Point gap

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RandyB

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My manual says .17 for the point gap on my 273 that sound right? It’s still not firing
 
Sounds good to me. I think we ran 16-18. So 17 sounds good. I would wipe the contacts with alcohol or a cleaner that does not leave a film. We also use to run a finger nail file thru the contacts to remove any film on them.
Make sure you have a good condenser or you will never have spark.
 
My manual says .17 for the point gap on my 273 that sound right? It’s still not firing

No it doesn't. It says .017. .17 is .170. That said, if you use a dwell meter, it'll be much more accurate.
 
I knew what you meant.
In an emergency you can use a matchbook cover to set the gap on your points. A lot of people don't carry a dwell tach around in their back pocket or a dwell meter either.
 
I knew what you meant.
In an emergency you can use a matchbook cover to set the gap on your points. A lot of people don't carry a dwell tach around in their back pocket or a dwell meter either.
So I’m gonna gap it at a flat part of the cam to .17 correct?
 
Up on the peak.

Put the zero in after the. To make Rusty Happy or else leave the. Off. .017 or 17
 
Up on the peak.

Put the zero in after the. To make Rusty Happy or else leave the. Off. .017 or 17

It wasn't about me bein happy. It was about makin sure he was using the correct measurement.

And everyone who runs points should have and know how to use a dwell meter. They are much more accurate.
 
If you were to set the gap on the flat part then the points would be open all the time.
You set the gap on the peak of the lobe to 17.
 
By the way the closer the points are together the higher the engine Revs. That's why we used 16 quite a bit.
Now here's some more info for you. You will notice that the spring for the point has a slotted opening where you hook the wires up that go to the coil and you hook your condenser to. Now if you push the spring in to where it shortens the points spring that gives you more tension on your points which also allows you to rev higher.
The negative side of having more tension on your point is that you will wear them out quicker and have to replace them sooner.
 
By the way the closer the points are together the higher the engine Revs. That's why we used 16 quite a bit.
Now here's some more info for you. You will notice that the spring for the point has a slotted opening where you hook the wires up that go to the coil and you hook your condenser to. Now if you push the spring in to where it shortens the points spring that gives you more tension on your points which also allows you to rev higher.
The negative side of having more tension on your point is that you will wear them out quicker and have to replace them sooner.
Thinking of just going hei
 
My manual says .17 for the point gap on my 273 that sound right? It’s still not firing

Lubricate the contact arm and cam lobe with a touch of synthetic disc brake grease, unless you can find some point cam lube, which is very difficult to find these days, or your point arm contact pad will wear out if short order.

Also, since it is Halloween, you can take an old condenser, charge it up using one of your spark plug wires and leave it laying around for someone to pick up.

Reminds me of the time I picked up a magneto with all the plug wires hanging on it from an early Hemi powered boat. An obnoxious acquaintance thought the plug ends looked cool, so he reached down and grabbed them. I gave the magneto a good spin, and he nearly shat himself. Trick or treat.
 
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Every boy (and girl) that touches an engine of any kind should know how to gap points and make them work, and WHAT makes them work.

I hardly ever use a feeler. When I used to set points, I just "eyeballed" them and then set them with a dwell meter. You can set dwell "on the starter."

Look at which way the shaft rotates. Clean the cam of any dried or excessive grease and put a tiny dab of lube on the "approach" side of the points rubbing block, so that the shaft rotation moves the grease "into" the rubbing block

Make sure you have a good condenser. If you replace the old one, keep it for a spare. "New parts" are not always "good."

As said above set the gap on the HIGH point of the cam. If you have a stick car, you can put the car in "high" gear and "bump" the car back and forth on the suspension to bump the engine "that last bit" to get the cam on the "high" point of the lobe
 
It will run at just about any gap, as long as the points actually close and actually open.
The specified gap is for new points in a new distributor, and is used to ballpark the dwell. The dwell is the thing that your coil is looking for.
Dwell is the time in degrees that the points are closed, causing a charge to build up inside the coil. When the points open, the coil fires it into the coilwire, to be distributed . The more dwell a system can generate the better, but there is a point that more is not necessarily useful. The coil works best, over a broad range of rpms, at the specified dwell, created by the specified pointgap.
That don't mean that it won't work at any other point gap.......
 
That don't mean that it won't work at any other point gap.......

That's very true, but that DOES mean that from say a .060" gap to a .015" gap there will be a huge timing difference, since point gap directly affects ignition timing, which is why it's best to "get it right".
 
I knew what you meant.
In an emergency you can use a matchbook cover to set the gap on your points. A lot of people don't carry a dwell tach around in their back pocket or a dwell meter either.


Who carries match books around any more??? :rolleyes:
 
So I’m gonna gap it at a flat part of the cam to .17 correct?

points have to be exactly on the highest part of the points cam. Clean up the ‘ cam’ set the points then put alittle lube on the cam. If you set the point gap on the flat part , it will never work
 
Did that Sir and still no fire.

did it run before you changed the points ?
I did see one time a set of points that were bad out of the box ( shorted to ground).
Start at the basics
Power going to the points
If you crank the motor with a test light on the wire coming out of the points ( to the coil) it should flash. if it doesn’t , it’s the points . If it does , it’s something else
 
did it run before you changed the points ?
I did see one time a set of points that were bad out of the box ( shorted to ground).
Start at the basics
Power going to the points
If you crank the motor with a test light on the wire coming out of the points ( to the coil) it should flash. if it doesn’t , it’s the points . If it does , it’s something else
It did run before I got my damn hands on it. I put a D4B manifold on it and a 4 barrel Edelbrock carb on it. Replaced the stock manifold and stock carb with them. Took the transmission out to get rebuilt and took the distributor out because the engine might of tipped back causing the distributor to hit the firewall
 
No spark ?
Ok
Start systematically at the beginning and work your way thru the ignition system. It’s not that bad. If you jump around it will drive ya nuts
Start at the ballast resistor on the firewall and work forward from there
You have 12 volts TO the Dist ?
( could be a connection that got missed)
With a test light check power at the coil while cranking.
 
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