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Distributor No 1 Rotor Arm Position

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Can someone help, i need to know which posthole is for the no. 1 ht lead on my car. The car in question is a 1985 Esprit S3.

I have been a C*&k and messed them up, is there anyone out there who can help me or, if i can find them, do i need to hire the A team?

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This might not help mate, but on the 907 engine, No 1 is at 6 o'clock.

Generally though, if you pop off the dizzy cap and crank the engine over to TDC, the rotor arm should be pointing at No 1. Does this help?


Or be pointing 180 degrees away from no1.

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To take it one step further. The number one plug wire has to be plugged into the port where the rotor is pointing when the engine is at Top Dead Center.

The reason why I mention this is that I had to re-route the plug wires when I did my C-Service. Because the last time a mechanic worked on my car... he used the TDC -plug the wire in technique. But according to the service manual the rotor should be pointing at about 10 O'Clock from the rear of the car with the engine at TDC and that port should have the #1 plug wire plugged into it. After you run all the wires and start the car you will have to rotate the distributor to set the timing (this will throw off the 10 O'Clock reference). Good luck

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Guest Troy Halliday

If nothing has been disturbued then follow the suggestions on here and rotate the engine to TDC and then you'll see which one its pointing to (or very close to). If your timing was correct before you removed the leads it will be ok after so no need to reset timing.

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Distributors rotate at half crankshaft speed...thus, at TDC, your rotor arm will either be pointing at no.1 cylinder, or 180 deg out. You need to make sure that no.1 cylinder is on the firing stroke..this is best done by aligning the timing marks on the camshafts, the little dots on the rear face of the cam pulleys. When these two are pointing at each other, you have TDC on the firing stroke for no.1 cylinder, and the rotor arm will be pointing at No1 plug lead. As Troy says, if you haven't disturbed the distributor and your timing was OK before, it should still be fine. It doesn't matter a toss to the engine which of the 4 positions is no.1, as long as the no.1 lead goes to it and all the others follow in sequence in firing order, taking into consideration the direction of rotation. This only matters when you have removed all the leads from the cap and want to replace them...if you do it "by the book" it might not necessarily be correct; once had a 2 litre Alfa which had the distributor installed 180 deg out and wouldn't start,with the leads as per manual, as a consequence..going back to first principles 1 at TDC on the firing stroke soon sorted things out.

Scientists investigate that which already is; Engineers create that which has never been." - Albert Einstein

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acording to the service notes the rotor guset should be pointing to about 7 o'clock so the rotor arm points to 1 o'clock that beeing at tdc and the cam dots fasing each other and the ignition sproket having the dot pointing to the crank.

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