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Hey guys, lately the car has been emitting a strange whirring noise which has been getting progressively louder.

At a novice inspection of the harmonic balancer I noticed a bit of play and wobble which has got me very worried.
From what I've researched the visual symptoms fit the snc issue however there's no noticeable loss of low rpm power or torque.

Unsure if it is actually a SNC issue or whether the belts have had it causing it to do this,(timing belt slightly frayed), or if it is anything else, ie water pump and snc together. I was under the impression the previous owner had done the 200,000km timing belt service however there's no documentation (208xxx kms now).
Have hardly been driving it and since the roof was slashed its been living in the garage yet it's gotten worse.

Additionally I can't find any info with the whirring noise coinciding with the snc. Perhaps they're 2 completely different problems? I'm not sure, which is why I'm posting I guess.

I've included a video, any help or feedback would be appreciated.

http://youtu.be/ECqLQRHwklw

Thanks, Doug

Just to further clarify for those who will be assisting you troubleshoot the problem, are you 100% sure that your motor is a SNC version (aka 4 slots on the pulley, VIN < 209446 etc) ?

I will go and check the vin now, but it doesn't have an Australian VIN as it's a 1990 Eunos Roadster V Special. I'm presuming it is the short nose motor.

Edit, it is a Japanese VIN 6A9SECREP97NPN002.

Hi.
When you check for wobble look from the side not front on. Wobble from the side yes you have a problem.

Wobble = probable nose problem. It doesn't matter if it's short nose or long nose, they can both get it. It's just more frequent in the old short nose.

Yours looks like early symptoms and hopefully fixable with the loctite repair. You need to get the timing belt pulley off to be sure.

Thanks for the prompt replies. It will be inspected properly tomorrow.

Does anyone have any ideas regarding the whirring high pitched noise that increases with rpm, even when stationary?

Alternator. water pump, PS pump or A/C compressor?

Doug Danger wrote:lately the car has been emitting a strange whirring noise which has been getting progressively louder.

Additionally I can't find any info with the whirring noise coinciding with the snc.

Doug Danger wrote:Does anyone have any ideas regarding the whirring high pitched noise that increases with rpm, even when stationary?

My old '89 NA6 made a whiring sound the morning of the day SNC struck. That was in Canberra & I had to drive to Sydney for a meeting. SNC struck that arvo at Campbelltown on the return to Canberra, so about 400km later. Fortunately it was recoverable - Liverpool Mazda sorted it & did timing belt & water pump as it had done 90k odd kms.

The whirring might be vibration in the belts caused by the wobbling of the pulley that drives them, as 93_clubman found with his car. Otherwise there could be a second problem, probably as JBT said with alternator, water pump, PS pump or A/C compressor. You'll disconnect all the drive belts to get to the timing belt pulley and that gives you the opportunity to feel for bearing noise in each of those ancillaries.