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Discussion Starter #1
Oh noooo!! Shes seized!!
2003 2.5 ACV

No idea what went wrong but it seems fairly serious

I plan to whip off the head next week and see if I can see whats damaged
Basically I've been having a recurring problem with my pump belt front tensioner breaking - the metal actually snaps off.
This was the 4th time fixing it, this time I fitted a new crank shaft pulley to see if that fixed the problem
We timed her back up, turned the key and bang bang bang bang bang (the bad type of knocking bang that we all dread)
she never went again - wont turn a single budgie

I'm hoping its just top end damage but even if it is, I still need to get to the root of the problem
Any idea what might cause the tensioner to break more than once?? Other symptoms were a very jumpy scattery timing chart when we had the computer plugged in
Damper pulley? Dual mass fly wheel?

and what might allow the engine to fire up if the timing is so far out? (I'm guessing the knocking and resultant seizing means that the timing was way out?)
Faulty 5th injector not communicating with the ECU?

Thanks in advance if you can offer any help or advice!

I'm not sure if its worth rebuilding if I can't get to the root of this - if it happened again I'm not sure I'd be able to retain my composure!
Time for a 1.9 coversion?
Its a 2.5 ACV 2003

Cheers

Dave
 

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2.5 with the timing FAR out....that's valves hitting pistons...NOT just a head job. :eek:
What belt/tensioners were you fitting? (Genuine or cheapo?)
Confused that you say "pump" and then "crank shaft pulley"...different ends of the engine!
Injectors have b*gger all with the "mechanical" timing of the engine....
What you've had (by the sound of it) is a major MAIN belt out of alignment... and then the valves have a fight with the pistons.
Sometimes just ONE valve bends, and 1 piston has dents in it....other time...all 5 are fooked (I bought a 2.5TDi 'velle with exactly that problem....5 bent valves, and 2 pistons with HOLES in them!)

NOTHING to do with the pump belt....even if that was not fitted, you couldn't do the sort of damage you now have.
Scrap engine at a guess.....I bought a perfectly good 2003 'velle (see above) for 500 quid simply 'cos they hadn't changed the main belt/tensioners/water pump/etc..belt slipped due to missing/worn teeth...and it needed a new engine....more than the van was worth in Norway!
 

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I too bought my van years ago for a song due to a messed up timing belt however i ave decided to whip the ead off to check for damage and rebuild properly ! I found very faint marks on pistons- sign the timing was off by a smidge but the valves were straight as a die- they are thick stem 8mm on the ACV...ported the engine, added a hybrid LT turbocharger and a set of AUDI c4 AEL inectors and the van been fine ever since. I have used the previous timing belt kit as it was just freshly fitted however last year i had to change belt and tensioner as nearly destructed ! I believe there was a faulty batch of timing belt tensioners as i've done it properly 1st time too !

I suggest you take rocker cover off and assess damage, if cam is in 1 piece then you're lucky however i had instances when valve broke and dropped inside piston which i suspect its the problem in your case too ! Either way take cyl ead off and assess damage before ordering a new engine, if head is good and pistons not damaged then you might proceed fixing it. Get pd150 headbolts cut to size (darkside developments sell them on their site or make your own !), add pd black tappets and get stronger valve springs too- i got inner valve springs and talers from vw for AFN 110 Bhp engine, they were about 30 quid a few years ago ! Throw in an Elring head gasket kit and youre onto a winner...
 

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Discussion Starter #4
Rocker cover came off today along with the crank belt cover .. so the belts are all fine, the cam shaft is is one piece and there's 1 lifter looking damaged.. it looks as though the top of the lifter has sheared off

Going to get the head off soon for a more thorough assessment but how the heck can the timing be out if the belt is all good!?

If the flywheel was on its way out could this have been responsible for the scattered timing and the breaking of the tensioners? If said flywheel finally died could this have sent the timing out causing the engine to seize?

OrGAZm; they were not genuine belts / tensioners when fitted 4 years ago but not cheapo either...
I mentioned the damper pulley coz my mate reckons that's what may have caused timing scatter and break all those tensioners
 

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The belt can jump a few teeth. Normally this happened if an auxiliary belt breaks and wraps itself around the bottom pulley. I had this happen on a V70 D5 it jumped 5 teeth and the belt looked like the day it was put on.
 
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