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Setting the points - in book and my way-similar


Lou Earle

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I learned how to set points on an A model Ford and this is a slight adaptation of that procedure that has worked very well for me on ALL point ignitions from 49 caddy to 34 Plymouth.

1- trace the #1 plug wire to see where it is on dist and make a WRITTEN note - like at 6 O'Clock or 2 O'Clock- the common places.

2- either remove the plugs or have a remote starter button attached to the solenoid so you can bump the starter to tdc.

3- Remove the dist cap- but not distributor -and then turn the motor by hand or by the starter button to where it sits on tdc at the pointer .Or whatever point is the set point( some are 3 degrees or so before or after).

The rotor button should be pointing at the #1 spark plug wire area- if not your one rotation of engine and 1/2 rotation of dist off - .

If your at the set point with he pointer on the dampener then note the location of the end of the rotor button.

4- remove the dist at this point and bench set the points to 20 or the proper setting- I don't believe anyone can really set points accurately in the car - Lord I have tried !!

5- re-install the distributor so the rotor is pointing to where it was when removed and not 180 off!! As I have often done!!

6-Now take your test light and attach a jumper wire with alligator clips at both ends to the point of the test light .

7 make sure-test- the test light on the battery to make sure there is current flowing from the alligator clip on the point to the test light

8 So now you have 2 alligator clips on test light one original and one you added to the point via jumper wire- attach one to the side of the distributor(ground) and one to the moving point side of the points - hot-.and

turn on ignition .

9 -rotate the dist until light is off. Then rotate - slowly- until light turns on then back to off and very slowly back to on- just when light turns on is the place.

Lock her down and fire her up.

When the light comes on-that is the point where the spark jumps the points and causes ignition.

Hope this helps

Lou

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I always set points with the distributor in place. I make an initial set at the spec. I hook up a dwell meter and crank the engine over to get a dwell reading. Then if needed I make an adjustment until I achieve the specified dwell. This gives an exact point setting that you can't get with a feeler gauge.

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Dwell can be determined with the meter attached, dist. cap off and points just snug so you can vary the gap while spinning the starter...the dwell will accurately be displayed on the meter. However I am sure some of you remember engines starting back in the hey day of the hi-po engine..tune up a hi-po 383 while engine is hot and that sucker will start and run while setting the dwell..cap or no cap..little diesel effect there...

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I always use a dwell meter to set points and then adjust the static timing to the correct value.

Because I always had cars that were as old as I was, I adjusted final timing on a road test.

What is correct dwell for one of these flathead 6s? About 40 degrees?

Rule of thumb I learned was about 2/3 of each cylinder ignition stroke swept angle should be dwell in order to generate adequate spark. The 4 bangers that i cut my teeth (and many other things....knuckles, fingers etc :) ) on usualy ran 58-62 degrees.

Tim

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For my 1933 with its Delco-Remy distributor, the points are to be set at a gap of 0.020 inches or 36 degrees of dwell.

For your "new" 1940s cars with their AutoLite ignition systems the values might be different. However since I see 0.020 gaps mentioned for your cars too the dwell might also be the same.

It should be in my 1946-53 Plymouth service manual but I don't have that with me.

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AND . . . . . . if you set the dwell while cranking the engine and then discover that it has changed when it is running at idle, it's distributor bushing time. JMHO:D

I usually try to favor the low side of the dwell spec range, cause when things wear at all the dwell will always tend to go up as the points begin to wear in the more closed direction. I've had a small tube of rubbing block lube in my tool box for the past 30 years, and it's still almost full - the stuff lasts forever, and you only need a scotch - but you need it fer shurr . . .

On the subject of setting timing, I have found one vibration damper-type crankshaft pulley with the outer ring almost 30 degrees away from TDC, so watch out for this if you haven't had things apart lately. I've also discovered that all the truck engines I've ever seen (218) use a one-piece stamped steel crank pulley. May not idle quite as smooth, but it'll never walk away from the TDC mark, either. JMHO

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Dwell can be determined with the meter attached, dist. cap off and points just snug so you can vary the gap while spinning the starter...the dwell will accurately be displayed on the meter. However I am sure some of you remember engines starting back in the hey day of the hi-po engine..tune up a hi-po 383 while engine is hot and that sucker will start and run while setting the dwell..cap or no cap..little diesel effect there...

Tim;

Pull the plugs to eliminate this.

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My book says .020 inch for 1946 thru 54. Says dwell of 34 1/2 to 38 degrees for 46 thru 52, and 39 degrees +- 3 degrees for 53-54.

The higher the dwell degrees, the lower the point gap.

Norm is correct per my book too. Point gap .020" and dwell 36-38 degrees. I have converted my Desoto flathead 6 to dual points but the way I adjusted the dwell on the bench will work for single points too. As I did not have a distributor machine I used an electric drill and a 6 volt power supply to set the dwell on the bench. I locked my drill trigger switch in the on position with the distributor shank chucked up. The drill I used runs at 550 RPM's and this is equal to 1100 engine RPM's as the distributor spins at half of the engine speed. I started with the base setting for point gap and then adjusted the dwell by re-adjusting the point gap with the distributor spinning while observing the dwell meter.

As I have mentioned many times before the advantage of using dual points allows a closer point setting and increased dwell time for better coil saturation time and a hotter spark. With the dual point setup the point gap base setting is .017". The final dwell is 46-48 degrees. The dual point backing plate has anchor pins that are slightly offset. One set of points opens first and before they close the second set of points opens thus allowing a longer dwell time. At the reduced point gap there is less arching and point life is extended. Should one set of points fail while on the road I can simply remove the wire from the failed set and use the second set to continue after I adjust the ignition timing.

drill2.jpg

dual_points_1.jpg

DualPts3.jpg

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You guys know your stuff. Great tips. For anyone just learning tune up work, this would be a good thread to print and save.

I learned tune-up while working in a service station in Southern CA in the 60's. When I moved back to Fla, I hired on at a Standard Oil station and the owner would introduce me to his regulars as his "new tune up man, just came in from California." Pressure!:D

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Neat Idea, Don C! I like that redneck distributor machine idea - best I've seen in a while. The sorry reality here is that I'll bet there are a blue million old Sun distributor machines gathering dust that no one can figger out what to do with - wish I had about two. They were great, for unlike Don's bench drill trick, these machines could spot a bent shaft from the flashsing strobe lights at each degree position for the cam lobes - wonderful way to set advance curves and check out centrifigul and vacuum advances, too!

Anybody know where one can be bought?:rolleyes:

Thanks

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