 

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The nutzer formerly known as Fenix
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Discussion Starter · #8 ·
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