timing belt

[Navin]

hey all

Just wondering about the 5's timing belt.
I asked the bloke i bought the car from if he ever changed the timing belt.
He said that he changed it when he got the car in 2005 when there was 40,000 miles on it. It has 70,000 miles on it now so i would imagine it would have another 10,000/20,000 mile left in it.
But seeing as it was over 5 years ago since it was done, would it want to be done again now as its in so long, or would it be ok?
Also, would just changing the belt do or would the pulleys etc want to be changed too?

[leamyj]

If you're gonna strip out the front of the engine to change the timing belt then you may as well change the pulleys at the same time, you should consider replacing the water pump while you're in there too.

John

[jaffa20]

Is it not every 60k miles on the mx5? Mine has nearly 50k miles and is 8 years old. Don't think it was ever replaced. Isn't the mx5 a non interference engine?

[leamyj]

Preventive maintenance?

[Navin]

Was thinking may as well get the lot done while it was striped down. May as well do it now than doing it when its too late and i'm stuck on some back road with a broken timing belt!! I was told before though that the pistons don't drop if the timing belt snaps so all wouldn't be lost!!

[Navin]

Just read there that the timing belt should be changed every 60,000 miles or every ten years so I should be good for another 20,000 miles or five years!!!

[Steve]

oh its 10 years? Great, I've a couple in hand so, thought it was 5. I had one snap on me in 2003.

[Navin]

oh its 10 years? Great, I've a couple in hand so, thought it was 5. I had one snap on me in 2003.

Did it do any damage to the engine or was it ok?

[Steve]

still going strong, new belt and all was ok.

[gunners5]

I have done two timing belts now and find it an enjoyable job on a 5 as access and visability to the timing marks are great.Don't give the job too some muppet mechanic who will make a shite of it use a credible garage.
Most importantly establish what crank type you have as wrong torque settings on a shortnose crank can ruin the engine.
Shortnose=4 slots on the crank pulley.
Longnose=8 slots on the crank pulley.

[TOM 5252]

I got my timing belt changed last Friday, by the mechanic who was working in the Mazda garage where I bought my Mk2 12 years ago, and has since set up his own garage.
One tip he mentioned that I thought I should pass on, is that when we got to the point of fitting the new tension spring that came in the MX5Parts kit he fitted it without the rubber sleeve that it comes with, because otherMazdaa cars have had problems with this sleeve splitting over time and dropping down and damaging the belt or making it skip a tooth. Theoriginall spring and sleeve we removed looked fine but why take the chance since the sleeve, if it is there for protecting the spring, doesn't cover the whole spring anyway when it is fitted andstretchedd.
The belt we removed showed no signs of wear ofatigueue, it was jusstretcheded a little after 39000 miles and 12 years. The other 2 belts were also like new and were re-used, The car has always been kept in a closed shed, which I think contributes to the freshness of the 12 year old belts.

[TOM 5252]

PS

Apology--
The strange words above are the result of using " ieSpell " for spell checking, I never seen it doing this when used previously. I should have checked it after I had spellchecked it.


becomes previousy ---becomes---- becomepreviouslyiousy

[Fergus]

Only read this post now, I've never heard or read online of that 'rubber sleeve' failing and falling off so I'm wonder where your mechanic got his information as it's nowhere online.
Yet another 'urban legend' I think as that sleeve has a groove in it for wear/heat/usage etc etc.

But hey, if your car's going good then don't fix it
(if it's not broken then don't fix it)

(PS) Err that rubber sleeve can also act as a heatshield for the spring itself as it's not just made of 'rubber/plastic' and it's right at the front of the block. If the tensioner spring itself fails due to excessive heat failure then......yes, the cams will skip. But hey, it won't do any damage to the engine at all, it just means you'll have to bring it back to your mechanic again and he'll make more money from you WHEN THE FIRST TIMING BELT CHANGE HE DID MUST LAST 60,000 MILES/48 MONTHS IF IT'S A Mk1 MINIMUM


(edit) so how long will that metal spring last without any shielding....that depends on your milage - will you drive 60,000 miles in 48 months ? I think not. Will that spring fail in 48 months ? Perhaps not even if it's a daily driver. I mean, Mazda thinks people drive Mx5s at the most 60,000 miles in 10 years. Case Closed.

[Steve]

After the tension is set and you've tightened the pulley bolt, you could just remove the spring and keep it till the next time you are changing your belt. The pulley doesn't move once tightened down so the spring isn't needed.

I think Tom's mechanic might have been talking about this