Uh-oh! Snapped timing belt. - page 1 - Troubleshooting - VWDiesel.net The IDI, TDI, and mTDI source.

• Uh-oh! Snapped timing belt. by DCC on 14 Feb, 2008 02:53
• So, I was driving the other day home after a difficult day, and suddenly the engine stopped. I thought it might be the cut-off valve, so I called the insurance and they sent a tow truck and brought it to a well known mechanic, friend of mine.
  
  There we checked the cut-off valve and saw no fuel was going into the inyectors, we stared like "what the hell?", and then we took the timing belt cover apart and saw the damage.   :shock:
  
  Ok, I'm trying to get the car towed to the place where we (some vw freaks) meet to do our mechanical stuff. On saturday I'll try to get it fixed, here's the point:
  
  The engine cranks well, and seems like it doesn't hit the valves. My first idea is to take the valve cover off and see how the valves stopped. If the valves are closed, I'll put a new timing belt and see if that does the trick.
  
  The other option is obvious, unbolt the head, and take it apart to change the bent valves (I have 2 or 3 engines for spares).
  
  Any more sugestions?
  
  
  
  Sad moments..
• #1 by burn_your_money on 14 Feb, 2008 04:25
• Take the valve cover off and rotate the cam, if everything is moving properly you may have gotten lucky. Time it up and see if it runs, nothing to lose except some time in the event that a few valves are trashed.
• #2 by jimfoo on 14 Feb, 2008 05:57
• If it cranks well with no belt, I don't see how valves CAN'T be bent. I also don't know why you would crank it over with the starter, (which is what you make it sound like), with no belt on. Just slap a good 1.6 head on it and go.
• #3 by Vincent Waldon on 14 Feb, 2008 08:28
• If you are cranking it over with the cam installed and no timing belt the only real explanation for no noise is that the valves are already bent out of the way.  As far as I know there's no position on the cam where all 8 valves are simultaneously closed.
  
  'Course, I've been wrong before... ;-)
• #4 by DCC on 14 Feb, 2008 12:46
• Ok then, I'll try to tow it tomorrow, so I can open it up on saturday.
  
  "I'll show you how deep the rabbit hole goes"  :lol:
• #5 by rabbitman on 16 Feb, 2008 00:22
• I bet your cam is broke and your valves are bent, :cry: hope not though. I guess by now you know the problem anyways. If the head isn't trashed you could get new valves which aren't terribly spendy and if you need a cam I've seen new hydro cams on ebay for $50. Good luck
• #6 by smutts on 16 Feb, 2008 13:10
• Sounds like lots of bad news I'm afraid.
• #7 by hipifreq on 16 Feb, 2008 22:00
• Oh man, sorry to hear about the snapped timing belt. I had the same thing happen to my '80 Dasher a few weeks ago.
  
  The valves didn't bend at all. The #1 cylinder valves were both open, and they got pushed hard enough to snap the camshaft into four pieces.
  http://www.vwdiesel.net/phpBB/viewtopic.php?t=12393
  Made of MESS of the head. Big gouges in the aluminum. Totally scrap metal now.
  
  Hope your engine made it through. Any luck getting into it today?
• #8 by DCC on 17 Feb, 2008 09:26
• CARNAGE!
  
  Ok, so first odd thing I saw was the lower timing belt cover:
  
  
  Then saw that something was really wrong with this pulley:
  
  
  
  My guess is that the (insert nasty word here) who used the car before me had a terrible hobby: destroying everything he touched. I never saw a car that was treated so badly (mechanicaly). The keyway was non existant and the pulley was loose. That started wearing out the timing belt till it made a hole in the cover and bailed out. I had to unbolt the front mount and let the engine lean forward to take the whole shaft out.
  
  
  Old vs new:
  
  
  And the terrible truth: camshaft broken in three pieces.
  
  
  I didn't have time for more. The head is loose, but couldn't take it out, as I ran out of time. Next week I'll disarm every piece on it and see how it looks. Probably it will be a mess, so I will fit another head that lies somewhere in our warehouse. It is a pity, as that head was running perfectly.
  
  So you were all wrong, no bent valves at all. Just a destroyed camshaft.  :wink:
  
  
  DCC
  Taking blows the fun way.
• #9 by jimfoo on 17 Feb, 2008 10:57
• Quote from: "DCC"

  CARNAGE!
  
  So you were all wrong, no bent valves at all. Just a destroyed camshaft.  :wink:

  
  You forgot the keyword, YET. Wait until you pull the head. Sorry to hear about all the carnage though.
• #10 by zukgod1 on 17 Feb, 2008 15:13
• Get that head pulled and show us the bent (or not) valves..
  
  I'll bet there are a few, sorry but thats the way it goes I think...
• #11 by DCC on 18 Feb, 2008 01:10
• Quote from: "zukgod1"

  I'll bet there are a few, sorry but thats the way it goes I think...

  
  
  No need to bet, I KNOW there are a few, if not all. The camshaft was broken, and I saw some scoring in a couple tappets. I will disassemble the head asap and replace all the valves if the head is still usable.  
   :?
• #12 by hipifreq on 19 Feb, 2008 17:03
• OUCH!  :shock:
  
  If you plan on reusing the head be COMPLETELY sure that the camshaft seats and cam followers were not damaged when the camshaft broke. My own head was turned into scrap when broken camshaft gouged big chunks out of the bearing surfaces and a cam follower broke. All I'll get for it is $0.43/lb if I can get all the steel out of it.
• #13 by DCC on 24 Feb, 2008 03:35
• Ok, here's an update.
  
  Yesterday I lifted up the head and worked on it. Surprisingly, the head was perfect, not damaged. I can't say the same thing about all the valvetrain related stuff, though.
  
  The head is still in pretty good shape (the engine has some +100000 miles on it), usual cracks between valves, no signs of overheating and almost no carbon buildups. The valve guides were almost new, probably replaced not so long ago by the previous owner (yes, the useless mechanic).
  
  I took all the inner stuff out:
  
  
  
  Useless junk:
  
  
  
  BentValves 'r' us:
  (I will make a keyring out of one of those)
  
  
  Dissasembling the donor head (front). My head, behind, waits for its new set of valves, tappets and camshaft. I also replaced all the valve (seals? gaskets?).
  
  
  
  The engine block looks ok too. A friend of mine took a close look and told me that it should run well for a very long time (he had 2 1.6 gtd and owns now a 1.9TDI powered mk2 and a 1.8T powered mk1)
  
  
  
  So now I have a working head. Will make some cleaning and then bolt it up and get my car back to action. So far, not so bad.  
• #14 by jtanguay on 24 Feb, 2008 09:51
• you might want to flush your coolant though, unless its supposed to be brown?