checking timing

midgetracer said:
I use a phillips screwdriver instead of the pin because the screwdriver has a sharper point and it is easier to feel the dimple.
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I would do the same if I felt a need for a point. I don't like to modify good original parts.


When the pin drops into the dimple, the rotor should be in this position. Exactly this position, and not in the middle.
 

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Tom Wesenberg said:
I would do the same if I felt a need for a point. I don't like to modify good original parts.


When the pin drops into the dimple, the rotor should be in this position. Exactly this position, and not in the middle.
Click to expand...


As I had mentioned before, my rotor tip is bent down slightly below the pin. I'll adjust the rotor position as you state but is it too low below the pin? Do I need to try to bend it up? Will that mess up the gap?:confused:
 
Tom, I had to re-set the timing pin and it went in no problem, but my rotor in showing in the opposite position as yours on the #1 pin on the distributor housing. Do I need to loosen the cam and position the rotor like yours? And there is some slight backlash on the rotor which the book says is acceptable, but how do I compensate for that? The cam/rotor spin counter clock wise so i assume I need to tighten the cam screw after adjusting the rotor for backlash so the rotor is exactly what looks like just past sparking? Also, when positioned on the #1 are points fully opened or in your picture past spark and fully closed or past the high point on the cam lobe? I've gaped the points at the recommended gap.
 
bigd1101 said:
Tom, I had to re-set the timing pin and it went in no problem, but my rotor in showing in the opposite position as yours on the #1 pin on the distributor housing. Do I need to loosen the cam and position the rotor like yours? And there is some slight backlash on the rotor which the book says is acceptable, but how do I compensate for that? The cam/rotor spin counter clock wise so i assume I need to tighten the cam screw after adjusting the rotor for backlash so the rotor is exactly what looks like just past sparking? Also, when positioned on the #1 are points fully opened or in your picture past spark and fully closed or past the high point on the cam lobe? I've gaped the points at the recommended gap.
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The picture is taken where the radiator is to the right of the picture, and the firewall is to the left of the pictures, and as you are standing on the passenger side of the motor bay.


Perhaps you are viewing the distributer from the Drivers side of the motor bay?


With the timing pin in the dimple, the rotor should be pointing to the #1 cylinder, # 1 cylinder is closest to the water pump and radiator.
 
Not mentioned so far is using the Nu-Rex timing wrench, only about $8 or so. The wrench adjusts the points for lash/backlash, and does not require a meter/lamp to set points. It is a good thing to understand what this old school method teaches you about the theory of your A's ignition, helps you trouble shoot when things are not working properly. The wrench is a quick and easy way to set your points. Especially valuable if you need to check set points when you are on the road.


Do a search on the Barn for the wrench, info available.
 
What you have done is to locate the crank and camshaft to be in the position where the spark will occur and the engine will run at idle. The spark timing lever should be in the up ( retard) position. Now the points should just be at the point where the points are at the place where even the slightest movement will break (open). The point gap would be the widest point opening so it must be set before any of the above is done. The rubbing block on the moveable point would be sitting on the highest part of the dist. cam. So, set gap,locate crank, retard spark lever, With loose screw - locate the rotor where it just has reached the #1 lug, then tighten the screw. now with the ignition on wiggle the rotor CW. CCW. and there should be spark at that moment.
 
As mentioned, but, in order
Find TDC with pin.

Lever up

Set point gap to .020" [ at highest position on cam lobe]

Turn point cam lobe to remove slop/slack [ technical term] and tighten at position where points just start to open with rotor pointing to lower right [ right fender as in Tom's pic]. Test light can also be used for this.

You can bend rotor end to achieve desired rotor to cap pin clearance. [ .020-.030"]. They bend hard and rotor can be easily broken if not careful.

Timing can also be checked as in my previous post by moving timing lever when finished.

Timing is right when engine starts and idles slowly with the typical Model A sound with lever fully up. Idle will smooth up and speed up with lever 1/2-2/3 down in normal operating position and with lever fully down the idle should start to roll and roughen slightly.

Its what everyone has said, just in order.
 
You can raise the rotor higher by putting small cardboard pieces on top of the distributor shaft. This is easier than trying to bend the stiff brass. I don't recall seeing this problem.
 
Update: I followed these instructions on this link below and I did this test as instructed with the results stated....yay! And I think I have it set to specs gap wise.



http://www.abarnyard.com/workshop/timing.htm



The final check is to simply turn on the ignition switch. Using the screwdriver at the cam screw, turn it clockwise as if tightening the screw. The SLIGHTEST movement of the screwdriver and cam in the opposite (counter clockwise) direction should clearly spark the points. If the points won't spark the setting is too tight and too advanced and the points aren't closing. If there is any noticeable movement of the cam before the spark then the setting is too far retarded. Don't forget to turn off the ignition. Leaving it on with the points closed may result in a dead battery or burned out coil!
 
Got a Nu Rex wrench coming.......watched the video. I was worried about the lash/backlash and looks like the Nu Wrench will do the trick! Thanks folks, as always!


Don
 
Not mentioned so far is using the Nu-Rex timing wrench, The wrench is a quick and easy way to set your points.
Click to expand...

Never used one, eyeballs always worked for me.
 
Y-Blockhead said:
Have your wife (or girlfriend hold the secondary wire while you slowly rotate the engine. If she jumps at the same time you feel the detent in the cam gear, you are good to go.

Just hope you get it right the first time... :p:p

Seriously, I use a "Buzz Box". The Buzz Box is the same principal as the light, buzzes when the points open. Only difference is the Buzz Box supplies it's own power so you can use it while an engine is on a stand or if you have a Mag.

I bent up a couple of these 1⅜" wrenches to fit the ratchet nut to slowly turn over the engine. Just don't start the engine with it on the nut!! :eek::eek:

44255122664_39bfe29d09_z.jpg


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Any advantaged to using the wrench vs the crank?
 
100IH said:
What you have done is to locate the crank and camshaft to be in the position where the spark will occur and the engine will run at idle. The spark timing lever should be in the up ( retard) position. Now the points should just be at the point where the points are at the place where even the slightest movement will break (open). The point gap would be the widest point opening so it must be set before any of the above is done. The rubbing block on the moveable point would be sitting on the highest part of the dist. cam. So, set gap,locate crank, retard spark lever, With loose screw - locate the rotor where it just has reached the #1 lug, then tighten the screw. now with the ignition on wiggle the rotor CW. CCW. and there should be spark at that moment.
Click to expand...

So, after all this exacting effort to get the timing "exactly right", you start the engine and pull the spark lever down to where "that sounds about right"! Where is the timing at now? Don't know, do you!
 
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