glazed points - picture please

brianpharmd

brianpharmd

Senior Member
Does anyone have some pictures of glazed points? I am trying to troubleshoot an electrical problem. I tried searching for a thread on here but come across threads on glazed brakes more than anything. Google search has been unsuccessful. Apparently images of glazed donuts is equiv. to glazed distributor points. Who knew? :p

I need to know what I am looking for with glazing so I can rule it in/out as a possible cause.

Thanks
 
I think the word you need is oxidized not glazed. What is the problem you
are trying to fix?

Bob
 
.. a small file usually cleans up the points, unless they are worn down or pitted badly
 
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run a point file between the points and all glaze questions are removed from your dilemma.
 
Here is what is going on with my coupe. Part of an email I have been having with a member in the club who regularly posts on FB:

Now to the 30. Even less power at times, stepping on the gas with the car in gear caused the car to die. Having to use the hand throttle to give the car gas with it in neutral until it finally backfired and then it would go. Tried pulling out the choke when it was not running well but that just caused the car to die - either in gear or in neutral. Same thing with turning the GAV from fully seated to 1 full turn open - no improvement.
When checking spark at the coil wire to a head stud with moving the points, no spark or very erratic. If I isolated the points (business card between the points) and used a screwdriver to act as the points, good spark at the lower plate - so no points issue. Removed condenser from circuit and still had weak to no spark. Checked coil and only had 6.6 ohms at the terminals to coil wire (with red and black wires removed). Which was below spec. Changed to a new coil and now have good spark at coil wire/moving points and coil wire/using starter. Went for a drive and still running into the same issues with the car nearly dying. Car runs fine and then absolutely no power. Have to take it out of gear and pull down on the hand throttle to keep the motor running until it finally backfires and then engine rpms pick up. Then can put the car in gear and drive. I tried pulling choke and no help. Also tried turning the GAV from 1/4 open to 1 full turn open and no help. Turned on and off lights and no change."
Here are the suggestions from the club member - I have not had a chance to perform these checks yet this evening:
"If you have the original lower plate check the wire going from the points from the lower plate. They get broken strands from the wire moving, if you have modern lower plate check for bad contact at the foot that rubs on the upper plate.If that does not do it check for bad connects at the junction block. Could also be a bad switch. also check the points and make sure they are not glazed."
I had already run a points file between the points, that was why I was asking from a picture of glazed points. I guess I could pull the points out and look them over/take a picture if that helps.
Thanks,
Brian
 
Brianpharmd, I had simular problem last fall with Dad's 28. The points were opening and closing, but they were skipping a beat because the points would stay open (sticking open)
This wasn't discovered til I was dead on the road. I checked points gap to find them finally stuck in the open position.
Another possibility may be the distributor body. Use an ohm meter to insure you don't have an internal short. This has happened twice on this same car. Good Luck. Jeff
 
Are you sure the timing is in order? Also, check the upper plate to be sure that the points lug is secure in it's position. I had an upper plate with the fiber worn around the points lug which would cause the points to wobble giving erratic results.
 
A trick I learned from an old timer in my younger days was always run a piece of paper between the points after filing them. In the old days a paper matchbook cover was used. Today a piece of paper of that approximate thickness is in my tool kit.
 
I have checked the point gap = 0.02. Rechecked the gap again after running the car and having the same issues. Still at 0.02. I had replaced the condenser with a known good one (from my other Model A) and still have the same issue.

When I was checking for blue spark with the coil wire to the head nut and pushing the starter, I could see the points open and close (and spark) each time it went over a dizzy cam lobe.

I have modern upper and lower dizzy plates but my lower plate has the wire that connects the 2 plates, not the metal foot.

I have not had the chance yet to check either the upper/lower and ignition. I will recheck the timing but the last time I checked it, it was correct. Since the car has this lack of power intermittently - I tend to think that there is an intermittent electrical grounding issue more than a timing issue. Let me look at the above items along with Mitch's thread and a couple of PMs I recieved. Then I can reasses.

Thanks,

Brian
 
Just use an ohmmeter. Check for continuity with the points closed. High resistance means they are glazed. Or burnt.

Using a points file or even sandpaper is a quick fix when you're broken down or you plan on replacing the points anyway. When I was 16 years old making $1.25 an hour & a set of points cost $1, I filed points. I must have been good at it because I recall it was almost a weekly exercise. If you ever file a set of points, you will remove the metallic coating on them & reduce the life span considerably. Unless you plan to keep on filing them, plan on replacing them pretty soon! Usually burned points will have pits on one side & raised areas on the others. Sometimes they just wear unevenly. They will most always discolor as they have a coating on the surface. The usual causes of burned points are absence of cam/wearing block lubricant, condenser failure, a decreasing gap caused by wear on the rubbing block, mis-alignment, sanding w/ a point file, excessive current, setting an incorrect gap, leaving the ignition key on w/ the points closed, use of incorrect cam lubricant & poor quality metal. I've heard of points being welded shut, but I've never seen it happen.

