NB Front pulley isn't quite round.

[poison]

While having a poke and a play in the engine bay today, with the engine running I noticed my front pulley isn't perfectly round. Maybe 1-2mm off (hard to measure without risking amputation).

Is this harmful in any way? I can't imagine so, but thought I'd ask those in the know. It seems to be on nice and tight.

[Habanero666]

Hey there Poisonous one!

The possible reason this happened is because the rubber damper that separates the two sections of the pulley are maligned due to perishing/ hardening. Or the nose of the Crankshaft has FLOGGED out, I vaguely remember seeing a factory recall note on this for 1.8 engine.

I have seen this very often on certain french cars I used to work on, they sometimes throw the auxiliary drive belts! Now you don't want one of those going through the cambelt cover do we! nunganunga! oohlala!

Man, if it were my car I would flick that sucker and fit a new one! Which I have and they are not too expensive.

Now that I got your attention check out this link and see if it applies.

http://www.miata.net/garage/crankshaft.html


Jimbob

[Habanero666]

Actually the above only applies to 1990-93 1.8 engines so you should be sweet.

Get the pulley checked out because if the outer pulley runs off the inner it will give you probs!

[Ian]

Do you mean the 90-93 1.6 ????????engines?

Ian

[Habanero666]

HAHAHA True silly me!

[Growler]

In the thread title it says NB.
Infact it is only the very early ones that had the crank nose problems.
I believe Japan fixed the problem halfway through 1991.

The wobble could be just the allowable manufacturing tolerences from the factory.
You could take it off and machine it true if you really wanted to.