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Follow-up to Replaced Head Gaskets; engine won't start

After weeks of searching through posts on this site and elsewhere and not finding the answer to my problem, I used my own logic to finally resolve the issue. I had spark, fuel and compression and my DOHC 2.5L would not start. It did crank, but would not start. I kept feeling like it was a timing issue, but everything I read said if all of the timing marks are all lined-up, it can't be miss-timed. After trying numerous other avenues i.e., using TDC on crankshaft by mistake, fuses, electrical components, fouled plugs, weak ignitor, bad wires, low fuel pressure, broken crank gear tab, bad crank position sensor, bad cam position sensor, bad wiring, loose ground, plugged exhaust, bent valves, bad neutral safety switch, bad ignition switch etc..., I kept coming back to the timing issue in my gut. I don't have a 3D model to work with to see the position of each piston in relation to each cam and the sensors, but it seemed to me that it DID matter where the #1 piston was in relation to everything else. It also made sense to me that if the cam pulleys lined up to the marks correctly and if I just rotated the crankshaft 180 degrees and lined-up those marks, I would effectively move the #1 position back into synchronization with the camshafts. Well, it worked!
I will let the "experts" say it isn't so and try to tell me the engine can't be out of time if all of the timing marks are lined-up either way, but I know what worked for me.
No thoughts on this? I'm having the same problem with my 99OB 2.5 DOHC after a rebuild. Hey Paur4s, what mark did you use on the crank sprocket when you turned it 180. I guess the crank keyway was then at the 12 O'clock position when the cam gears lined up with their marks?
 

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the belt install position for the crankshaft puts the pistons at their half-travel point. There is only one tab at the rear of the crank sprocket with a dash/line/groove on it and assuming all other positive factors (no slipped keyway? no broken tab?) if that tab is positioned near 12 o'clock and aligned with the groove on the CPS mounting 'boss', and the cams are aligned properly, you install the belt. Release the tensioner, turn the crank sprocket around 2 times back to the install mark, and the cams should be at their own marks. The belt markings will be lost (and may not line-up again for over 100 revolutions) but a good triple check before starting the car is a tooth count between all the sprocket marks.

If the alignment tab were at 6 o'clock, the pistons would also be at half travel and likely no valve-to-piston contact could occur, but, there would likely be no/little compression and no chance of starting the engine.
 

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the belt install position for the crankshaft puts the pistons at their half-travel point. There is only one tab at the rear of the crank sprocket with a dash/line/groove on it and assuming all other positive factors (no slipped keyway? no broken tab?) if that tab is positioned near 12 o'clock and aligned with the groove on the CPS mounting 'boss', and the cams are aligned properly, you install the belt. Release the tensioner, turn the crank sprocket around 2 times back to the install mark, and the cams should be at their own marks. The belt markings will be lost (and may not line-up again for over 100 revolutions) but a good triple check before starting the car is a tooth count between all the sprocket marks.

If the alignment tab were at 6 o'clock, the pistons would also be at half travel and likely no valve-to-piston contact could occur, but, there would likely be no/little compression and no chance of starting the engine.
I understand and agree with everything you've sated Texan. I'm having the same issues as paur4 with my 99OB and was hoping for clarification on his solution. It sounds like he set the cam marks with the crank 180 off the mark ( keyway at 12o'clock position ) and then his engine started. Which makes no sense, but somehow he fixed his problem.
 
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