Nurex Timing Gage

If talking about the Nurex timing wrench have used it multiple times. Just line up the timing pin in teh A in teh dimple, fully retard the advance lever, remove dist. cap and rotor, put the wrench onto the cam , loosen the cam screw, clockwise line the wrench handle up with spark plug 4 contact on top of teh dist. bod, tighten down the cam screw A little more to it, but that is the basics
 
Jim,
That's the setup I have. Question is when I set everything up and engine running with light on I see the mark on the crank pulley is exactly lined up with 0 degrees at idle and then 40 degrees+ advanced when I moved the spark advance arm to full advanced. I then shut down engine and installed plastic ring along with cam wrench which shows 6 degrees. So now what do I do? What does that 6 degrees tell me?

Instructions say 5 - 10 degrees retarded at idle when arm is fully retarded and should be 35 - 40 degrees at full advanced.
 
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Cape Codder said:
Jim,
That's the setup I have. Question is when I set everything up and engine running with light on I see the mark on the crank pulley is exactly lined up with 0 degrees at idle and then 40 degrees+ advanced when I moved the spark advance arm to full advanced. I then shut down engine and installed plastic ring along with cam wrench which shows 6 degrees. So now what do I do?

Instructions say 5 - 10 degrees retarded at idle when arm is fully retarded and should be 35 - 40 degrees at full advanced.
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I will admit that I am not 100% certain exactly what you are doing.

When you say "engine running with light on" I assume you mean you are using a timing light and some form of timing indicator down on the timing cover, by the crank pulley. If so, at idle with the spark lever fully up, yes, you should be at zero degrees advance (top dead center, or TDC) with the timing light on the timing indicator. Pulling the spark lever down all the way gives you 40 degrees of crankshaft advance. This all sounds correct.

And seriously, you can stop right here. The engine is timed correctly, as Ford called for.

If you insist on looking at the white disc up on the distributor, you can. Use the hand crank and the timing pin so that you are at TDC again. This step is important -- use the mark on the crank pulley and the timing indicator to confirm TDC. Install the white plastic disc and see where the rotor points to on the disc. You must take all of the slack out of the distributor shaft with the cam wrench by gently turning the cam clockwise. Then I use a pencil to mark a line on the top of the brass rotor tab at exactly the zero line on the white disc.

Now if you want to change the timing a few degrees, you loosen the timing cam screw, move this pencil line forward or back to make the change, and tighten the screw. Use the cam wrench again to take up all the slack to see where the new timing is (pencil line points to it on the white disc) and adjust if needed.

Everyone has their own ideas about where to set the initial timing. Ford said to set it at TDC. He also said to advance the timing lever about 1/2 way for most driving and a bit more at higher speed. Remember, over 30 or 35 MPH was "higher speed" in the Model A era. It is on this basis that I suggest that you go about 3/4ths of the way down for most driving we do today (except climbing a steep grade, where the engine will knock if you don't back off the timing a few clicks). If you are only putting around your neighborhood at 30 MPH or less, advance it 1/2 way.

Some guys like to set the initial timing 5 degrees AFTER TDC with the spark lever fully up, so that when you fully advance the spark lever, you get 35 degrees of advance while driving. Or you can set it initially to 10 degrees after TDC, in which case full advance with the lever is 30 degrees before TDC. I think that is what the instructions are referring to. I don't do that, but you can if you want to.

The spark lever gives you 40 degrees of timing change when it moves from the top of the quadrant to the bottom; so you can set it initially to some degrees after TDC if you want, and get less total advance before TDC with the lever all the way down. It is easy enough for me to just set it at TDC initially and move the spark lever down about 3/4ths of the way and drive on.

I hope this helps. Sorry this is so long. Feel free to call or email me if you want to discuss.
 
Just to e-emphasize post #8, all you're doing with that fancy tool (or Ford's original method) is setting the base, or initial, timing so the engine doesn't kick back while cranking and break the starter drive (or your arm!). The actual timing while running is totally controlled by that lever on the left side of the steering column.
 
Cape Codder, my first question is: Are your absolutely sure that the engine is at TDC when your timing marks are aligned? How did you determine TDC when you set up the NuRex timing gauge?
 
I followed the suggestion of a local engine re-builder who I feel is quite clever. He has in the past worked on many different engines and is always extremely busy.

His suggestion was to lay a flat bar on top of #1 cylinder ( I had the head off for replacement of valves) and then bring the piston to the bottom of the bar. Next, I marked the timing cover and crank pulley with chalk. I then turned the crank shaft counter clockwise and made another mark on the crank pulley lined up with the previous mark on the timing cover. I measured the distance between the two marks and divided that in half where I made another mark between the two on the crank pulley. That is Top Dead Center.
 
Cape Codder said:
I followed the suggestion of a local engine re-builder who I feel is quite clever. He has in the past worked on many different engines and is always extremely busy.

His suggestion was to lay a flat bar on top of #1 cylinder ( I had the head off for replacement of valves) and then bring the piston to the bottom of the bar. Next, I marked the timing cover and crank pulley with chalk. I then turned the crank shaft counter clockwise and made another mark on the crank pulley lined up with the previous mark on the timing cover. I measured the distance between the two marks and divided that in half where I made another mark between the two on the crank pulley. That is Top Dead Center.
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I have used that method myself. The timing pin dropping into the dimple in the timing gear, through the front timing cover, should confirm it.
 
katy said:
How far counter-clockwise did you turn it?
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Until it hits the bar over the cylinder (piston stop). This only works if the piston rises above the block at top dead center. If the pistons are flush with the block, drill a 3/8" or so hole in the bar and put in a bolt with head down and bring the piston up against the bolt in both directions.
 
Cape Codder, your method for finding TDC is exacting the way I would have done it and it is extremely accurate.
 
40 Deluxe said:
Until it hits the bar over the cylinder (piston stop). This only works if the piston rises above the block at top dead center. If the pistons are flush with the block, drill a 3/8" or so hole in the bar and put in a bolt with head down and bring the piston up against the bolt in both directions.
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Thanks
 
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