NA 89-90 Vs 91 on 1.6L

Cruisin Newy · Postby **Cruisin Newy** » Sun Mar 29, 2009 5:42 pm

Hi all,

In my research of buying my first MX5 i would like to hear feedback on the short crank shaft vs long crank shaft.

I am hearing avoid the short but you would think this problem would have been resloved with originals and successfully motoring around with no problems. I am not a mechinical minded person but would like to see what people say and hopefully this either way help me decide on what one to buy as there is some nice early ones around at the moment.......

I have looked in past few weeks up to 1999 models and seen much variations in how MX5's have weathered by there owners and proberly missed out on few goods ones but that happens.

Hope to hear some feedback

Regards

Mark

StanTheMan · Postby **StanTheMan** » Sun Mar 29, 2009 6:27 pm

The short crank issue is there .......mostly because mechanics are not aware of it. & over tighten or undertighten the crank bolt. From 1991 onwards the problem was fixed.

I stressed about it to no end. Evetually replaced it with a JDM import engine.....& sold off my short nose engine. A number years later my engine block turned up in another car which was turboed......when I removed the engine it had done 193k km the key way of the crank in perfect condition.

so yes it is there If you are choosing between 2 identical car & 1 has the short nose of course then its a no brainer.

If you want to avoid it......just get the 91 onwards. Also check the crank pulley. The pulley for the long nose or fat nose does not fit onto the short nose. So just check to see which crank it has.....

bensale · Postby **bensale** » Sun Mar 29, 2009 8:43 pm

Keep in mind that the long nose engines are not immune to the problem either, there are a few people on here who have similar problems with this engine (1.6 & 1.8.) too. However, it is much more common on the short nose engine and many members on here have been bitten. If the engine has been maintained properly there should (although no guarantee as I found out) be no issues. However, as STM says

If you are choosing between 2 identical car & 1 has the short nose of course then its a no brainer.

I hate linking this thread but it has some great info in it viewtopic.php?f=18&t=32405&st=0&sk=t&sd=a&hilit=snc

Good luck on your search.

Cruisin Newy · Postby **Cruisin Newy** » Mon Mar 30, 2009 9:41 pm

Hi all,

Great Thread as i got dizzy looking at all the information discussions on the forum.......

I am still working on the one to buy and all the the info any one helps me with is very valuable. Im new to the motoring scene as prevoisly been involved in sailing etc for past 10 ys and always helped others in forums that may seek info....

At the moment im cleaning the garage out of old boating timbers & stuff setup for the boat to make way for a MX5 with the motoring posters(ok Girly Posters) Tool Board and even the Fridge, bar & bar stools even moving in to sit and admire the new toy. I know it must sound tragic but proberly many out there like this......... Will keep posted....

Cheers

Mark