The trick to points lasting a long, long time is (at least) annual maintenance. No matter how well it's running, check the gap & put a dab of points lube on the cam. Not bearing grease or Vaseline; use the correct lube.

Correct points installation & gap is also important. Make sure the blade is at a perfect right angle to the points & you want to feel just the slightest bit of drag when you pull the blade through the points. Make sure the blade is clean & that you dress the new points by running some card stock or a piece of brown paper bag through them. Check the gap on all four lobes of the cam. Make sure the points align correctly. Proper alignment is also critical to longevity. Look at the points when they are closed; both sides should mate evenly.

You can change points everyday & it will not fix bad bushings. If you are having trouble w/ points failure, check the shaft. If you detect movement, chances are it needs new bushings.
 
Here is an update of what I did last evening - I did not perform a spark test last night as there were thunderstorms so I could not move the car out of the garage:

I started at the battery and have been working my way to the dizzy. The battery tested fine. Checked water level and added a bit. Cleaned the terminals and got to bare metal again where the ground strap bolts to the car. Added some dielectric grease as well.
Pulled the dash. The red wire to the ignition was loose. Not out of the screw but loose that I could move it around on the screw. Also, ignition switch did not seem right either. Very loose and sounded "clunky" when turning the key inside the unit. Not like it normally acts. I ordered a new switch and a shorter ignition armored cable from Brattons. I had the long ignition armored cable and that was always a pain trying to keep it from hitting one of the ignition screws. It will arrive Thursday.​
Checked all of the terminal box connections and they are tight. None of the wires on the left post are close to the wires on the right post. I do have a grommet that goes over the ignition armored cable through the terminal box.​
Checked the fuse and one of the posts was slightly loose where it mounts to the plate portion of the fuse. Tightened everything up after cleaning and adding dielectric grease ​
Pulled the dizzy. Had to pry it out since it was frozen to the block with rust. Sanded the lower section of the dizzy to bare metal and the top of the head where it mounts. Will add dielectric grease there as well when I put it back in. The pigtail wire was fine. There is a grove in the insulation on the pigtail where it meets the upper plate but it is not all the way through. I took the dizzy apart. Lower plate was tight in the base as was the points/condenser on the upper plate. I took pictures of my points to get an opinion on whether they are normal or need replaced.​
I plan to put everything back together tonight with the new ignition switch/shorter armored cable. The I will run through the electrical diagnostic test and spark test.​
 

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BruceVA said:
Just use an ohmmeter. Check for continuity with the points closed. High resistance means they are glazed. Or burnt.

Using a points file or even sandpaper is a quick fix when you're broken down or you plan on replacing the points anyway. When I was 16 years old making $1.25 an hour & a set of points cost $1, I filed points. I must have been good at it because I recall it was almost a weekly exercise. If you ever file a set of points, you will remove the metallic coating on them & reduce the life span considerably. Unless you plan to keep on filing them, plan on replacing them pretty soon! Usually burned points will have pits on one side & raised areas on the others. Sometimes they just wear unevenly. They will most always discolor as they have a coating on the surface. The usual causes of burned points are absence of cam/wearing block lubricant, condenser failure, a decreasing gap caused by wear on the rubbing block, mis-alignment, sanding w/ a point file, excessive current, setting an incorrect gap, leaving the ignition key on w/ the points closed, use of incorrect cam lubricant & poor quality metal. I've heard of points being welded shut, but I've never seen it happen.

The trick to points lasting a long, long time is (at least) annual maintenance. No matter how well it's running, check the gap & put a dab of points lube on the cam. Not bearing grease or Vaseline; use the correct lube.

Correct points installation & gap is also important. Make sure the blade is at a perfect right angle to the points & you want to feel just the slightest bit of drag when you pull the blade through the points. Make sure the blade is clean & that you dress the new points by running some card stock or a piece of brown paper bag through them. Check the gap on all four lobes of the cam. Make sure the points align correctly. Proper alignment is also critical to longevity. Look at the points when they are closed; both sides should mate evenly.

You can change points everyday & it will not fix bad bushings. If you are having trouble w/ points failure, check the shaft. If you detect movement, chances are it needs new bushings.
Click to expand...

Bruce - I had checked the point gap at all 4 lobes and it is either 0.019 or 0.020. I believe that the points mate evenly with each lobe. There is no play in the dizzy shaft so I believe that bushings are fine. I included pictures in my previous post of the points to get an opinion of their quality.

Thanks,

Brian
 
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