Tensioner pulley broked...could my valves be bent??

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nismo831
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Car: 300zx (z32)

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One of the tensioner pulleys broked and messed up the timing, the timebelt didnt snap, does anybody kno if this couldve bent my valves???


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t.mcginley.jr
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There's one tensioner pulley and 2 idler pulleys... which one broke? And did it actually break off or just get loose?

If the belt slipped at all or became loose then you probably have bent valves. If somehow the belt didn't slip/become loose then it's possible you don't have bent valves

nismo831
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Car: 300zx (z32)

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It is the tensioner pulley, it completely came off, made a hole on the belt cover, car imediately turned off and the timing is way off :frown: engine was bearly put in and now im pretty sure im screwed, sucksss

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t.mcginley.jr
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Ouch! :frown:

The timing is way off because once the timing belts come off or gets messed up, the cams and crank are free to rotate separately. Did you already take the timing cover off to see what it looks like in there?

If the belt is like hanging off, at the very least your valves will be bent. The only way to check the damage is to take the heads off to see what the valves and pistons looks like. If it's only the valves you will be lucky. When this kind of thing happens, pistons can break or crack, valves get jacked up, the heads themselves can crack, etc.

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t.mcginley.jr
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Btw if the heads are messed up, they sell used rebuildable heads on ebay for like $100 each, like this one:

http://www.ebay.com/itm/1993-93-94-95-9 ... _500wt_665

nismo831
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Car: 300zx (z32)

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The belt didnt come off it stayed in place

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t.mcginley.jr
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So the belt stayed in place but lost tension? If it lost tension thats probably how the timing got messed up. The only way to really check valves/pistons is to pull the heads off. You haven't tried starting it since then have you?

nismo831
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No not yet i am going to change da belt n fix the timing, also check the compression n c if it turns on

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t.mcginley.jr
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Good ideas. If the compression its good then you should have to worry about broken/cracked pistons. Then you just have to worry about the valves being bent

J30tChumpCar
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If the compression is good in all cyls there is no damage to worry about.

I am sure someone will not like this but you could skip the compression test and go for turning the key after you are 100% sure the new belt is timed properly, if it fires and runs proper it has compression and no damage, if it runs rough then check compression.

What made you turn it off? noise? Rough running?

nismo831
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Car: 300zx (z32)

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I was driving the car n it shut off while running it didnt make any noise it just turned off..

J30tChumpCar
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Sorry it is likely hurt, you can still give a new belt a try, you aint going to hurt it worse attempting to start it.


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