Ignition timing

PostPost by: twincamman » Sun Nov 10, 2013 9:31 pm

Note. ......you have to reset the static timing before you replace the distributor remove the dist set the static timing then replace the dist with the rotor at 11 o'clock sorry I missed a one last time ....ed
dont close your eyes --you will miss the crash

Editor: On June 12, 2020, Edward Law, AKA TwinCamMan, passed away; his obituary can be read at https://www.friscolanti.com/obituary/edward-law. He will be missed.
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PostPost by: twincamman » Sun Nov 10, 2013 9:36 pm

Oops sorry I should have said 11oclock ......point the rotor at eleven o'clock .....ed
dont close your eyes --you will miss the crash

Editor: On June 12, 2020, Edward Law, AKA TwinCamMan, passed away; his obituary can be read at https://www.friscolanti.com/obituary/edward-law. He will be missed.
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PostPost by: billwill » Sun Nov 10, 2013 9:47 pm

twincamman wrote:I see the problem?....I assumed you had removed the valve cover and aligned the cam marks opposite when setting the crank pully ...........did you do this ???? If not go sit on the naughty step



I think what twincamman is trying to say is that because the main crankshaft turns twice as fast as the distributor jackshaft, there are TWO positions in which the front crankshaft pulley is pointing at the TDC (or 10 degree) timing mark and you may have selected the wrong one.

It has to be the one in which piston 1 is on its compression strole which is most easily found by taking out sparkplug one and putting you finger over the hole, while you rotate the cranksshaft pully with a spanner. You will feel the compressed air trying to lift your finger on the compression stroke.

Or you can do it as twincamman says by taking off the cam cover tand checking that the two cam sprocket marks are facing each other and not as wide apart as possible.

You can also check which stroke it is by opening the oil-filler cover and looking at the positions of the valves of cylinder 4. which is doing its exhaust stroke when piston 1 is doing its compression stroke.
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PostPost by: billwill » Sun Nov 10, 2013 9:54 pm

twincamman wrote:Note. ......you have to reset the static timing before you replace the distributor remove the dist set the static timing then replace the dist with the rotor at 11 o'clock sorry I missed a one last time ....ed



That sentence doesn't seem to make sense Ed.

Static timing means settind the distributor contacts to open at the right time.

Do you mean just: set the crankshaft at approx 10 degrees before TDC on the Cyl 1 compresstion stroke, before you put the distributor in?


....
The put it at 11 oclock rule assumes that the HT leads are inserted in the standard holes in the ditributor cap.
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PostPost by: twincamman » Sun Nov 10, 2013 10:32 pm

No set the cam and crank timing to zero then put the dist in place ..advance the crank pulley to 5 degrees spark the plug ....... then move the wires to the correct outlet on the cap ...if incorrect....This will start the motor then set the timing with a light?........I put tie wraps on the first 3wires to avoid mixing them up one on one two on two etc so the wires read 1234 at the plugs. But 1;342 at the dist
dont close your eyes --you will miss the crash

Editor: On June 12, 2020, Edward Law, AKA TwinCamMan, passed away; his obituary can be read at https://www.friscolanti.com/obituary/edward-law. He will be missed.
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PostPost by: billwill » Mon Nov 11, 2013 2:35 am

twincamman wrote:No set the cam and crank timing to zero then put the dist in place ..advance the crank pulley to 5 degrees spark the plug ....... then move the wires to the correct outlet on the cap ...if incorrect....This will start the motor then set the timing with a light?........I put tie wraps on the first 3wires to avoid mixing them up one on one two on two etc so the wires read 1234 at the plugs. But 1;342 at the dist



You are just going to confuse Uboat with that advice, I very much doubt that he will need to move the wires to different places on the distributor cap, but I don't have a correct diagram on hand at present.

Is there a diagram in the Workshop manual?
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PostPost by: twincamman » Mon Nov 11, 2013 4:34 am

Ok ..I'm out
dont close your eyes --you will miss the crash

Editor: On June 12, 2020, Edward Law, AKA TwinCamMan, passed away; his obituary can be read at https://www.friscolanti.com/obituary/edward-law. He will be missed.
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PostPost by: twincamman » Mon Nov 11, 2013 4:53 am

1. Crank pulley at 0 .........2cam marks facing in position 3 dist in withone clip adjacent to block-and rotor at 11oclock 4 spark plug if the wires are in the cap are right it should start at 5 degree advance .......good luck
dont close your eyes --you will miss the crash

Editor: On June 12, 2020, Edward Law, AKA TwinCamMan, passed away; his obituary can be read at https://www.friscolanti.com/obituary/edward-law. He will be missed.
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PostPost by: billwill » Mon Nov 11, 2013 7:52 pm

This photo shows the standard arrangement of plug leads in the distributor cap on a Twin-Cam engine.
The firing order is 1-3-4-2
LotusDistieLeadsTop_1024.jpg and
Standard Wiring of Distributor Cap.


You should check that your distributor cap is wired this way before doning anything else with your timing and as Ed says, mark the plug leads so that you know which lead goes on which sparkplug at any time in the future.


I didn't mark my number 2 lead when I replaced it, but as it is the only one with no markers there is no confusion.

8)
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PostPost by: Uboat » Sun Nov 17, 2013 3:38 pm

I have now adjusted the timing and I found out that there are sparks also on the second revolution/tdc where piston no 1 is on the lowest position. No need to take of carbs, but removing airbox back plate made everything very very easier.
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PostPost by: billwill » Mon Nov 18, 2013 1:41 am

All along we have been assuming that your car had a standard ignition system. But has it in fact been converted to a wasted-spark two coil system?

If so the second wasted-spark would not be when piston 1 was at the bottom, it would be at the top of the exhaust stroke,
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PostPost by: Uboat » Mon Nov 18, 2013 7:19 am

Sorry for the confusion, I have a Pertronix electric ignition...
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PostPost by: billwill » Mon Nov 18, 2013 2:01 pm

Uboat wrote:Sorry for the confusion, I have a Pertronix electric ignition...


But other than that pertronix, the distributor, and its cap and the coil are standard are they?

If so, you should not get sparks on Number 1 cylinder at any place other than top dead centre (+ advance)
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PostPost by: Uboat » Mon Nov 18, 2013 9:00 pm

I have original coil and distributor, with pertronix cap with leads in regular order.

Tried to start engine but lousy starter does not give me a fair chance
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PostPost by: billwill » Mon Nov 18, 2013 9:31 pm

I still can't understand why you are getting a spark in the wrong place.

I suggest you get a set of these spark testers so that you can see exactly what your sparks are doing as you tun over the engine .

http://www.ebay.co.uk/itm/LASER-TOOLS-2 ... 0452238857
Image

It somehow seems that you still have not got the distributor inserted correctly.
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