Problem with Zero TDC Flywheel. Help Please!!

[viseven]

Hello all.
I knew this forum some time ago as I have a Volvo 745 D24T with +710.000km's and run very well, but now i have a problem.

A few days ago i started my car and the engine feel unstable, smoky black, got worse until the engine stalled.
The pulley of injection pump is skidded (surprisingly, not have cotter pin in the keyway) and the motor is stopped by this problem.
When I put the pump back to her point, I checked the distribution timing was correct, and saw that it was not correct.

My d24t has two marks on the flywheel, a line and a zero ( http://i49.tinypic.com/19pefo.jpg ) . I removed the first injector and used a very thin steel wire to feel the T.D.C., which coincided WITH THE LINE on the flywheel.
However, in the Greenbook there is no mention of this line, and makes reference of the zero "0" as T.D.C., which is a few degrees AFTER T.D.C. Any body out there who could tell me which mark to pay attention to? I'm worried of mistiming the camshaft and ending up scrapping the motor.


Thank you very much for your attention and dedication.

Jorge.

[745 TurboGreasel]

Mine is timed to a line, and I haven't seen a '0'.(it's manual trans)

[viseven]

Hi, thanks for response. My engine have 2 marks on the flywheel and the gearbox is manual M46+OD.

[v8volvo]

Mine have always had a "0" in the correct location, but it can be hard to see.

Did your cam timing belt slip too, or just the rear pump belt? If the front belt is still intact, you can use the cam to help you figure out where TDC is, assuming it was timed more or less correctly last time someone put a belt on it.

I've never seen one where the 0 was incorrect. There is only one way to put the flywheel on, so it would be hard for it to be wrong. If it were me, I would try timing it both ways (to the 0 and then to the line), and spin the motor over by hand with a wrench and see which position makes the valves and pistons collide. Either way if you are unsure you will want to give the motor plenty of rotations by hand before you ever try spinning it with the starter -- you don't want to risk busting up the valves!

Make sure you're able to see everything clearly on the flywheel -- sometimes dust and corrosion can obscure the markings. Sometimes I stick a wire brush down in the hole and then spin the crank so that the surface gets cleaned up a bit, and then you can additionally use a paint pen on the marking locations to make them clearer.

[ian2000t]

I think on mine I have a "0" - I think with a dash either side - so "-0-".

I have to be honest I never actually checked this was TDC accurately - I just followed the greenbook and assumed it was. Mine runs well, and no valve smash after cambelt swap so it must be TDC or close to it. I don't get the MPG I would expect though, and always consider playing around with the injection timing a bit to see if I can find sweeter spot.

Although if "0" isn't very accurately TDC, cam timing would also be out on mine. What are the symptoms of having cam timing too advanced/retarded on these engines?