Timing Belt question

Blugg · Postby **Blugg** » Tue Nov 21, 2006 10:03 am

Hi fellas,

If my timing belt skipped a tooth, this means that the timing would somehow be advanced, and the engine would be pinging right?

I was driving up a steep hill one hot day, A/C on, passenger, and I could hear the periodic 'tack' sound like a marble hitting a metal plate. I was going WOT 4500rpm on 2nd or 3rd. I'm quite disturbed by this.

Other times, on second gear there's a slight pinging sound, sounds like 'clack clack clack'. The car is already 90,000kms and 8 yrs old, so perhaps it's time for a timing belt change? Any ideas?

It's an NB8A

Garry · Postby **Garry** » Tue Nov 21, 2006 10:09 am

I doubt the timing belt has slipped a tooth. You would be having other problems as well like poor performance and rough idle. Try a change of fuel brand or switch to a higher octane fuel, check your base timing and make sure you are using the correct heat range spark plug. You could also have a buildup of carbon in the combustion chamber.

Blugg · Postby **Blugg** » Tue Nov 21, 2006 10:10 am

Tried all that, have decarbonised, changed spark plugs, Shell 98, new coil packs. Idle is fine.
Only left are new engine leads.

Garry · Postby **Garry** » Tue Nov 21, 2006 10:13 am

dunno then

flycasta · Postby **flycasta** » Tue Nov 21, 2006 11:13 am

If your timing belt skipped a tooth the car would be running like a piece of crap. I have a Mazda/Ford courier ute and it pings on hot days as well. I think that the cars are very finely tuned these days and the temp combined with fuel and other atmospheric conditions can make them run lean which then makes them ping......that was what I got told by the Ford dealer when it had a tune last time.

Timing belts are a different story.....I sell gates brand timing belts along with a heap of other stuff as well and found out the other day that I shouldn't be selling any belts that have been on the shelf for more than 5 years. This is because under general use they would get changed every 5 or so years under normal 20,000 km's a year.

I would suggest to change your timing belt but make sure you keep a good record of when it was done, Km's and date so that nobody tries to replace it before it is due again. Gates belts come with a sticker to put under the bonnet which allows you to write a date and km's on it so everyone can see when it was last changed.

Duane

Boags · Postby **Boags** » Tue Nov 21, 2006 11:56 am

My intake cam was advanced a tooth when I bought the car and i noticed a drop in performance when I put it right...

It went like sh!t off a shovel before...

And rarely pinged on 91, went considerably better on 95/98 though. :?:

Boags