Finding TDC after broken timing belt is replaced

Hi:
After much cursing of engineers that think we have 17 elbows per arm, I'm ready to install a new timing belt on my 88 escort wagon. I replaced the
water pump (original cause of the problem, I suspect, it is in pretty sad shape - thanks to the engineer that decided this engine should be free wheeling!). Now all I have to do is find TDC and align the crank and cam shafts. The cam shaft is sitting nicely at TDC for cylinder 1 compression stroke as verified by the timing mark on the pully and the position of the distributor rotor. I'm a bit confused about the crank position - I can get it so the timing mark on the pulley points to the timing mark on the case, but I wanted to check something with you all here before proceeding. Since the crank makes 2 revolutions for each revolution of the cam shaft, is there a difference as to which of the 2 revolutions I match to the cam shaft? I'm thinking that it doesn't matter since the crank shaft is the same on each revolution. Please let me know if I'm wrong :)
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Glad you have extra elbows, you'll need them if you don't have a friend to help. TDC indicates you'll have compression in cylinder one. The crank will always be pushing the cylinder up when the mark is aligned, but the cam could have the exhaust valve opened for exhausting the cylinder, rather then having both closed. Remove the #1 plug, stick your finger in the hole, turn the engine over by hand. If you don't get air pressure, the cam is not aligned properly.
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<snip OP>

Well, I didn't really have the extra elbows to begin with, however, my bones have taken such a beating that my arms now resemble tentacles. Pretty sure I have the cam in the right alignment, as the distributor rotor is pointing at the number one position and there does appear to be pressure as indicated by your method. Now if only I could figure out how to get the belt to go on without getting out of alignment (as detailed in my response to Bob).
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Wrap the belt as tight as possible, opposite the side where the tensioner is, use a couple of spring clamps on each sprocket to keep it in place, then release and tighten the tensioner.
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You're on the right track. I usually line up the marks, install the belt, tensioner etc. and turn the engine over twice before rechecking the marks. If everything looks good put it all back together and away you go. Bob

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Sometimes it helps to slightly misalign the marks to start with so they line up correctly when your done. Try turning the cam clockwise until the mark is maybe 1/2 a tooth off. Install the belt and tensioner, turn the cam back and you should see the slack come out of the front of the belt as the marks get back in line. Bob
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<snip>

so I'll adjust accordingly.
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2/1 crank/cam the mark will be off on the next round but it will come back in line the next....
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Remember, INTAKE COMPRESSION COMBUSTION EXHAUST.
THE MARKS WILL BE OFF ON THE EXHAUST STROKE BECAUSE THE EXHAUST VALVE IS OPEN. JOHN sorry, left the caps lock on. J

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remove #1 plug. put finger in hole. turn crank till compresion pushes finger out of hole. align marks. put plug back in. put on belt. set timing. happy motoring
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wrote:

Fact: You're correct, the camshaft makes only one revolution, for each two revolutions of the crankshaft. Deduction: The camshaft will only make one half a revolution for every revolution of the crankshaft. Therefore, you can line up the crankshaft (while driving the camshaft sprocket via the belt) twice at it's timing mark, but only one time will the camshaft sprocket line up with its mark. Conclusion: Line up both the camshaft sprocket with its mark and the crankshaft sprocket with its mark, and the valve timing will be set as the factory intended it. As for your remarks about the engineers, the Escort was a basic car, sold at a comparatively cheap price. While it might make servicing a nightmare, it's cheaper to build a drivetrain for a FWD (like a Ford Escort has) vehicle and simply drop the body onto it during assembly. It was built in a very economical assembly process, Ford could produce thousands of them a day, and good thing, they pretty much sold like hotcakes. The assemblers don't really give much of a hoot that after many miles past warranty, someone's going to have to replace the timing belt or water pump. You wish they would, but they don't answer to you, they answer to the guys that say, "how much is it going to cost us to build it, and can we build it cheaper than that?" You end up with a "nightmare" when it comes to servicing it on the passenger side, but Ford's got their money out of it, they really don't care that it's difficult or unconventional to someone else service it.
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the mark is there. Line up the marks and install the belt. It does make it easier to unload the cam.
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You worked out how to find tdc , to align the cam have both lobes on NO1 just rocking neither will be under spring load , sounds odd but look and you will see , then slip the belt on , make some marks with white out if you doubt your ability to hold thing still , this should match the std timing marks its works on every OHC motor Ive worked on over the last few years and is even better if you have a degree wheel.
Zaphod Beeblebrox wrote:

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