Broken Timing Belt Confirmed

[Kigiin]

I'm at 96k on my second belt, suspect I have plenty of time.

By guess is that the belt did not break.

 

[Muddy Bean]

thrillseeker here...subscribed.

 

[80Greg100]

Subbed as well...Mine was done by PO at 64K miles, back in 2009 I think. At 108K miles now.

 

[twentyocho]

Did the one on my 4Runner (also 4.7L) at 140K.. Still looked good. Im guessing alot to do with where you live and the conditions you put your truck through..

 

[Copenhagen1]

Updates??

Inquiring minds want to know......

Sent from my iPhone using IH8MUD

 

[Supra88]

130,000 miles - original belt after 12 years:

 

[2000UZJ]

FYI- my timing belt looked brand new. 140,000 miles (hard miles), and cooling issues. Some days my engine would run 250*F water temps. Normal driving temp was 220*F.

 

[profro]

I just bought a 2000 with 212k miles on it. The previous owner had never done the belt and he bought it when it had 74k on it. I immediately took it in and had the belt, pulleys and tensioners done.

 

[OGBeno]

6 days no update.

 

[bamachem]

I once did a 3.4L 5VZ-FE belt at 168k and it was fine. The belt I did on a 2000 UZJ at 100k looked like new.

 

[Supra88]

I will say that as bad as my belt looked, structurally (the core of the belt) it appeared to be fine.

 

[marques]

Two more data points: 1st timing belt replacement at 7 years/110,000 miles - old belt looked fine, didn't replace anything else. 2nd timing belt done recently at 14 years/220,000 miles - old belt looked fine also, this time also replaced all the pulleys/tensioner/water pump.

 

[jgray]

Sorry guys life has been crazy busy lately. Here are some pictures to start my update. More to follow...

A few of the broken timing belt...

 

[OGBeno]

Wow.

Thanks for posting up.

What is the situation with the engine currently?

 

[jgray]

Aside from the broken timing belt there appears to be no further damage at this time. Heads look good and the belt broke due to timing tensioner failure... Tensioner failed most likely due to my own fault of wheeling the crap out of the Cruiser for many years. Here's a few engine bay shots after heads were pulled (showroom condition right?! - haha)...













More to follow...

 

[hoser]

How many miles/years on the tensioner?

 

[OregonLC]

Tensioner failed most likely due to my own fault of wheeling the **** out of the Cruiser for many years.

Not likely. If that were the case then every gasser middle east and OZ LC would have broken belts. Heck, Nick would have gone through three broken belts by now! Engine load shouldn't affect the belt life. Or do you mean prolonged water exposure? Any chance your cover plate was left off on a previous t-belt job?

And by 'tensioner failed' do you mean it developed slop or that it over-tightened? Trying to figure out how it could be the latter?

Lastly, we have two cases now where a broken belt had no collateral damage. How sure are we that this is an interference motor?

 

[spressomon]

Well...at least you solved the question of whether or not the 2UZ-FE is an interference engine or not. Good to hear there was no ancillary damage beyond the tensioner and belt.

 

[2001LC]

Well...at least you solved the question of whether or not the 2UZ-FE is an interference engine or not. Good to hear there was no ancillary damage beyond the tensioner and belt.

Boyyyy...I've always been told this is an interference engine.

Has anyone ever heard of damage after TB break, under load?

 

[spressomon]

^ its been debated with most leaning towards the interference side. However when I did my first t-belt I gently rotated one cam by hand through its cycle and I didn't get any interference...FWTW.

I doubt if the crank, in jgray's t-belt break, stopped instantly...but just a guess.