Anybody have this happen before. (timing belt buzzsawed thru beams timing cover)

[Celica RA45]

its hydraulic tensioner so no spring and it might of just shat itself

[2jzhilux]

this is more common than you would think
check your timing tensioner for side movement also check your water pump bearing
what happens is the water pump gear or tensioner pulley bearing will wear causing the timing belt to try to run off the pulleys and eat into the cover
have seen this on many 1hz timing belts too not same motor but same principle but it wears the belt away on the cover
i have pulled belts off that have been 20mm wide and still running on a 1hz and when they snap its not pretty

[urantia]

Makes alot of sense ecotechilux, but yes first time i've seen this happen. Good thing these toyota motors with belts can't destroy themselves when they do snap.

Thanx for clearing that up celicara45

[RT104GT]

You gotta loose bolt down here and if you dont fix it kiss goodbye to 24 valves$$$

[Moppitt]

Ive seen the exact same thing happen to a 5cyl volvo engine. Bent all the valves too. IIRC the belt was way past its replacement interval but im not sure if that was the root cause of the failure. Is that tentioner sitting crooked or is the belt loose on it there?

[joecoolmk2]

looks very strange how the belt is fully on the cam pulley's, yet it would have to come off a fair way to do that!

on my 1UZ, the water pump runs off the back of the timing belt, and the pulley has a little lip to track the belt.

i'd say it's the tensioner or idler pulley. that idler/tensioner pulley looks crooked in the photo, and that metal part on the block looks to be touching the belt. definately something wrong there.

[aw11man]

Hey all thanks for your thaughts and info,

I can tell you that the idler pulley wheel is not straight like u said joecoolmk2 and
that thing sitting on the belt moves with some attached assembly behind the idler
wheel is also not straight.

[takai]

Just to bring this up again, a friend of mine has had the timing belt eat through the cover on his 3S as well. Not sure of the final diagnosis.

[oldcorollas]

ask Mos about his tensioner....

one of the pulleys has to be wonky.. hopefully not the crank or the cam pullys

[aw11man]

Well mine ended up being a broken idler pulley bolt, just clean snaped for no aparent reason, after i had it repaired i discovered that the beams 3s engine is an interference type (valves can and did hit pistons), could barely start it and it sounded horible.

Always look through the ports after an event such as this BEFORE putting engine back in and you might see a dirty bent valve or 3 thus saving you a heap or horsearseing around.

Having said that i think the gen 1, 2 and maybe 3 are non interference but check anyway.

[5000gt]

ouchies for bent titanium valves.....

oh wait, you had a red top yeah.... no Ti for you!! haha jks