1.6 crank pulley on NB motor woes
#1
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I started my car up this morning and it made an awful knocking sound. I was think "Great, another broken motor". But wait, there is hope. Its only the crankshaft pulley wobbling. I look down at it and there is only 1 M6 bolt holding the crank pulley on. The other 3 have disappeared.
I removed the pulley to find this:
![](https://www.miataturbo.net/attachments/general-miata-chat-9/39888-1-6-crank-pulley-nb-motor-woes-dsc_0643.jpg?dateline=1334094754)
I had to go look at the NB crank pulley and boss to find out why the bolt holes became ovals.
![](https://www.miataturbo.net/attachments/general-miata-chat-9/39889-1-6-crank-pulley-nb-motor-woes-dsc_0648.jpg?dateline=1334094754)
The crank pulley boss has an alignment pin in it, but my 1.6 boss does not.
![](https://www.miataturbo.net/attachments/general-miata-chat-9/39890-1-6-crank-pulley-nb-motor-woes-dsc_0646.jpg?dateline=1334094754)
Did it fall out? I know I studied both pulley setups to figure out what configuration I need to run the NB timing wheel with my 1.6 pulley. I can't remember if the 1.6 boss had an alignment pin in it or not.
What configuration do I need to run my 1.6 pulley with the NB timing wheel without things falling apart? Do I have to get a 1.8 alternator for the multirib pulley and then run the NB configuration?
I removed the pulley to find this:
![](https://www.miataturbo.net/attachments/general-miata-chat-9/39888-1-6-crank-pulley-nb-motor-woes-dsc_0643.jpg?dateline=1334094754)
I had to go look at the NB crank pulley and boss to find out why the bolt holes became ovals.
![](https://www.miataturbo.net/attachments/general-miata-chat-9/39889-1-6-crank-pulley-nb-motor-woes-dsc_0648.jpg?dateline=1334094754)
The crank pulley boss has an alignment pin in it, but my 1.6 boss does not.
![](https://www.miataturbo.net/attachments/general-miata-chat-9/39890-1-6-crank-pulley-nb-motor-woes-dsc_0646.jpg?dateline=1334094754)
Did it fall out? I know I studied both pulley setups to figure out what configuration I need to run the NB timing wheel with my 1.6 pulley. I can't remember if the 1.6 boss had an alignment pin in it or not.
What configuration do I need to run my 1.6 pulley with the NB timing wheel without things falling apart? Do I have to get a 1.8 alternator for the multirib pulley and then run the NB configuration?
#2
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Err, there's an alignment pin in everything you have, both bosses, both pulleys, why don't you shove the pin back in from your other boss get a new pulley without ovaled holes, and run that?
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I just Prime'd a 94-97 alternator. Going to run the full 1.8 pulley setup and not take any chances. I had no luck extracting the 1.8 alignment pin and don't want to fuxor it up.
Weird that it would fall out, no? That 1.6 pulley boss has ~150k on it.
Weird that it would fall out, no? That 1.6 pulley boss has ~150k on it.
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ARRRGH. The "1.6" pulley boss is actually the new 1.8 pulley boss with 89k miles on it. WTF!
If I were to use the real 1.6 pulley boss, my belt would be misaligned by ~2mm.
WTB NB crank pulley boss.
If I were to use the real 1.6 pulley boss, my belt would be misaligned by ~2mm.
WTB NB crank pulley boss.
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