Timing belt - how tight?

[wanand]

Hi, my timing belt light has come on at 140,000kms although I've had the belt changed at 100,000kms (don't know if the tensioner was changed tho). Done a search on the forum so I need to do a reset which is fine. Decided to take the cover off to have a look at the belt anyway and there was a lot of play in the belt.

How tight/tense should the timing belt be? Its def not as tight as say an alternator belt. If its too loose is there a risk of it jumping a tooth on the pulley?

Thx

[TonyN]

you don't say what motor you have, but they are all self tensioning, the 2.4 has a spring on the pulley, then you tighten a bolt up and lock the pulley in place, the 3.0's have a hydraulic piston that presses on the idler and keeps the belt the right tension.

[wanand]

its a gen 3

[michael sa]

Hi, my timing belt light has come on at 140,000kms..

It sounds like you've had a 60,000km odometer wind-back. (My light came on at 130K)

...look at the belt anyway and there was a lot of play in the belt...

From what I remember, (it's been almost 3 years since I did mine) - it's normal to be able to flex the belt. It should be quite tight on the tensioner side though.

If its too loose is there a risk of it jumping a tooth on the pulley?
Thx

If it's *too* loose, yes it could jump a tooth (or 10) But I think that'd only happen if the tensioner shat itself. I've not heard of a tensioner letting go in a 1KZT/-E

[NiftyNev]

Who did the belt? If you think it's loose then just reset the tension if you think the belt is ok.

Nev

[NiftyNev]

I've not heard of a tensioner letting go in a 1KZT/-E

How about the Idler.

http://www.toyotasurf.asn.au/forum/v...er+pulley+bolt

Nev

[michael sa]

Who did the belt? If you think it's loose then just reset the tension if you think the belt is ok.

Nev

It's hydraulic.

http://www.showmesome.info/hilux/inf...E/Page0160.htm

<edit>

How about the Idler.
http://www.toyotasurf.asn.au/forum/v...er+pulley+bolt
Nev

Yeah, read that thread ages ago. Different fault, with a similar net result...

[TonyN]

It's hydraulic.

http://www.showmesome.info/hilux/inf...E/Page0160.htm

He's talking about the timing GEARS, they run behind the cam belt housing and you can't get them without removing half the engine and its not something you need to get at unless rebuilding a motor.

Personally I think Nev is just trying to worry everyone with a 1KZ/TE as he has a 2.4 and is has 3.0 envy....... , its not an issue I've ever come across, and can't see how you'll ever break them without something else jamming in the gear train first.

[NiftyNev]

It's hydraulic.

http://www.showmesome.info/hilux/inf...E/Page0160.htm

Yeah I know but if the initial setup was done wrong then couldn't the belt be loose. Maybe the tensioner is stuck or the tensioner pulley is not pivoting correctly. Worth checking.

Nev

[NiftyNev]

He's talking about the timing GEARS, they run behind the cam belt housing and you can't get them without removing half the engine and its not something you need to get at unless rebuilding a motor.

No I'm not.

Personally I think Nev is just trying to worry everyone with a 1KZ/TE as he has a 2.4 and is has 3.0 envy....... , its not an issue I've ever come across, and can't see how you'll ever break them without something else jamming in the gear train first.

Yeah. Not heard of any problems with the idler for a couple of years now.

Nev