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View Full Version : WTF....Timing chain broke?



hernandez3011
08-22-2009, 02:07 PM
[headbang] On my way to work yesterday morning, I was cruising at 65MPH, all of a sudden the car stops accelerating. I look down and I am at 0 RPM. The first thing I assume is, my timing belt just snapped (strange considering it was replaced at the stealership only 4 months)

I pulled over, cranked the engine and all I hear is the starter turning over. No engine. I open the hood remove/pull the timing belt cover only to see it is intact. I pressed on the bottom of it and it is tight and good. Needless to say, AAA towed the car to the dealership and Melton VW is going to look at it for free since they replaced the belt themselves.

I have searched for cam chain and timing chain and I am only getting info on the cam chain tentioner (which I also replaced 1.5 months ago). With that said, the question is....has anyone ever heard of broken cam chain/timing chain? Any links or personal experience? The dealership is going to look at it Monday since I brought the car late.

Broncoman75
08-22-2009, 02:55 PM
a broke timing chain would make the engine die, but wouldnt keep it from being able to turn the crankshaft over...

99blueb5
08-22-2009, 04:17 PM
but it could have kept spinning a belt the valves, and everything is bound up

ExZion
08-22-2009, 07:09 PM
My money is on sheered off teeth on the timing belt. My 1.8t did the same thing. From the top timing cover everything appeared all well and good (belt on and taunt) but at the crankshaft a section 8-10 inches long was missing all its teeth. When Cranked with the starter all you could hear was the starter do to the fact there wasn't any compression.

Mawhitey
08-23-2009, 03:36 AM
I would say the bottom pulley has sheared its keyway and allowed the timing to go out and valves touch. Probably due to the pully not having been tightened correctly or checked when the belt was changed. I had it, caused me to scratch my head for a bit as the belt was still intact and tight, and the visable marks were still in line. It wasn't until i removed the head i noticed that TDC wasnt TDC

Good luck with it

ghost6303
08-23-2009, 08:33 AM
[headbang] On my way to work yesterday morning, I was cruising at 65MPH, all of a sudden the car stops accelerating. I look down and I am at 0 RPM. The first thing I assume is, my timing belt just snapped
ok, a reasonable thing to do. however if you think your timing belt snapped, why would then you do this...

I pulled over, cranked the engine and all I hear is the starter turning over. No engine.
and thow any possibility of you not destroying your head when the belt snapped down the toilet by trying to crank the engine more?

hernandez3011
08-24-2009, 12:55 PM
ok, a reasonable thing to do. however if you think your timing belt snapped, why would then you do this...

and thow any possibility of you not destroying your head when the belt snapped down the toilet by trying to crank the engine more?


If the timing belt is snapped the engine isn't going to turn over thus the valves aren't going to move anymore. The damage is already done. The reason I cranked the engine is because About a year ago my car did the same
Thing and I thought it was the timid belt. I pulled over and the car started started right back up. I checked it for codes only to find out it was a crank position sensor. It was really random but the car has run fine ever since.

Anyway, I got a call from the stealership. Apparantly the cam chain tesnioner broke. Falied. Whatever. I bought the part from S&G 4-5 month ago. My buddy is going to donate a cylinder head to me and I am going to build it with supertech valve springs and arp head bolts. The stealership quoted the head replacement a 13.5 hour job. I'm gonna do it myself. I am
Mechanically inclined, do most work myself in my garage or driveway. Turbo, FMIC (custom designed by me :-) LOL) exhaust, high flow mani. Etc
Anybody have any tips of what to watch out for, be careful with, tricks. Thanks fellas

urban96
08-24-2009, 03:25 PM
take your time, label all the bolts and buy a can or 2 of PB blaster

ghost6303
08-24-2009, 07:19 PM
If the timing belt is snapped the engine isn't going to turn over thus the valves aren't going to move anymore. The damage is already done.

that is not correct. if the belt breaks, the head & cams will not move. the pistons still will. the starter will still spin the crank. every once in a while when someones timing belt breaks, they get (extremely) lucky and it doesnt do any damage to the head, or maybe only one or two valves bent. but any chance of being that lucky is destroyed when you try to crank it over after the belt breaks. you almost always will end up doing more damage.