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General Information => Troubleshooting => Topic started by: AdAm84 on December 14, 2006, 02:57:17 pm

Title: Timing belt off by a tooth?
Post by: AdAm84 on December 14, 2006, 02:57:17 pm

What would be the consequences of the timing belt being off by one tooth on the crank sprocket? I just replaced my timing belt and it will not start or stay running. You have to almost hold it to the floor to get it to start firing and then it will shut off when you let off. I locked the cam and pump when it was at TDC. Could the crank have moved enough to get one tooth off? or would it even run if it was? By the way its a 1.6 n/a rabbit.

Title: Timing belt off by a tooth?
Post by: burn_your_money on December 14, 2006, 03:17:21 pm

It's possible that the fuel is being injected too late, possibly past TDC so there isn't enough compression/heat to ignite the fuel. Just line everything up and check, it only takes like 10 minutes

Title: Timing belt off by a tooth?
Post by: Doug on December 14, 2006, 07:01:19 pm

If it was running okay before you chamged the belt then definitely you do not have the timing set right. Check the procedure in your manual. And do not run the motor until you have it corrected.

Title: Timing belt off by a tooth?
Post by: LeeG on December 14, 2006, 08:19:38 pm

did you have the cam sproket loose so it would rotate on the cam?

Title: Timing belt off by a tooth?
Post by: jtanguay on December 15, 2006, 05:53:12 am

yeah get engine at tdc, lock the camshaft and pump, then loosen camshaft pulley.  install belt, and 'tension' it with the tensioner.  once you have the right tension then you can tighten the camshaft pulley.  the belt will tension a little bit more once the pulley is fully torqued.  you might want to check pump timing just to be sure while everything is apart.

turn engine a couple of times and line everything back up... just to make sure there is no problems.  with all that being done, the motor should run fine.

Title: Timing belt off by a tooth?
Post by: AdAm84 on December 15, 2006, 11:16:39 am

Thanks for the help. it turns out the crank turned just the slightest bit. The cam and pump were locked so they weren't off. I turned it over until the cam and pump were at their appropriate locking positions and then checked the markings on the flywheel. The pointer was at the -10 mark. I think it might have moved a little bit when we tensioned it. We set it at the 0 mark and it runs smoother than ever.