Whirring sound - disappears with clutch pressed

broady · Postby **broady** » Wed Nov 11, 2009 6:31 pm

Hi guys,

I've had a peculiar whirring sound, mostly when cruising at 2k rpm. I think it's the accessory belt but not certain.

Just now, when I pulled into the garage, I could barely hear it on idle (sitting in neutral), but it disappeared as soon as I tapped the clutch in a bit.

Any ideas?

broady · Postby **broady** » Wed Nov 11, 2009 9:22 pm

AJ says it's the throwout bearing. Thanks mate :mrgreen:

broady · Postby **broady** » Wed Nov 11, 2009 9:36 pm

For reference, the fix: http://miata.net/garage/tsb/s003_95.html

Will probably give it a go next week sometime.

Description

A light squealing noise may be heard when the clutch is out and the vehicle is at idle. The noise is not heard when the clutch is depressed.

This noise may be caused by insufficient grease between the clutch release fork and the release cylinder. To eliminate this problem:

the specified grease has changed from lithium to moly white grease
the configuration of the release cylinder push rod is redesigned to retain grease in the joint area.
A repair procedure for customer complaints is listed below.

Repair Procedure

Confirm the location of the noise. If noise is not heard when the clutch pedal is depressed, proceed to step 2. If the noise is constant, refer to the workshop manual for troubleshooting and repair information.
Apply moly white grease in the joint area of the release fork.
NOTE: It is NOT necessary to change the clutch release cylinder push rod.
Assemble and confirm repair.

manga_blue · Postby **manga_blue** » Wed Nov 11, 2009 10:13 pm

May also indicate failing front main gearbox bearing.

Fatty · Postby **Fatty** » Wed Nov 11, 2009 10:20 pm

my car had this same noise, it got very loud and then after a few months the gearbox shat itself and i had to replace it. i agree the noise you are hearin is most likely a bearing - if i were you i'd be sorting it out before it goes boom like mine did.

Hi 5 · Postby **Hi 5** » Thu Nov 12, 2009 8:59 am

If you're going to change the thrust bearing,change the spigot or pilot bearing as well.

RawSouth · Postby **RawSouth** » Thu Nov 12, 2009 9:18 am

My NB8B currently does the same thing, but it’s intermittent.

It used to be constant, so I took it to mania to get the clutch changed about 6 months ago. They told me that they replaced all the relevant bearings. I’ve only put on about 3,000kms on the car since then and now it’s starting to come back.

With all this talk of exploding gearboxes, I’m starting to get a little worried :S Especially as the 6 speed boxes are pretty damn hard to find!

Any thoughts?

broady · Postby **broady** » Thu Nov 12, 2009 9:53 am

Yeah mine is quite intermittent too.

I'm thinking of taking it to IS Motor Racing or MX5Mania to get a 2nd opinion.

RawSouth · Postby **RawSouth** » Thu Nov 12, 2009 10:02 am

I just hate intermittent problems.

Its just my luck that when I take it to the mechanic, it will be fine while its there, and then begin to squeek as soon as im home.

How are ISMR? Ive never used them, but they are quite close to home.

broady · Postby **broady** » Thu Nov 12, 2009 10:06 am

RawSouth wrote:I just hate intermittent problems.

Its just my luck that when I take it to the mechanic, it will be fine while its there, and then begin to squeek as soon as im home.

How are ISMR? Ive never used them, but they are quite close to home.

They're not close to my home at all, but I hear Indy's really good.

Mr Morlock · Postby **Mr Morlock** » Thu Nov 12, 2009 12:23 pm

If it is the throwout bearing it may continue like this for a long time without a problem. Most problems tend to be the more obvious things so if it goes away with pressure on the clutch pedal then this is the likely culprit and not the gearbox. Fault finding often takes the route of replace the suspected item and getting to the gearbox and or clutch is not a cheap exercise.

broady · Postby **broady** » Thu Nov 12, 2009 12:27 pm

Mr Morlock wrote:If it is the throwout bearing it may continue like this for a long time without a problem. Most problems tend to be the more obvious things so if it goes away with pressure on the clutch pedal then this is the likely culprit and not the gearbox. Fault finding often takes the route of replace the suspected item and getting to the gearbox and or clutch is not a cheap exercise.

Yep thanks, AJ pretty much told me this as well so I'm not too concerned although I'll definitely try to grease it up to stop the noise. It's been bugging me.

More pertinent issue is an oil patch I saw on the garage floor this morning... Bah!